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TRANSCRIPT
26th CRSI-National Symposium in Chemistry
CRSI-NSC-26
February 07-09, 2020
Abstract Book
Jointly Organized by
Department of Chemistry VIT Vellore, CRSI, & RSC, UK
Contents
Welcome
Organizing Committee
Message from Founder President, CRSI
Message from Founder Chancellor, VIT
Message from Pro Vice Chancellor, VIT
Message from President, CRSI
Message from Dean, School of Advance Science
Acknowledgements
Program
Abstracts
President’s Lecture
Animesh Chakravorty Endowment Lecture
CRSI Medal Lecture
C. N. R. Rao National Prize for Chemical Research
CRSI Honorary Fellowship Lecture
C. N. R. Rao Award Lecture
Silver Medal Lecture
Mizushima - Raman Lecture
Third Charusita Chakravarty Memorial Lecture
Lifetime Achievement Award Lecture
Bronze Medal Lectures
Invited Lectures
Abstracts Posters
1
Welcome Message from Organizers
On behalf of organizing committee of the 26th National Symposium in Chemistry (NSC) and 14
th Royal
Society of Chemistry Joint Symposium under the auspices of the Chemical Research Society of India
(CRSI), we are delighted to welcome you to the symposium and to the Vellore Institute of Technology
Vellore.
The 26th CRSI-NSC meeting is attended by a large number of scientists, academicians and students
from universities and academic/research institutions spread across the length and breadth of India.
The meeting is attended by nearly 200 registered participants. The symposium has 34 lectures that
include CRSI medal lectures, special lectures. More than 130 posters will be presented by faculty and
students.
The Royal Society of Chemistry, UK has been partnering with CRSI in organizing a one day
symposium, along with the CRSI National Symposium over the years. This year also, there will be a
CRSI-RSC symposium on February 6, 2020, preceding the CRSI National Symposium at Vellore.
The main purpose of the NSC meeting is to create a platform where scientists, teachers and students
across the country come together and discuss recent developments in the area of chemical sciences.
Meetings like this that encompass all the domains of chemistry can help to build long lasting
collaborative endeavours in the frontier areas of chemistry and its allied disciplines.
We thank the CRSI governing body and council members for their valuable inputs and continuous
encouragement. The credit of the success of this meeting shall go all the faculty members and
students of the Department of Chemistry, VIT Vellore. We acknowledge our gratitude to The
Chancellor, Vice-Presidents, Asst. Vice-President, Vice-Chancellor, Pro-VC, Registrar, and the Dean
of SAS for their support. We thank the sponsors for their financial aid and support. Last but not the
least, we thank all the participants who have travelled far to attend the symposium.
We wish you a great time at VIT Vellore during the symposium
Sincerely
R Vijayaraghavan, Kaushik Chanda and Priyankar Paira
(on behalf of the Organizing Team)
2
Organizing Committee Department of Chemistry, VIT Vellore
S. No. Committee Members
1 Dean Dr. A. Mary Saral
2 HoD Dr. S.L. Manju
3 Convener Dr. R. Vijayaraghavan
4 Organizing Secretaries Dr. Kaushik Chanda Dr. Priyankar Paira
5 Registration Dr. I.V. Asha Rani
6 Reception Dr. K. Thenmozhi
7 Transport Dr. K.K. Cheralathan
8 Printing Dr. A. Anand Prabu
9 Guest Care Dr. Madhvesh Pathak Dr. Tamas Panda
10 VIP Guest Care Dr. S. Sasikumar
11 Mementos/Banners/ Tags/Abstract Book/Pen Drive
Dr. Kaushik Chanda Dr. Anisha Thomas
12 Food Committee
Dr. Kannadasan i/c Dr. K.K. Cheralathan Dr. K.R. Ethiraj Dr. G. Thirumanavelan Dr. K. Thirumoorthy
13 Men's Hostel Dr. M. Shiva Shankar
14 Ladies Hostel Dr. Barnali Maiti
15 Cultural Dr. G. Madhumitha
16 Finance
Dr. R. Vijayaraghavan (i/c) Dr. Kaushik Chanda Dr. Priyankar Paira Dr. Mausumi Goswami
17 Accounts Dr. R. Vijayaraghavan
18 Poster Committee Dr. V. Vijayakumar i/c Dr. S. Rajasekar Reddy Dr. Sovan Roy
3
19 Poster Evaluation Dr. G. Buvaneswari Dr. V. Vijayakumar
20 Hall Arrangement Dr. Pundlik Rambhau Bhagat
21 Website Dr. R. Vijayaraghavan
22 Pre Conference Dr. U. Vijayalakshmi
23 Abstract Compilation/Segregation/ Data Extraction
Dr. Priyankar Paira
24 Formatting/Abstract Book Making/RSC&CRSI
Dr. Kaushik Chanda
25 Writing to all speakers/Council Members/RSC Delegates
Dr. R.Vijayaraghavan
4
Message from Professor C. N. R. Rao
Founder President of CRSI
5
6
Message from Dr G. Viswanathan
Founder Chancellor, VIT
7
8
Message from Dr S. Narayanan
Pro Vice Chancellor, VIT
9
10
11
Message from Professor N. Sathyamurthy
President of CRSI
12
Message from the President, Chemical Research Society of India (CRSI)
I am delighted that the Division of Chemical Sciences at the Vellore Institute of Technology
(VIT), Vellore has come forward to host the 26th
CRSI National Symposium in Chemistry
during February 7-9, 2020.
This is the first time that the CRSI National Symposium is hosted by a private university. We
are particularly pleased that VIT, an Institution of Eminence is hosting the event.
On behalf of CRSI and on my own, I would like to express our gratitude to Professor R
Vijayaraghavan and his colleagues for organizing the symposium consisting of several
bronze, silver, gold and other CRSI medal lectures and invited lectures by different awardees
and a special symposium on Materials. I could see that it is going to be an exciting event.
We are pleased that Chemistry – An Asian Journal has brought out a special issue to celebrate
20 years of CRSI, founded by Professor C N R Rao. It will be released at the Symposium and
it showcases the chemistry research in India. It is worth mentioning here that India is No. 3
(China (1), USA (2)) in terms of total number of publications in the world now.
The Royal Society of Chemistry, UK has been partnering with CRSI in organizing a one day
symposium, along with the CRSI National Symposium over the years. This year also, there
will be a CRSI-RSC symposium on February 6, 2020, preceding the CRSI National
Symposium at Vellore.
With an ever increasing life membership and an increasing participation by young research
scholars, each CRSI National Symposium reflects truly the state of chemistry in the country.
There is a number of prizes to be won by young chemists for their work presented in the form
of posters.
Looking forward to a fruitful meeting in VIT Vellore,
Yours sincerely,
N. Sathyamurthy
President, Chemical Research Society of India, Bengaluru
13
Message from Professor A. Mary Saral
Dean, SAS
14
15
16
Acknowledgements
17
26th CRSI National Symposium in Chemistry (NSC-26) Programme
Friday, 7 February 2020, Venue- Ambedkar Auditorium, Technology
Tower , Ground Floor , 9.30 to 18.05
08:30 - 09:30 Registration
SESSION I: INAUGURATION AND PRESIDENTIAL ADDRESS 09:30– 10:30
10:30 – 11:00 HIGH TEA
SESSION II: SPECIAL LECTURES CHAIRPERSON: V. Krishnan 11:00 – 11:45 Animesh Chakravorty Endowment Lecture
A. S. Borovik, University of California-Irvine, USA
Molecular Complexity and Inorganic Chemistry: Utilizing Non-Covalent
Interactions to Control Function
11:45 – 12:15 CRSI Medal Lecture Arun Yethiraj, University of Wisconsin-Madison, USA Polymers in ionic liquids
12:15 – 12:45 C. N. R. Rao National Prize for Chemical Research G. U. Kulkarni, JNCASR, Bangalore
Au Au decahedra: Unusual nucleus for unconventional lattices
12:45 – 16:00 LUNCH AND POSTER SESSION I, CS hall Posters No. 1 to 65 P132-139
14:00 – 15:00 COUNCIL MEETING (Members only), Board Room, MGR Block
15:30 – 16:00 TEA/COFFEE
SESSION III: MEDAL AND SPECIAL LECTURES CHAIRPERSON: S. Chandrasekaran
16:00 – 16:45 CRSI Honorary Fellowship Lecture Sunney I. Chan, Academia Sinica, Taiwan Taming Methane: A catalyst for Efficient and Selective Methane Oxidation under Ambient Conditions
16:45 – 17:05 Bronze Medal Lecture Ranjani Viswanatha, JNCASR, Bangalore Mn emission: Energy transfer or Charge transfer
17:05 – 17:25 Bronze Medal Lecture Manmohan Kapur, IISER, Bhopal Transition-metal-catalyzed Distal and Remote Functionalizations
17:25 – 17:45 Bronze Medal Lecture Rajakumar Balla, IIT Madras Measurement of absorption cross-sections and kinetics of radicals relevant
to the Earth’s atmosphere using Cavity Ring Down Spectroscopy
17:45 – 18:05 Bronze Medal Lecture S. G. Srivatsan, IISER, Pune Probing Mood (Structure) Swings of Non-Canonical Nucleic Acid Motifs
18
18:15 – 19:15 CULTURAL PROGRAM, Anna Auditorium
19:30 – 21:30 DINNER, Foodys
Saturday, 8 February 2020, Venue: Gallery -2, Tech, Tower, 2nd Floor
9.30 to 18.15
SESSION IV: SPECIAL/MEDAL LECTURES CHAIRPERSON: Sourav Pal 09:30 – 10:15
C. N. R. Rao Award Lecture Richard Catlow, University College London, UK Modeling, Synchroton Radiation and Neutron Scattering Studies of
Structure, Dynamics and Reactivity in Catalytic Systems
10:15 - 10:45 Silver Medal Lecture K. Vijayamohanan Pillai, IISER, Tirupati Phosphorene Quantum Dots: Electrochemical Preparation, Doping and Possible Applications
10:45 – 11:15 TEA/COFFEE
SESSION V: MEDAL LECTURES CHAIRPERSON: R. N. Mukherjee
11.15 – 12.00 Mizushima - Raman Lecture Tahei Tahara, Riken, Wako, Japan Time-Domain Raman Spectroscopy and Its Application to
Ultrafast Photochemical / Photobiological Reactions
12.00 – 12.30 CRSI Medal Lecture Jagadese J. Vittal, National University of Singapore, Singapore My Journey with Crystals under UV Light and beyond
12.30 – 13.00 Third Charusita Chakravarty Memorial Lecture Srabani Taraphder, IIT Kharagpur Reaction Coordinate, Free Energy and Kinetics in an Enzyme Catalysed Proton Transfer Reaction
13:00 – 16:00 LUNCH AND POSTER SESSION II Venue – Foodys Poster No. 66-131, P140
15:30 – 16:00 TEA/COFFEE
SESSION VI: MEDAL LECTURES CHAIRPERSON: K. P. Kaliappan 16:00– 16:30 Silver Medal Lecture
Subrata Ghosh, IACS, Kolkata
19
Natural Products Synthesis – Some Fascinating Aspects
16:30 – 16:50 Bronze Medal Lecture Mahesh Hariharan, IISER, Trivandrum Ultrafast Excited State Dynamics of Twisted Aromatics
16:50 – 17:10 Bronze Medal Lecture Ashwani Kumar Tiwari, IISER, Kolkata Effects of Mode-Mode Coupling on the Dissociation Dynamics of H2O and CH4 on Metal Surfaces
SESSION VII: LIFETIME ACHIEVEMENT AWARD LECTURE CHAIRPERSON: N. Sathyamurthy 17:10 – 18.00 T. Ramasami, CSIR-CLRI Chennai
A Story of an evolution of a chemist 18:00 – 19:15 General Body Meeting and Presentation of Medals/Awards
19:30 – 21:30 CONFERENCE DINNER, Foodys & Greeno
Sunday, 9 February 2020, Gallery -2,Tech, Tower, 2nd Floor, 9.30 to
13.15
SESSION VIII: MEDAL LECTURES CHAIRPERSON: G. Sekar 09:30 – 09:50 Bronze Medal Lecture
E. Balaraman, IISER, Tirupati Non-noble metal catalysis: Applications in dehydrogenation and related reactions
09:50 – 10:10 Bronze Medal Lecture Gouriprasanna Roy, IIT Tirupati
Biomimetic Studies to understand the mechanism of Hg−C bond
protonolysis by mercury-resistant Organomercurial Lyase MerB
10:10 – 10:30 Bronze Medal Lecture Santanu Kumar Pal, IISER, Mohali Highly Efficient Ambipolar Charge Transport in Semiconducting Discotic Liquid Crystals
10:30 – 11:00 TEA/COFFEE SESSION IX: THEMATIC MINI-SYMPOSIUM CHAIRPERSON: S. Muthusamy 11:00 – 11:30 Invited Lecture
R. Vijayaraghavan, VIT, Vellore Development of Sensors & Proto type set up for Fruit Ripening Application
11:30 – 11:50 Invited Lecture Hongdoo Kim, Adjunct Faculty, VIT, Vellore Hybrid Piezocapacitive / Piezoelectric Sensor Based on Electro spun
20
Nanowire Web
11:50 – 12:10 Invited Lecture A. Senthilkumar, VIT, Vellore Redox Active Organic Molecule Functionalized Carbon Nanomaterials for Elegant Electrochemical Immuno-sensing of Shrimp-Virus
12:10 – 12:25 Invited Lecture S. Senthilkumar, VIT, Vellore Rationally Designed Ionic Liquids for Electrochemical Sensing
12:25 – 12:40 Invited Lecture S. K. Ashok Kumar, VIT, Vellore New Thorium (IV) Selective Sensors
12:40 – 12:55 Invited Lecture S. Sarveswari, VIT, Vellore Organic Small Molecules as Chemosensors
12:55 – 13:15 Concluding Remarks
13:15 – 14:15 LUNCH AND DEPARTURE, Basket ball court, Opposite to Tech Tower
21
Abstracts
22
26th
CRSI National Symposium in Chemistry
President’s
Lecture
23
Narayanasami Sathyamurthy
Honoraray Professor Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore Jakur, Bemgaluru560064. E-mail: [email protected] Dr. N. Sathyamurthy received his Ph.D from Oklahoma State University, USA. After working as post
doctoral fellow with Professor J.C. Polanyi at the university of Toronto Canada, he joined IIT Kanpur
as lecturer in the department of Chemistry where he roles to the rank of an institute professor. He was
the former director of IISER Mohali. He has authored more than 200 research papers in national and
international journals. He has received several awards and recognition in the country.
24
President’s Lecture
Chemical Oscillations and Synchronous Pulsed Flowering in Passiflora incarnata N. Sathyamurthy*
Jawaharlal Nehru Centre for Advanced Scientific Research, Bengaluru.
In addition to the familiar Belousov-Zhabotinskii oscillatory chemical reactions, there are several
complex chemical reactions that exhibit spatial and temporal oscillations. Our recent discovery of
―synchronous pulsed flowering‖ in passion flower suggests underlying activating and inhibiting factors
that are responsible for temporal oscillations in flowering as well as spatial patterns in a flower.
Spectrochemical investigations of the anthocyanins in passion flower bring forth the challenges
involved in studying natural products chemistry.
Illustration of synchronous pulsed flowering in Passiflora incarnata in the year 2017.
References:
1 Goyal, S.; Reji, R.; Tripathi, S. S.; Sathyamurthy, N. Current Science, 2019, 117, 1211-1216.
25
26th
CRSI National Symposium in Chemistry
Animesh Chakravorty Endowment
Lecture
26
A.S. Borovik Professor Department of Chemistry University of California Irvine, California 92697 USA Email: [email protected]
A. S. Borovik was raised in Chicago and received his B.S. degree in Chemistry with Honors from
Humboldt State University. As an undergraduate student he did research at Oregon State University
as an NSF Summer Fellow and at Woods Hole Oceanographic Institution as a WHOI Fellow. Both
research experiences involved using nuclear chemistry to trace metal ions in the environment. He
obtained his Ph.D. in Chemistry at the University of North Carolina-Chapel Hill under Tom Sorrell
where he developed photophysical models for the active site of copper proteins. As an NIH
postdoctoral fellow with Larry Que at the University of Minnesota, he designed synthetic complexes
that replicated the properties of dinuclear iron centers in proteins. Upon completion of his postdoctoral
fellowship, Professor Borovik joined the faculty at Ithaca College where he taught chemistry and
mentored 6 undergraduate research students for two years. He then moved to the University of
California-Berkeley as a postdoctoral associate with Ken Raymond, working on stereonostic
coordination chemistry. From there, he joined the Chemistry Department at Kansas State University
where he began a broad program on the effects of the secondary coordination sphere on metal ions.
After 3 years, he moved his research group to the University of Kansas, continuing research on the
development of metal complexes and hybrid materials with unique structural and functional
properties. In 2006, Professor Borovik and his research group moved to the University of California-
Irvine, expanding his approach to now include designing artificial metalloproteins. Professor Borovik
has won several teaching and research awards that include a 2017 MERIT Award from the NIH and
the 2018 National Cotton Award in Synthetic Inorganic Chemistry from the American Chemical
Society.
27
Animesh Chakravorty Endowment Lecture
Molecular Complexity and Inorganic Chemistry: Utilizing Non-Covalent Interactions to Control
Function
A.S. Borovik* Department of Chemistry University of California Irvine, California 92697 USA
Location matters…no compound operates in isolation without interacting with its local
environment. Metalloproteins are example systems whose active sites contain intricate
structures that aid the performance of specific functions with high selectivities and efficiencies.
The complexity of these systems complicates the study of their function and the understanding
of the properties that give rise to their reactivity. One approach that has contributed to the
current level of knowledge is the study of synthetic constructs that mimic one or more aspects of
the native metalloproteins. These systems allow for analysis of individual components of
structure and how they affect function. We are thus able to establish structure-function
correlations that are necessary for evaluating mechanisms. Using key architectural features from
active sites of metalloproteins as inspiration, my group has developed design approaches to
prepare systems that regulate local environments around a metal center. These systems are
used to study the activation of small molecules (e.g., O2 and H2O) that are essential in
maintenance of human health. This presentation will highlight our molecular designs from small
synthetic complexes to the use of larger, more diverse protein hosts.
28
26th
CRSI National Symposium in Chemistry
CRSI Medal Lectures
29
Arun Yethiraj
Professor Department of Chemistry University of Wisconsi-Madison USA
Email: [email protected]
Personnel Web page https://yethiraj.chem.wisc.edu/
30
CRSI Medal Lectures
Polymers in ionic liquids
Arun Yethiraj*
Professor Department of Chemistry University of Wisconsin-Madison USA
Ionic liquids have generated considerable excitement for their varied potential applications and their
interesting physical properties. The viability of ionic liquids (ILs) in materials applications is limited by
their lack of mechanical integrity, which may be provided by mixing them with a polymeric material.
Recent experiments on polymers in ILs have unearthed a wealth of interesting phenomena that raise
fundamental questions. This talk focuses on computational studies of PEO in imidazolium ILs. We
develop a physically motivated first principles force field for PEO and [BMIM] [BF4]; this force field is in
quantitative agreement with experiment with no adjustable parameters. Based on the same quantum
calculations we develop a hierarchy of united atom models with decreasing resolution and increasing
computational efficiency. Microsecond simulations are required to obtain converged properties of the
polymer, which displays a combination of ring-like and extended conformations. The simulations
show the existence of a lower critical solution temperature which arises from conformational
restrictions on the polymer molecules at low temperatures.
31
Jagadese J Vittal
Professor Department of Chemistry National University of Singapore Singapore Email: [email protected]
JJ Vittal received his BSc from the University of Madras in 1975, MSc from Madurai University in 1977
and PhD from Indian Institute of Science, Bangalore in 1982. After postdoctoral research at the
University of Western Ontario, Canada, he managed the X-ray facility for a few years. He then moved
to Singapore in 1997 where he is currently Professor in the Department of Chemistry, National
University of Singapore. He held a World Class University Chair Professorship at the Gyeongsang
National University, Jinju, South Korea (2009-2013). His major research interests include design &
synthesis of coordination polymers & metal-organic frameworks, solid-state supramolecular structural
transformations, solid state photochemical reactivity, single molecular precursor routes to various
metal chalcogenides, oxides bulk materials, films and nanocrystals, and battery materials. JJ
published about 500 research papers, reviews and book chapters with ~22000 citations and h-index
of 72. He co-authored ‗Crystal Engineering – A Textbook‘ with G.R. Desiraju and A. Ramanan. He
also co-edited two books on crystal engineering with E.R.T. Tiekink. He is a Fellow of Royal Society
of Chemistry and Singapore National Institute of Chemistry. He is an editorial board members of
several journals including Crystal Growth & Design and Scientific Reports. He won several awards
including Outstanding Chemist Award (2014), CRISP Award (2013), Outstanding Research Award
(2011) and Best Scientist Award (2007). JJ has been highlighted in Angewandte Author Profile
(2014). He is founder, chair and Organizing Committee member of Singapore National Crystal
Growing Challenge (1997-2014) to promote science through the art of growing crystals. He is an
international committee member of Worldwide IUCr Crystal Growing Competition for School Children
since 2014.
32
CRSI Medal Lectures
My Journey with Crystals under UV Light and beyond
JJ Vittal,
Professor
Department of Chemistry
National University of Singapore,SINGAPORE 117543.
The physical and chemical properties of the solids are directly related to their crystal structures. The
crystal engineering tools can be used to modify and fine-tune these properties. It is possible to design
organic crystals, coordination polymers and metal-organic framework materials with desired physical
properties like solubility, crystal bending, guest and gas sorption, storage, separation and
transportation, ion exchange, catalysis, magnetism (magnetic ordering, spin crossover), conductivity,
optics (multi-photon upconversion, luminescence and sensing, birefringence), negative thermal
expansion and processability. As more and more exotic new crystals are made, unexpected, unusual
and unpredictable properties have been discovered. In our laboratory we have encountered a number
of interesting properties such as structural transformations due to solvent exchange, change of
composition and dimensionality due to grinding, unexpected photoreactivity of organic crystals and
transition metal complexes and centrosymmetric MOFs showing second-order non-linear optical
properties. Mechanically responsive materials change their shape and size or move in space by light,
thermal, pressure or chemical energy. Of these, dynamic molecular crystals undergo various
movements like curling, crawling, jumping, leaping, hopping, popping, splitting, wiggling, and
exploding, when exposed to heat (thermosalient effect) or light (photosalient effect). These photo-
dynamic and thermal-dynamic crystals create new ways of transforming light and heat energy into
mechanical work. These effects are similar to popping of mustard seeds on hot oil or corn on hot
surfaces. Recently we have also observed such violent popping of single crystals of several metal
complexes during the [2+2] cycloaddition reaction under UV light showing the photosalient behavior.
In this talk some of these interesting and unusual physical and chemical properties of crystals will be
presented.
References:
1. Vittal, J.J.; Quah, H.S. Coord. Chem. Rev. 2017, 342, 1-18
2. Vittal, J.J.; Quah, H.S. Dalton Trans. 2017, 46, 7120-7140
3. Liu, M.; Quah, H.S.; Wen, S.; Wang, J. Kumar, P.S.; Eda, G.; Vittal, J.J.; Ji, W. J. Mater. Chem.
C 2017, 5, 2936-2941
4. Medishetty, R.; Park, I.H.; Lee, S.S.; Vittal, J.J. Chem. Commun. 2016, 51, 3989-4001.
5. Kole, G.K.; Vittal, J.J. Chem. Soc. Rev. 2013, 42, 1755-1775
33
26th
CRSI National Symposium in Chemistry
C.N. R. Rao National Prize for
Chemical Research Lecture
34
Giridhar U. Kulkarni
Director and Professor Centre for Nano and Soft Matter Sciences P.B.No. 1329, Prof. U.R. Rao Road Jalahalli - Bengaluru, Karnataka 560 013 - India. Email: [email protected]
G. U. Kulkarni is a Professor, Chemistry and Physics of Materials Unit, JNCASR and Director at
CeNS, Bangalore. He received his PhD at Indian Institute of Science in 1992 and has held
visiting/adjunct positions at Cardiff, Tokyo, TASC-INFM, Trieste; Scuola Normale Superiore, Pisa;
Purdue etc. His present research interests are focused on new strategies in synthesis of
nanomaterials, nanopatterning and nanodevice fabrication including of molecular systems. His
recipes emphasize the importance of simple design, near ambient working conditions, solution based
processing as well as low cost instrumentation. His group strives to translate nanoresearch finding
into affordable technology.
35
C.N. R. Rao National Prize for Chemical Research Lecture
Au decahedra: Unusual nucleus for unconventional lattices
Giridhar U. Kulkarni
Professor Centre for Nano and Soft Matter Sciences Bangalore, India Cubic lattice structure preferred by noble metals (e.g., Au, Ag, Pd and Pt) is thermodynamically highly
stable. Lower symmetry crystal structures are not known to stabilize relative to the face-centered
cubic (fcc) bulk even at high pressures. Observing a structural transformation in these metals is
therefore fundamentally exciting and can be possibly useful in tuning their otherwise noble behavior.
Recent explorations in this direction have focused on nanocrystals, as the energy needed for lattice
distortion is relatively low when the size is only a few nanometers. Inducing lattice strain at larger
length scales to cause structural transformation in the crystallite is indeed a herculean task. The same
has been achieved by us by stabilizing a decahedral nanocrystal via a simple synthetic method
involving a careful thermolysis of a metal-organic precursor in air.
The presentation will describe the synthesis of Au decahedra nuclei and the growth aspects.The
results obtained using in-housefacilities, on the morphology of the microcrystals, the unusual lattice
forms and their phase transitions, chemical reactivity etc. will be presented. Further, the insights
obtainedusing nanofocus synchrotron X-raybeamline on individual crystalliteson the distribution of the
various phases will be described.
References: 1. Mettala, G.; Radha, B.; Singh, D.; Kumar G. V. P.; Kulkarni, G.U. Sci. Rep., 2013, 3, 1793.
2. Mettela, G.; Bhogra, M.; Waghmare U.V.; Kulkarni, G.U. J.Am.Chem.Soc, 2015, 137, 3024.
3. G. Mettela and G. U. Kulkarni, Nano Research,2015, 9, 2925.
4. G. Mettela and G. U. Kulkarni, Cryst. Eng. Comm., 2015, 17, 9459.
5. G. Mettela, N. Mammen, J. Joardar, S. Narasimhan and G. U. Kulkarni, Nano Research, 2017,
10, 2271.
6. G. Mettela, S. A. Yesudas, A. Shukla, C. Bellin, V. Svitlyk, M. Mezouar, C. Narayana and G.
U. Kulkarni, Chem. Mater., 2017, 29, 1485.
7. G. Mettela, S. Kouser, C. Sow, S. T. Pantelides and G. U. Kulkarni, Angew. Chem. Int. Ed.,
2018, 57, 9018.
36
26th
CRSI National Symposium in Chemistry
CRSI Honorary Fellowship
Lecture
37
Sunney I. Chan
Institute of Chemistry, Academia Sinica, Taipei
Department of Chemistry, National Taiwan University, Taipei
E-mail: [email protected]
B.S. (1957) and Ph.D. (1960), University of California, Berkeley.；National Science
Foundation Postdoctoral Fellow, 1960-1961, Harvard University.；Assistant Professor,
1961-1963, University of California, Riverside.；Assistant Professor, 1963-1964;
Associate Professor, 1964-68; Professor, 1968-1992; George Grant Hoag Professor of
Biophysical Chemistry, 1992-2001; Hoag Professor, Emeritus, 2002-, California
Institute of Technology.；Honorary Professor, 1996-2015, Chinese University of Hong
Kong. ；Chair Distinguished Professor of Chemistry, 2007-2010; Distinguished
Research Chair Professor, 2010-2016, National Taiwan University.；Honorary Chair
Professor, 2012-14, National Ping Tung University of Education.；Chair Professor of
Bioinorganic Chemistry, 2013-16, National Chung Hsing University. ；Distinguished
Research Fellow and Director, 1997-1999; Distinguished Research Fellow, 1999-2011;
Distinguished Visit ing Fellow, 2011-15, Institute of Chemistry, Academia Sinica.；Vice
President, 1999-2003, Academia Sinica.；Director, National Research Program of
Genomic Medicine, 2001-03, National Science Council, Republic of China.；
38
CRSI Honorary Fellowship Lecture
Taming Methane: A Catalyst for Efficient and Selective Methane Oxidation under Ambient Conditions Sunney I. Chan
Institute of Chemistry, Academia Sinica, Taipei
Department of Chemistry, National Taiwan University, Taipei
ROC
The conversion of methane (CH4) into methanol (CH3OH) is extremely difficult chemistry.1
Methanotrophs metabolize CH4 as their sole source of carbon and energy, converting substantial
amounts of the CH4 produced by methanogenic bacteria into CH3OH in the presence of molecular
oxygen (O2). Over the past several decades, scientists have purified and studied in depth two
enzymes responsible for this chemistry.1
Based on our fundamental understanding of how the
particulate methane monooxygenase (pMMO) works, we have recently developed a biomimetic
catalyst capable of efficient and selective CH4 oxidation under ambient conditions.2-4
The catalytic
system consists of a CuICu
ICu
I tricopper cluster complex activated by O2 to produce a harnessed
oxene, which is rapidly inserted across one of the C—H bonds of the CH4 molecule in the transition
state when the substrate is bound to the hydrophobic pocket built into design of the tricopper
complex. Catalytic turnover is sustained by regenerating the functional catalyst with a molecule of
H2O2 for each CH4 molecule oxidized. The catalytic system can operate either as a homogeneous
catalyst in a solvent2-3
or reformulated as a quasi-heterogeneous catalyst by immobilizing the complex
within the nanochannels of mesoporous silica nanoparticles.4 The catalytic efficiency of the quasi-
heterogeneous catalyst is unprecedented. Progress has also been made toward developing this
catalytic system to accomplish the conversion of the light alkanes in natural gas into their
corresponding oxygenated products.5 The development of this catalytic system further for the control
of low pressure natural gas seeps and CH4 emissions from various human activities into the
atmosphere is under consideration.
References:
1. Wang, V. C.-C.; Maji, S.; Chen, P. P.-Y.; Lee, H. K.; Chan, S. I. Chem. Rev. 2017, 117,
8574−8621.
2. Chan, S. I.; Lu, Y.-J.; Nagababu, P.; Maji, S.; Hung, M.-C.; Lee, M. M.; Hsu, I.-J,; Minh, P. D.;
Lai, J. C.-H.; Ng, K. Y.; Ramalingam, S.; Yu, S. S.-F.; Chan, M. K. Angew Chem Int Ed 2013,
52, 3731–3735.
3. Nagababu, P.; Yu, S. S.-F.; Maji, S.; Ramu, R.; Chan, S. I. Catal Sci Technol 2014, 4, 930–
935.
4. Liu, C.-C.; Mou, C.-Y.; Yu, S. S.-F.; Chan, S. I. Energy Environ Sci 2016, 9, 1361–1374.
5. Liu, C.-C.; Janmanchi, D.; Wen, D.-R.; Oung J.-N.; Mou, C.-Y.; Yu, S. S.-F.; Chan, S. I. ACS
Sustainable Chem Eng. 2018, 6, 5431–5440.
39
26th
CRSI National Symposium in Chemistry
C.N.R. Rao Award Lecture
40
Richard Catlow
Department of Chemistry, University College London; School of Chemistry, Cardiff University; UK Catalysis Hub, Research Complex at Harwell, UK
Richard Arthur Catlow FRS FRSC FinstP (born 24 April 1947) is a British chemist, and professor
at University College London Previously, he was Director of the Davy Faraday Research Laboratory,
and Wolfson Professor of Natural Philosophy at the Royal Institution. Since 2016 he has served as
the foreign secretary of the Royal Society.
41
C.N.R. Rao Award Lecture
Modelling, Synchroton Radiation and Neutron Scattering Studies of Structure, Dynamics, and
Reactivity in Catalytic Systems
Richard Catlow
Department of Chemistry, University College London; School of Chemistry, Cardiff University; UK Catalysis Hub, Research Complex at Harwell, UK
The concerted use of synchrotron, neutron and modelling techniques has proved to be a powerful
approach in probing catalytic structures and processes at the molecular level. We will illustrate the
approach by recent applications to a range of systems including:
Hydrocarbon dynamics and reactivity in microporous catalysts, where we will describe how the
concerted use of modelling with neutron spectroscopy can yield unique information on
molecular transport and reactivity in hydrocarbon synthesis and auto-exhaust catalysts.
Structural and electronic properties of nano-particulate catalysts, including photocatalysts,
where the focus will be on the combination of modelling with synchrotron techniques in
developing detailed structural models of supported nano-particles.
Carbon dioxide and methane activation on oxide and carbide catalysts where the focus will be
on developing models for the activation mechanisms.
We will discuss how this powerful combination of techniques might be applied more widely in catalytic
science.
42
26th
CRSI National Symposium in Chemistry
Mizushina-Raman Lecture
43
Tahei Tahara
Chief Scientist
Molecular Spectroscopy Laboratory,
RIKEN, Japan. E-mail: [email protected]
Tahei Tahara graduated from the department of chemistry, the faculty of science, the University of
Tokyo, in 1984, and obtained his PhD degree in 1989 from the same university. He became research
associate of the University of Tokyo in 1989, and then moved to newly founded Kanagawa Academy
of Science and Technology (KAST) as research associate in 1990. In 1995, he joined Institute for
Molecular Science (IMS) as associate professor and started his own research group. He moved to
RIKEN as Chief Scientist in 2001 and has been the Director of Molecular Spectroscopy Laboratory
since then. He is also now Visiting Professor of Saitama University and Tokyo Institute of Technology.
His research interests are ultrafast spectroscopy, nonlinear spectroscopy and single molecule
spectroscopy of complex molecular systems. He received Award of Research Foundation for Opto-
Science and Technology (1995), Morino Science Award (2000), TRVS Young Researcher Award
(2001), IBM Japan Science Prize (2004), the JSPS Prize (2006), CSJ Award for Creative Work
(2012), Distinguished Asian Visiting Speaker Award of University of Alberta (2013), the
Commendation for Science and Technology by MEXT (Prize for Science and Technology) (2017), the
Spectroscopic Society of Japan Award (2017), Distinguished Scientist Awards of the Japan Society
for Molecular Science (2017), Award for Outstanding Contribution to Raman Spectroscopy (2018),
TRVS Lifetime Achievement Award (2019), Mizushima-Raman Lecturer (2020). He is currently
President of Japan Society for Molecular Science
44
Mizushina-Raman Lecture
Time-Domain Raman Spectroscopy and Its Application to Ultrafast
Photochemical/Photobiological Reactions
Tahei Tahara
Molecular Spectroscopy Laboratory,
RIKEN, Japan.
Since its discovery 90 years ago, Raman spectroscopy has been developing continuously, and it is
now one of the most important spectroscopies which is extensively utilized in various fields of science
and technology. In traditional Raman spectroscopy, the energetically-shifted inelastic light scattering
(Raman scattering) is measured, and the energy shift from the excitation light provides information
about the vibrational energy of the molecules. On the other hand, using an ultrashort optical pulse that
has a duration shorter than the vibrational period of molecules, we can carry out time-domain Raman
spectroscopy that induces coherent nuclear motion of the molecule with the impulsive stimulated
Raman process and observes Raman-active vibrations directly in the time domain. In principle, the
information obtainable with time-domain Raman spectroscopy is equivalent to that obtained by
ordinary frequency-domain Raman spectroscopy. However, because time-domain Raman
spectroscopy is performed with only femtosecond pulses, we can trace the temporal change of the
molecular vibrations with a femtosecond accuracy by combining it with a femtosecond pump pulse
that starts chemical reactions.1-3
In this lecture, I talk about the recent progress of our research about
femtosecond time-domain Raman spectroscopy. A newly developed apparatus using 7-fs optical
pulses allowed us to investigate the ultrafast dynamics of complex molecular systems such as the
chromophore isomerization in photoreceptor proteins and the chemical bond formation process in
molecular assemblies.4-6
We also showed the possibility of multi-dimensional time-domain Raman
spectroscopy that reveals the anharmonicity of reactive excited-state potential energy surfaces of
complex molecules.7
References:
1. Fujiyoshi, S; Takeuchi, S; Tahara, T. J. Phys. Chem. A, 2003, 107, 494-500.
2. Cerullo, G.; Lüer, L.; Manzoni, C.; S. Silvestri, S.; Shoshana, O.; Ruhman, S. J. Phys. Chem.
A, 2003, 107, 8339-8344.
3. Takeuchi, S.; Ruhman, S.; Tsuneda, T.; Chiba, M.; Taketsugu, T.; Tahara, T. Science 2008,
322, 1073-1077.
4. Fujisawa, T; Kuramochi, H.; Hosoi, H.; Takeuchi, S.; Tahara, T. J. Am. Chem. Soc. 2016, 138,
3942-3945 (2016).
5. Kuramochi, H.; Takeuchi, S.; Yonezawa, K.; Kamikubo, H.; Kataoka, M.; Tahara, T. Nat.
Chem. 2017, 9, 660-666.
6. Kuramochi, H.; Takeuchi, S.; Iwamura, M.; Nozaki, K.; Tahara, T. J. Am. Chem. Soc. 2019,
141, 19296-19303.
7. Kuramochi, H.; Takeuchi, S.; Tahara, T, Sci. Adv. 2019, 5, eaau4490 /1-7.
45
26th
CRSI National Symposium in Chemistry
3rd
Charusita Chakravarty
Memorial Lecture
46
Srabani Taraphder
Department of Chemistry
Indian Institute of Technology Kharagpur, India
E-mail: [email protected]
Srabani Taraphder (nee Roy) completed B.Sc. Chemistry (Hons.) from Presidency College, Kolkata
and joined the Integrated M.S.-Ph.D. program in Chemistry at Indian Institute of Science, Bangalore.
She completed her PhD degree in 1996 in the field of theoretical physical chemistry under the
supervision of Prof. Biman Bagchi at the Solid State and Structural Chemistry Unit of IISc Bangalore.
Srabani joined as a member of the faculty at the Department of Chemistry, Indian Institute of
Technology Kharagpur in 1996. She is currently a Professor at the same department. Her research
activity focuses on computer simulation studies of chemical reactions in complex systems.
Her academic profile also includes the following.
Visiting Fellow, Harischandra Research Institute, Allahabad.
Visiting fellow, National Institutes of Health, USA.
Visiting faculty and IUSSTF fellow, Henry Eyring Center for Theoretical Chemistry, Department of
Chemistry, University of Utah, USA.
Young Associate of the Indian Academy of Sciences, Bangalore.
Regular Associate, International Centre for Theoretical Physics, Trieste, Italy.
Fellowship of the Human Frontier Sciences Program to Instituto de Quimica Fisica Rocasolano,
CSIC, Madrid, Spain
INSA Teachers Award (2018) of the Indian National Science Academy, New Delhi.
47
3rd
Charusita Chakravarty Memorial Lecture
Reaction Coordinate, Free Energy and Kinetics in an Enzyme Catalysed Proton Transfer Reaction
Srabani Taraphder* Department of Chemistry Indian Institute of Technology Kharagpur, India
The molecular mechanism of an enzyme catalysed proton transfer event involves the transfer of
excess proton(s) along dynamic pathways comprised of hydrogen bonded networks of amino acid
residues and water molecules. The importance of enzyme structure and dynamics on such proton
transfer steps is well demonstrated by human carbonic anhydrase II (HCA II), which has long served
as a prototype for enzymes containing a rate determining proton transfer step. In this lecture, we shall
present a quantitative description of the catalysis by HCA II. For each step in the multi-step catalysis,
the reaction coordinate is derived using machine learning methods to reduce the data available from a
wide range of relevant structural, mutation, and kinetic experiments supplemented by a large number
of theoretical and computer simulation studies. The free energy and rate constants estimated along
the reaction coordinates allow us to determine the mechanism that corresponds to the experimentally
observed catalytic rate constant of HCA II.
References:
1. Paul, T.K.; Taraphder, S. (submitted, 2020).
2. Paul, S.; Paul, T. K.; Taraphder, S. J. Mol. Graph. Mod. 2019, 90, 18-32.
3. Paul, S.; Paul, T. K.; Taraphder, S. J. Phys. Chem. B 2018, 122, 2851-2866.
4. Paul, T. K.; Taraphder, S. J. Phys. Chem. B 2015, 119, 11403-11415.
5. Roy, A.; Taraphder, S. J. Phys. Chem. B 2009, 113, 12555-12564; ibid 2008, 112, 13597-
13607; ibid 2007, 111, 10563-10576.
48
26th
CRSI National Symposium in Chemistry
Lifetime Achievement
Award Lecture
49
T. Ramasami
Former Secretary to Government of India
Ministry of Science and Technology
Nayudamma Abdul Wahid Chair Professor
Department of Leather Technology, AU
CSIR-Central Leather Research Institutte
Adayr, Chennai 600 020
Thirumalachari Ramasami is the former Indian Science and Technology Secretary. He assumed
charge in May 2006. Prior to this assignment, he served as the Director of the Central Leather
Research Institute, Chennai, India. He is a distinguished researcher and leather scientist. He was
awarded India's National Civilian Honour the Padma Shri for excellence in Science and Engineering in
2001, and the Padma Bhushan in 2014.
He was awarded the Shanti Swarup Bhatnagar Award, the
highest award for science in India, for notable and outstanding research in Chemical Sciences in
1993.
50
Lifetime Achievement Award Lecture
A Story of an evolution of a chemist
T. Ramasami
Former Secretary to Government of India
Ministry of Science and Technology
Nayudamma Abdul Wahid Chair Professor
Department of Leather Technology, AU
CSIR-Central Leather Research Institute, Adayr, Chennai 600 020
Knowledge pyramid in science is built on the foundation of curiosity, desire to know, explore un
chartered areas and seek truth. Framing the right questions and seeking truthful answers forms the
language of science. When such questions and answers deal with real life systems, complexity of
questions, answers and systems impacts the professional path of a scientist.
Three aspects of scientific research namely discovery, solution and sustainability of solutions become
important in different stages of a professional. During discovery phase of research, understanding
chemical phenomena becomes a focus of studies. Understanding factors controlling mechanisms of
substitution and electron transfer reactions in transition metal complexes and implications of
chemistry of chromium in real life systems formed a major thrust during the discovery phase of life.
Some key lessons learnt from understanding would be shared. Curiosity and passion for excellence
were driving factors in that early career phase of life.
At mid-career stage, solution science had become a necessity. Scientific research was then driven by
relevance of the solutions for solving real life problems faced by chromium based industries and
tanneries. Viable and sustainable scientific solutions to many industrial problems based on the
applications of chemistry had to be designed, developed and delivered. ―Do Ecology‖ solutions to
environmental problems associated with heavy metal ions and leather processing activity called for
deeper understanding of under pinning chemistry. Many were developed and implemented in
commercial scale. An industrial catastrophe faced by leather industry in Tamil Nadu was averted
through the deployment of viable Do ecology solutions. Saving of jobs and creating employment
through technological research were fulfilling.
Late career efforts were focused upon service as a chemist. Case studies of some real life solutions
to societal problems through applications of broader science would be presented. The talk is planned
as a voyage into the ocean of knowledge with chemistry as leading light, service as the purpose of the
journey.
In short, continuing journey of a chemist is proposed to be shared through his learnings at various
stages of professional life in an anecdotal format.
51
26th
CRSI National Symposium in Chemistry
Silver Medal Lectures
52
Vijayamohanan K Pillai
Indian Institute of Science Education and Research, Tirupati
C/o Sree Rama Engineering College (Transit Campus),
Rami Reddy Nagar, Karakambadi Road,
Mangalam (P.O.) Tirupati -517507, Andhra Pradesh, INDIA
Email: [email protected]
Prof. Vijayamohanan K Pillai is a leading Electrochemist from India, who after receiving his Ph.D from
the Indian Institute of Science, Bangalore, worked in many areas of electrochemical power sources,
electrochemical sensors and bio-electrochemistry for about two decades at the National Chemical
Laboratory, Pune.
He has authored over 260 publications and 28 patents related to many innovations in both
Electrochemistry and Materials Chemistry, while advising about 23 Ph.D. students in Materials
Electrochemistry. His group has developed highly sensitive nanostructured platinum electrocatalysts
for CO oxidation and Polymer Eelectrolyte Fuel Cells (PEMFC) using Nafion-based composite
membranes with functionalized carbon nanotubes and graphenes. His research interests include
Materials Electrochemistry, functionalization of carbon nanotubes/graphene nanoribbons and two
dimensional quantum dots as electrocatalysts for fuel cells, supercapacitors and rechargeable
batteries.
He has received many honors and awards like The MRSI Medal, Bangalore in 1996 and CRSI Bronze
Medal in 2004. He was a Member of the Editorial Board of Bulletin of Materials Science (2005-2016),
Electrocatalysis (2012 onwards) and Scientific Reports (2015 onwards) and is a Fellow of the Indian
Academy of Sciences since 2008 and the Indian National Science Academy (2018). He has been an
"Erudite visiting professor" at MG University, Kottayam since 2011 and has given ―Professor K.S.G.
Doss Memorial Lecture in 2011‖, ―Professor Gurumurthy Mangalam Endowment Lecture, Annamalai
University‖ in 2012, ―R.K. Barua Memorial Lecture at the Gauhati University‖ in 2013, ―Prof. Chelikani
Chiranjeevi Endowment Lecture Award, Andhra University‖ in 2015, ―IICT-Avon Padmashri Dr. G S
Sidhu Chemcon Distinguished Speaker Award-2016‖, ―Prof. B. Thimme Gowda endowment lecture
2015-16‖, Mangalore University, ―National Prize for Research on Energy Materials and Devices‖ by
JNCASR, 2016, ―Prof. T. L. Rama Char Memorial Lecture - ECS India‖, 2016, ―MRSI-ICSC
Superconductivity and Materials Science Annual Prize‖, 2016, ―Dr. K T Achaya Memorial Award‖ by
OTAI, 2017 and ISCB Award for Excellence (Chemical Sciences), 2019. He has also visited many
foreign countries like US, Germany, France, Finland, Japan, China, Australia for giving invited
lectures on many topics in Materials Electrochemistry and Electrochemical Energy Storage. In
addition to being Director of CSIR-CECRI (April 2012 – October 2018), he held the additional charge
as Director, CSIR-NCL, Pune from June 2015 to February 2016.
He is at present working as the dean (R&D) and chair of Chemistry at IISER-Tirupati and may be
contacted at [email protected], or [email protected].
53
Silver Medal Lectures
Phosphorene Quantum Dots: Electrochemical Preparation, Doping and Possible Applications
Vijayamohanan K Pillai
Indian Institute of Science Education and Research, Tirupati
Mangalam (P.O.) Tirupati -517507, Andhra Pradesh, INDIA
Phosphorene quantum dots (PQDs) have emerged as a fascinating class of two-dimensional
materials for potential applications in optoelectronics, catalysis, and sensing. In addition to size size-
dependant tuning of their electronic properties, the possibility of heteroatom doping at room
temperature and surface functionalization to improve poor stability make them especially useful for
many optical applications. This lecture addresses various aspects of the structural distortion of black
phosphorus (BP) to phosphorene quantum dots during this transformation using results obtained
from transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy.
Further,first-principles-based density functional theory, calculations on oxygenated and
nonoxygenated PQDs augment the experimental observations that an optimum oxygen content
maintains the structural integrity of PQDs, above which the structural robustness of PQDs is
drastically diminished. Role of nitrogen doping on their optical and electocatalytic properties is also
discussed...
References:
1. A single-step, electrochemical synthesis of nitrogen doped blue luminescence
phosphorene quantum dots, Manila et al., Chem. Com.54 (2018)11733
2. Role of Structural Distortion in Stabilizing Electrosynthesized Blue-Emitting Phosphoren
Quantum dots, Manila et al J. Phys. Chem. Lett. 10 (2019) 973-980.
54
Subrata Ghosh
School of Chemical Sciences Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India e-mail: [email protected]
Professor Ghosh obtained Ph. D. in 1978 under the supervision of Late Professor U. R. Ghatak at
Indian Association for the Cultivation of Science (IACS), Calcutta. During his Ph. D. he joined the
Department of organic Chemistry, IACS as Research Assistant in 1977. He worked as a postdoctoral
fellow at Case Western Reserve University with Professor R. G. Salomon as the mentor during 1979-
1981 and 1984-1986 on study leave from IACS. He joined the Department of Organic Chemistry at
IACS as Lecturer in1982 and began his independent research career. Subsequently he was promoted
to Reader in 1987, Professor in 1994 and Senior Professor in 2005. . He also served IACS as Dean
during 2009-2012. He was a visiting scientist at Liecester University for the period October-
December, 1997 under INSA-Royal Society Exchange Program. He served as an Editorial Board
Member in Journal of Chemical Sciences. He was a member in DST Management Advisory
Committee for young Scientists, DST Program Advisory Committee (Organic Chemistry) and in
Sectional Committee (Chemical Sciences) of Indian Academy of Sciences, Bangalore. He retired from
service in April, 2014. Since then he is continuing his research as a J. C. Bose National Fellow.
Research interest includes total synthesis of natural products, development of new synthetic
methodologies, cycloaddition reactions, olefin metathesis, Chiron approach to asymmetric synthesis
etc.
55
Silver Medal Lectures
Natural Products Synthesis – Some Fascinating Aspects
Subrata Ghosh
School of Chemical Sciences Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
Natural products have long been recognized as an invaluable source for the discovery of numerous
therapeutic agents. The structural diversity and complexity coupled with therapeutic potential, natural
products have stimulated great deal of interest for development of synthetic routes. Bridged- and
fused polycyclic systems with highly complex molecular structures are frequently encountered in a
variety of natural products. Some of the compounds of contemporary interest include
shinortriterpenoids such as schintrilactones 1, diterpene ingenol 2, artemisinin 3 and gracilioether F 4.
These compounds are associated with a multitude of bio-activities beneficial to mankind. For
example, schintrilactones exhibit anti-HIV activity while few derivatives of ingenol show anti-cancer
activity. Compound 3 is an anti-malarial while 4 possesses antifungal properties. Synthesis of these
complex molecular structures is a formidable task. Some fascinating aspects observed during our
efforts1-5
towards the synthesis of these and related compounds will be presented.
References:
1. Malik, C. K.; Ghosh S. Org. Lett. 2007, 9, 2537-2540.
2. Malik, C. K.; Yadav, R. N.; Drew, M. G. B.; Ghosh, S. J. Org. Chem. 2009, 74, 1957-1963.
3. Maity, S.; Matcha, K.; Ghosh, S. J. Org. Chem. 2010, 75, 4192-4200.
4. Mondol, S.; Yadav, R. N.; Ghosh, S. Org. Lett. 2011, 13, 6078-6081.
5. Datta, R.; Ghosh, S. J. Org. Chem. 2017, 82, 7675-7682.
56
26th
CRSI National Symposium in Chemistry
Bronze Medal Lectures
57
Ranjani Viswanatha
International Centre for Materials Science
Jawaharlal Nehru Centre for Advanced Scientific Research
Jakkur, Bangalore 560064
Email: [email protected]
Ranjani Viswanatha is currently working as an associate professor at Jawaharlal Nehru Centre for
Advanced Scientific Research. She did her Ph. D. at the Indian Institute of Science under the
guidance of Prof. D. D. Sarma on the growth in solution and electronic structure of
nanocrystals. Subsequent to her Ph.D. work, she has been worked as a postdoctoral fellow at Prof.
Xiagong Peng‘s laboratory at the University of Arkansas and at the Los Alamos National Lab in Prof.
Victor Klimov's group before joining JNCASR. Her work revolves around some interesting behavior of
transition metal dopants in nanocrystals qualitatively different from the bulk. Her work has been
published in leading journals and she has been awarded several national awards like Karnataka State
C V Raman award, MRSI medal, DST Young Nanoscientist award, Sheikh Saqr Fellowship, founding
member of Indian National Young Academy of Science, the INSA young scientist medal and chosen
as a young associate of Indian Academy of Science, founder member of Indian National Young
Academy of Science among many others. She is also a reviewer in many of the leading journals and
has given several talks in leading conferences.
58
Bronze Medal Lectures
Mn emission: Energy transfer or Charge transfer
Ranjani Viswanatha International Centre for Materials Science Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore 560064
Quantum dots, wherein size-dependent properties are often observed, are of great scientific interest
as they effectively act as a bridge between the bulk properties and the atomic or molecular properties.
Doping transition metal ions in quantum dots provide great flexibility in controlling electronic and
magnetic interactions via growth-controlled ―engineering‖ of wave functions giving rise to interesting
properties, including lasing, giant magneto-optical properties. Manganese is one of the most
extensively studied dopants in this category. This interest is primarily piqued by the interesting
orange emission arising from the Mn d-d transition. While the practical observation and
manifestations of this emission has led to several applications like photo-magnetism, the physics of its
origin has continued to intrigue many researchers with its spin forbidden nature. Two main concepts
that have been used to understand this emission is the energy transfer and charge transfer. Most of
the literature in this field now believe it to be an energy transfer process. In this talk, I am going to
discuss the typical signatures of energy and charge transfer and various recent experimental
observations that cannot be explained using energy transfer.1,2
I also present some theoretical results
demonstrating the viability of charge transfer.3
References:
1. R. Viswanatha; J. M. Pietryga; V. I. Klimov; S. A. Crooker, Phys. Rev. Lett. 2011, 107,
067402.
2. K. R. Pradeep; D. Acharya; P. Jain; K. Gahlot; A. Yadav; A. Cammelini; M. Zavelani-Rossi; G.
Cerullo; C. Narayana; S. Narasimhan; R. Viswanatha; ACS Ene. Lett. (In Press).
3. K. Gahlot; K. R. Pradeep; A. Cammelini; G.Sirugu; G. Cerullo; M. Zavelani-Rossi; A. Singh;
U.V. Waghmare; R. Viswanatha, ACS Ene. Lett. 2019, 4, 729-735.
59
Manmohan Kapur
Department of Chemistry, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal 462066, INDIA. E-mail: [email protected]
Personel webpage: https://sites.google.com/a/iiserb.ac.in/mk-group-iiserb/
60
Bronze Medal Lectures
Transition-metal-catalyzed Distal and Remote Functionalizations
Manmohan Kapur
Department of Chemistry, Indian Institute of Science Education and Research Bhopal Bhopal Bypass Road, Bhauri, Bhopal 462066, INDIA.
The site-selective functionalization of distal or remote positions with respect to a reactive functional
group in an organic framework, has always been a synthetic challenge for chemists.1 Achieving this
by the rational design of the substrate to be functionalized, comes with positional-selectivity
challenges of its own. The C-H functionalization of organic molecules is now a quite well-developed
field. The transition-metal mediated C-H functionalization of bonds in the immediate vicinity of Lewis-
basic directing groups is one approach that has been widely-utilized for proximal bond
functionalization. This directing-group approach has also been utilized for C-H functionalization of
distal bonds using extended tethers. In another approach, using an extended -system conjugated to
a heteroatom, distal C-H functionalizations can be achieved, often by Pd-catalysis.
The remote functionalization of -conjugated systems via low-valent transition-metal catalysis has its
own challenges, in terms of selectivity of the sp2 bond being functionalized. This talk shall focus on
these aspects, Pd-catalyzed distal and remote functionalization of extended sp2-systems and our
recent contributions to these areas. 2-3
References:
1. Vasseur, A.; Bruffaerts, J.; Marek, I. Nature Chemistry, 2016, 8, 209–219.
2. (a) Pawar, G. G.; Singh, G.; Tiwari, V. K.; Kapur, M. Adv. Synth. Catal. 2013, 355, 2185-2190;
(b) Tiwari, V. K.; Pawar, G. G.; Das, R.; Adhikary, A.; Kapur, M. Org. Lett. 2013, 15, 3310-
3313. (c) Tiwari, V. K.; Pawar, G. G.; Jena, H. K.; Kapur, M. Chem. Commun. 2014, 50, 7322-
7325. (d) Tiwari, V. K.; Kamal, N.; Kapur, M. Org. Lett. 2017, 19, 262-265. (e) Kumar, P.;
Kapur, M. Org. Lett. 2019, 21, 2134-2138. (f) Das, R.#; Khot, N. K.
#; Deshpande, A. S.; Kapur,
M. Chem. -Eur. J. 2019, 25, 0000 (doi.org/10.1002/chem.201904512) (#equal contribution).
3. Saini, G.; Mondal, A.; Kapur, M. Org. Lett. 2019, 21, 9071-9075.
61
Rajakumar Balla
Department of Chemistry,
Indian Institute of Technology Madras,
Chennai 600036, India
Rajakumar Balla Born in a very remote village of the Srikakulam District of Andhra Pradesh to Sri
Suryanarayana and Smt. Jayalakshmi in 1971. Obtained B. Sc from Sri Durgaprasad Sharaf college
of arts and applied sciences, Sriram Nagar, Garividi of Vizianagaram District of Andhra Pradesh.
Studied M. Sc in Chemistry in the School of Chemistry, Andhra University Visakhapatnam. Introduced
to the field of gas phase physical chemistry by Prof. E. Arunan at the Department of Inorganic and
Physical Chemistry of the Indian Institute of Science Bangalore and obtained Ph. D in 2002 under his
supervision. Further, pursued research in the area of the atmospheric chemistry and physics as a
post doctoral researcher under the leadership of the famous scientist Prof. Dr. A. R. Ravishankara at
the National Oceanic and Atmospheric Administration (NOAA), Boulder, Colorado, U. S. A. Returned
to India in 2006 and joined the Department of Chemistry at the Indian Institute of Technology Madras
as an Assistant Professor and currently working as a Professor.
62
Bronze Medal Lectures
Measurement of absorption cross-sections and kinetics of radicals relevant to the Earth’s
atmosphere using Cavity Ring Down Spectroscopy
B. Rajakumar
Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036
When a compound is released into the Earth‘s atmosphere, on one hand it undergoes photo
dissociation when exposed to the light and on the other hand it reacts with very important oxidizing
agents. Therefore, the loss of a compound depends on both photo-physical as well as photo-chemical
processes, in the Earth‘s atmosphere. Photo induced radical chemistry plays a very important and
vital role in the Earth‘s atmosphere in terms of Global Warming, Ozone loss and Climate change. As
aliphatic as well as aromatic hydrocarbons takes the major stack in the chemical composition of the
Earth‘s atmosphere, it is essential to understand the chemistry initiated by them in the presence of
light. On these grounds, measurement of absorption cross-sections of important radicals such as
propionyl and phenyl radicals were undertaken as a first step in the process of understanding their
photo-chemical properties as well as kinetics with important molecules. Cavity Ring Down
Spectroscopy (CRDS), which is essentially a supersensitive optical spectroscopic tool works on the
principle of Fabry-Perrot cavity is used to measure the absorption cross-sections and kinetics with
important molecules. The CRD spectrometer was built in our research lab at IIT Madras. The
propionyl radical, CH3CH2CO, which is of importance in both atmospheric and combustion chemistry
rapidly converted to propionyl peroxy radical via its reaction with O2 which, in turn leads to the
formation of peroxypropionylnitrate4 (PPN, CH3CH2C(O)O2NO2). PPN is an atmospheric reservoir for
NOX (NO+NO2). PPN concentrations of up to 4 ppb have been measured and reported in urban
areas5. The visible absorption spectrum of the propionyl radical, CH3CH2CO was measured between
555 and 595 nm at 298 K using cross photolysis cavity ring-down spectroscopy. In addition to this,
absorption cross-sections of yet another important radical, Phenyl radical was measured and they
were used to measure the kinetics with methanol. The details of the experimentation and results will
be discussed in the conference.
Reference:
1. Koushik Mondal, Revathy Kaipara and B. Rajakumar. J. Phys. Chem. A 2019, 123, 9682-
9692
63
Seergazhi Gopalan Srivatsan Indian Institute of Science Education and Research (IISER), Pune, India 411008 Email: [email protected]
S. G. Srivatsan received his master‘s degree in Chemistry from Indian Institute of Technology,
Madras in 1995 and Ph. D. in Bioorganic Chemistry from Indian Institute of Technology, Kanpur in
2003 under the supervision of Prof. Sandeep Verma. He was an Alexander von Humboldt
postdoctoral fellow with Prof. Michael Famulok at University of Bonn, Germany, where he developed
catalytic RNAs and pharmacophores that target protein-RNA complexes and their enzyme activity.
Subsequently, he joined Prof. Yitzhak Tor group as a postdoctoral fellow in University of California,
San Diego. He joined Indian Institute of Science Education and Research (IISER), Pune in November
2008. He is currently a Professor and Wellcome Trust-DBT India Alliance Senior Fellow. He recently
received the CDRI AWARDS–2019 for Excellence in Drug Research and serves as an Editorial
Advisory Board member of ACS Bioconjugate Chemistry. He is also nominated to receive the
Chemical Research Society of India Bronze medal for 2020. His research interests lie in the area of
nucleic acid chemistry and biophysics, particularly in the development of nucleoside probes for
studying nucleic acid structure and function, functionalized nucleoside-based self-assemblies, and
nucleic acid labeling and imaging tools.
Webpage: http://www.iiserpune.ac.in/~srivatsan
64
Bronze Medal Lectures
Probing Mood (Structure) Swings of Non-Canonical Nucleic Acid Motifs
Seergazhi Gopalan Srivatsan Indian Institute of Science Education and Research (IISER), Pune, India 411008 Numerous biophysical tools have provided efficient systems to study nucleic acids. However, our
current understanding on how nucleic acid structure complements its function, particularly in cellular
environment, is limited. This general limitation is largely due to the lack of probes that can be used in
both cell-free and cellular assays, and in more than one biophysical technique. Hence, correlating the
information obtained under equilibrium conditions, in solid state and in cells becomes very difficult
using uniquely-labeled oligonucleotide sequences. In this context, moving away from the tradition
approach of ―one label one technique‖ we adopted an innovative approach to investigate the nucleic
acid structure and function in cell-free and cellular environments by using conformation-sensitive
multifunctional nucleoside analog probes. Based on this strategy, we have developed nucleoside
analogs equipped with two or more labels (eg., fluorophore, NMR isotope label and X-ray
crystallography phasing atom), which serve as common probes for analyzing nucleic acid motifs
simultaneously by using a combination of fluorescence, NMR and X-ray crystallography techniques.1-4
In this presentation, design and synthesis of multifunctional nucleoside probes, and their utility in
investigating the structure and ligand binding properties of a therapeutically important non-canonical
nucleic acid motif (G-quadruplex) in real time, in 3-dimension and in native cellular environment will
be discussed.
References:
1. Nuthanakanti, I. Ahmed, S. Y. Khatik, K. Saikrishnan, S. G. Srivatsan, Nucleic Acids Res., 47,
6059 (2019).
2. S. Manna, D. Sarkar, S. G. Srivatsan, J. Am. Chem. Soc., 140, 12622 (2018).
3. A. Nuthanakanti, M. A. Boerneke, T. Hermann, S. G. Srivatsan, Angew. Chem. Int. Ed., 56, 2640
(2017).
4. A. A. Tanpure, S. G Srivatsan, Nucleic Acids Res., 43, e149 (2015).
65
Mahesh Hariharan
School of Chemistry, IISER-TVM
E-mail: [email protected]
Dr. Mahesh Hariharan has completed his Ph.D from National Institute for Interdisciplinary Science
and Technology, Trivandrum, Kerala under the supervision of Prof. Danaboyina Ramaiah in the year
2006. He did his postdoctoral research from Northwestern University, Illinois, USA under Prof.
Frederick D. Lewis in the year 2007-2009. He has joined in IISER-TVM as an assistant professor in
the year of 2009. He has been promoted to Associate professor in the year of 2014. He is also a
visiting professor in University of Wuerzburg, Germany and Montana State University, Montana, USA.
He is associated with Royal Society of Chemistry; American Chemical Society; Asian and Oceanian
Photochemistry Association; Inter-American Photochemical Society; European Photochemistry
Association; International Association of Advanced Materials; Chemical Society of Japan, Japanese
Photochemistry Association, Chemical Research Society of India; Materials Research Society of
India; Indian Society for Radiation and Photochemical Sciences, Photosciences Research Society of
India; Kerala Academy of Sciences, India. He has published 57 publications in reputed international
journals. He has completed two research grants from DST and DBT. Currently, he has two ongoing
projects.
66
Bronze Medal Lectures
Ultrafast Excited State Dynamics of Twisted Aromatics
Mahesh Hariharan
School of Chemistry, IISER-TVM
Self-assembling of organic chromophoric systems into elegant supramolecular architectures with
emergent properties has received prodigious attention in recent years.1 The notion of ‗emergence
upon assembly‘ is evidenced in the unusual photoexcited state dynamics exhibited by chromophoric
assemblies. In the first example, a naphthalene-naphthalimide donor-acceptor (D-A) dyad assembled
into segregated D-A stacks in the crystalline state. The photo-induced charge separated state in the
aggregate state lasts 10,000 times longer than the monomeric dyad. The femtosecond transient
absorption spectra depicted the spectroscopic signature for naphthalene dimer radical cation
indicating the migration of charges through the stacks.2 In the second example, we report the
crystalline evidence for Greek cross‐dipole (α=90°) stacking of 1,7‐dibromoperylene‐3,4,9,10‐
tetracarboxylic tetrabutylester (PTE‐Br2) displaying null excitonic coupling and thereby monomeric
optical behavior. Additionally, the semi‐classical Marcus theory of charge‐transfer rates predicted a
selective hole transport phenomenon in the orthogonally stacked PTE‐Br2.3 In the third example, we
showcase a radial assembly of 1,8-dibromonaphthalene(2,6-diisopropylphenyl)imide (NIBr2) in
crystalline phase driven by hexabromine synthon.4
NIBr2 exhibits ultrafast intersystem crossing5 and
solid-state room temperature phosphorescence. We believe the fundamental understanding of
noncovalent interactions dictating the unorthodox assembly of chromophores6-7
and probing of
emergent properties are paramount for the rational design and construction of robust functional
materials.
Figure. Representative strategies adopted in our group to spatially organize organic chromophores for emergent properties.
References:
1. Cheriya, R. T.; Mallia, A. R.; Hariharan, M. Energy Environ. Sci. 2014, 7, 1661.
2. Mallia, A. R.; Salini, P. S.; Hariharan, M. J. Am. Chem. Soc. 2015, 137, 50, 15604.
3. Sebastian, E.; Philip, A. M.; Benny, A.; Hariharan, M. Angew. Chem., Int. Ed. 2018, 57, 15696.
4. Niyas, M. A.; Ramakrishnan, R.; Vijay, V.; Sebastian, E.; Hariharan, M. J. Am. Chem. Soc. 2019,
141, 4536.
5. Nagarajan, K.; Mallia, A. R.; Muraleedharan, K.; Hariharan, M. Chem. Sci. 2017, 8, 1776.
6. Ramakrishnan, R.; Niyas, M. A.; Lijina, M. P.; Hariharan, M. Acc. Chem. Res. 2019, 52, 3075-3086
7. Mohan, A; Sasikumar, D.; Bhat, V.; Hariharan, M. Angew. Chem., Int. Ed. 2020, 59, 2-9.
67
Ashwani K. Tiwari Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246 Email: [email protected]
Ashwani K. Tiwari is a Professor of Theoretical Chemistry at the Indian Institute of Science Education
and Research (IISER) Kolkata. His research interests involve the quantum dynamics of laser–
molecule and molecule–metal surface interactions. He received his Ph.D. in theoretical chemistry
working under the supervision of Prof. N. Sathyamurthy at the Indian Institute of Technology, Kanpur,
in 2007. During the period May 2007–April 2008, he was a postdoctoral fellow with Prof. Niels E.
Henriksen at the Technical University of Denmark. From May 2008 to April 2010, he was a
postdoctoral fellow with Prof. Bret Jackson at the University of Massachusetts, Amherst. He joined
IISER Kolkata as an Assistant Professor in the year 2010, became Associate Professor in 2015 and
full Professor in 2019.
68
Bronze Medal Lectures
Effects of Mode-Mode Coupling on the Dissociation Dynamics of H2O and CH4 on Metal
Surfaces
Ashwani K. Tiwari*
Department of Chemical Sciences, Indian Institute of Science Education and Research Kolkata, Mohanpur 741246
*
Dissociation of H2O on metal surfaces is rate-limiting step in many industrially important reactions. In
a few recent experiments, it has been observed that dissociations of H2O on metal surfaces is mode-
selective. In other words, this reaction is not statistical in nature and therefore, one cannot use
transition state based theory to get insights of this reaction. Our quantum dynamical calculations show
that mode-mode coupling along reaction path is the key factor in deciding the quantum of mode-
selectivity in this reaction.
Fig1. Dissociation sticking probabilities as a function of incident energies for the vibrational ground
state and several initial vibrationally excited states of H2O on Ni(111) surfaces at 300K.
References:
1. A. Mondal, H. Seenivasan, and A. K. Tiwari, J. Chem. Phys. 137, 094708 (2012)
2. P.M. Hundt, B. Jiang, M.E. van Reijzen, H. Guo, and R.D. Beck, Science 344, 504 (2014).
3. H. Seenivasan, B. Jackson and A. K. Tiwari J. Chem. Phys, 146, 074705 (2017).
4. D. Ray, S. Ghosh and A. K. Tiwari J. Phys. Chem. A, 122, 5698-5709 (2018)
5. S. Gosh, D. Ray, and A.K. Tiwari, J. Chem. Phys150, 114702 (2019).
6. D. Migliorini, F. Nattino, A. K. Tiwari and G-Jan. Kroes J. Chem. Phys., 149, 244706 (2018)
69
Ekambaram Balaraman
Department of Chemistry Indian Institute of Science Education and Research (IISER) Tirupati,
Tirupati-517507, India
E-mail: [email protected]; [email protected]
Personel webpage: https://sites.google.com/view/balaramansresearchgroup/home
70
Bronze Medal Lectures
Non-noble metal catalysis: Applications in dehydrogenation and related reactions
Ekambaram Balaraman*
Department of Chemistry Indian Institute of Science Education and Research (IISER) Tirupati, Tirupati – 517507, India.
Catalytic dehydrogenation is one of the most fundamental processes in synthetic chemistry and
chemical biology. Recently, acceptorless dehydrogenative coupling (ADC) and hydrogen-atom (HA)
transfer reactions of renewable chemical feedstocks with the liberation of molecular hydrogen/water
open a new avenue in contemporary organic synthesis and have manifold practical applications in
sustainable energy.[1]
Despite significant advances achieved in noble-metal catalysis, the limited
terrestrial abundance, and the high cost and high-degree price fluctuation of precious-metal catalysts
and the supporting ligands have prompted chemists and chemical industrialists to search for new
sustainable catalysts to facilitate practical applications. Thus, the replacement of noble metals with
base metals for similar or better reactivity is one of the promising approaches in homogeneous
catalysis. However, the search for an efficient catalytic system based on base-metal catalysts for
sustainable chemical transformations is extremely rare.[2]
We have successfully designed and
prepared a new cheap-metal based catalysts (Mn, Fe, Co, Ni) and applied in various synthetic
transformations.[3]
Herein, some of our recent progress on acceptorless dehydrogenation and related
reactions using cobalt, and nickel complexes will be discussed.
References:
1. (a) A. Nandakumar, S. P. Midya, V. G. Landge, E. Balaraman, Angew. Chem. Intl. Ed., 2015,
54, 11022 (Minireview). (b) E. Balaraman, A. Nandakumar, G. Jaiswal, M. K. Sahoo, Catal.
Sci. Technol., 2017, 7, 3177.
2. (a) G. Jaiswal, V. G. Landge, D. Jegadeesan, E. Balaraman, Nature Commun., 2017, 8, 2147.
(b) S. P. Midya, V. G. Landge, M. K. Sahoo, J. Rana, E. Balaraman, Chem Commun., 2018,
54, 90. (c) V. G. Landge, A. Mondal, V. Kumar, A. Nandakumar, E. Balaraman. Org. Biomol.
Chem., 2018, 16, 8175. (d) A. Mondal, M. Subaramanian, A. Nandakumar, E. Balaraman.
Org. Lett., 2018, 20, 3381. (e) J. Rana, R. Babu, M. Subaramanian and E. Balaraman. Org.
Chem. Front., 2018, 5, 3250. (f) V. G. Landge, V. Yadav, M. Subaramanian, P. Dangarh, E.
Balaraman. Chem. Commun., 2019, 55, 6130.
71
Gouriprasanna Roy
Department of Chemistry Indian Institute of Technology Tirupati (IIT Tirupati), Tirupati, AP – 517 506 E-mail: [email protected]
Education PhD, 2007 - Department of Inorganic and Physical Chemistry (IPC), Indian Institute of Science (IISc),
Bangalore, India. Advisor: Prof. G. Mugesh MSc, 2002 - Chemistry, University of Calcutta, Kolkata, India. Professional Experience
Jan 2020 – Present July 2018 – Jan2020 November 2012 -June 2018 November 2011 – September 2012 January 2008 – November 2011 June 2007 – December 2007
Associate Professor, Department of Chemistry, Indian Institute of Technology Tirupati (IIT-Tirupati), Tirupati, A.P – 517 506. Associate Professor, Department of Chemistry, Shiv Nadar University (SNU), Greater Noida, Gautam Budh Nagar, UP-201 314. Assistant Professor, Department of Chemistry, SNU, Greater Noida, UP-201 314. Research Associate, Department of Chemistry, The Scripps Research Institute, San Diego, USA. Post-doctoral Fellow in Chemical Biology program, Department of Physiology and Pharmacology, Oregon Health and Science University (OHSU). Oregon, USA. Research Associate, Department of Inorganic and Physical Chemistry, Indian Institute of Science (IISc), Bangalore, India.
72
Bronze Medal Lectures
Biomimetic Studies to understand the mechanism of Hg−C bond protonolysis by
mercury-resistant Organomercurial Lyase MerB
Gouriprasanna Roy
Department of Chemistry Indian Institute of Technology Tirupati (IIT Tirupati), Tirupati, AP – 517 506
Methyl mercury (MeHg+
) is a ubiquitous environmental pollutant and a potent neurotoxin. It accumulates at high
levels in food chains, mainly in fish and seafood, and therefore, consumption of these contaminated foods
poses a significant risk to human health.1
On the other hand, exposure to ethyl mercury (EtHg+
) is an another
serious concern in developing countries where EtHg+
-containing antimicrobial agent ―Thimerosal‖ is commonly
used as a preservative in multiuse vials of vaccines and in other medicines.2
In nature, however, several
microorganisms have been reported to detoxify organomercurials including MeHg+
by converting them to
less toxic biologically inert species. For instance, bacterial organomercurial lyase (MerB) catalyzes the
protolytic cleavage of the otherwise inert Hg C bond of MeHg+
and produces methane (CH4) gas and ionic
mercury Hg2+
, while a second enzyme mercuric ion reductase (MerA) reduces the product Hg2+
to volatile Hg0
.
On the other hand, several sulfate reducing bacteria (SRB) convert highly toxic MeHg+
to less toxic
insoluble HgS(s) (metacinnabar) by producing H2S during metabolism.3
In fact, insoluble mercury selenide
(HgSe) have been detected in various tissues of marine mammals and also detected in different organs
(kidney, liver, muscle, and brain) of humans exposed to MeHg+
. Inorganic HgSe is considered to be much less
toxic than the mobile, water-soluble MeHg+
species including MeHgCys and MeHgSG. In this talk, I will
mainly focus on how small synthetic molecules can be used intelligently to detoxify toxic organomercurials in
various pathways, similar to those observed in nature.4,5
References:
1. Clarkson, T. W.; L Magos Crit. Rev. Toxicol. 2006,36, 609–662.
2. Geier, D. A.; King, P. G.; Hooker, B. S.; Dórea, J. G.; Kern, J. K.; Sykes, L. K.; Geier, M.
R. Chimica Acta 2015, 444, 212–220.
3. Omichinski, J. G. et al. J. Biol. Chem. 2009, 284, 938–944.
4. (a) Roy, G. et al. Angew. Chem., 2015, 127, 9455–9459; Angew. Chem. Int. Ed., 2015, 54, 9323–
9327; (b) Roy, G. et al. Chem. Eur. J, 2017, 23, 5696–5707; (c) Roy, G. et al. Inorg. Chem. 2017,
56, 12739–12750. (d) Roy, G. et al. Inorg. Chem. 2017, 56, 12102–12115. (e) International
Patent filed (PCT): WO2017168451.
5. Roy, G. et al. Chem. Comm. 2020, xx, xxxx.
73
Santanu Kumar Pal
Department of Chemical Sciences,
Indian Institute of Science Education and Research (IISER) Mohali,
Sector-81, Sahibzada Ajit Singh Nagar, Knowledge City,
Manauli 140306, India
E-mail: [email protected]
Santanu Obtained his B. Sc. from Ramakrishna Mission Vidyamandira, Belur (2001) and M.Sc. from
University of Calcutta (2003). After completing his doctoral studies in 2008 at Raman Research
Institute, Bangalore, he worked as a postdoctoral fellow at University of Wisconsin-Madison, USA
(2008-2010). In 2010, he returned to India to join Indian Institute of Science Education and Research,
Mohali as an Assistant Professor and was promoted to Associate Professor in 2016. His research
interest‘s primary revolve around Supramolecular Chemistry in particular, discotic liquid crystals in
Organic electronic devices and Biological Sensing using soft and Active matters. He has published
more than 100 publications in reputed peer reviewed international journals. Santanu is a recipient of
the Indian National Science Academy (INSA) Medal for Young Scientists (2015), the National
Academy of Sciences, India (NASI)-Young Scientist Platinum Jubilee Award (2015), DST-Young
Scientist Award (2012) and DAE Young Achiever Award (2014) from BOARD OF RESEARCH IN
NUCLEAR SCIENCES (BRNS), INDIA. He has been chosen to receive The CRSI Bronze Medal
(2020) in recognition of his contributions to research in Chemistry from Chemical Research Society of
India.
74
Bronze Medal Lectures
Highly Efficient Ambipolar Charge Transport in Semiconducting Discotic Liquid Crystals Santanu Kumar Pal*
Department of Chemical Sciences, Indian Institute of Science Education and Research (IISER)
Mohali, Sector-81, Sahibzada Ajit Singh Nagar, Knowledge City, Manauli 140306, India
The hunt for condign ambipolar charge transport materials remains a significant challenge over the
past few years. To achieve such demand, intensive efforts are being made using organic
semiconductors that carries high electrical performance as well as can be easily processed using
different solution processing techniques. However, the crucial challenge is to find a subtle balance
between the mobility and processability of these materials. For example, single crystals, known for
high mobilities, suffer from inherent fragility and flexibility, which limit their usability in devices.
Similarly, in polymeric systems, inadequate solubility, low purity, and structural and energetic disorder
have curbed their charge transport properties. To overcome these challenges, recent research has
focused on organic small molecules, which offer solution-processed, defect-free films along with high
chemical purity. In this context, discotic liquid crystals (DLCs) comprising a central rigid aromatic core
substituted with a mantle offer flexible alkyl chains, are currently in the spotlight of material scientists.
This talk will unmask a unique ability of Heterocoronene1 based DLCs and others
2 to serve as highly
efficient ambipolar charge carrier transporting organic semiconductor when used in Space Charge
Limited Current (SCLC) devices. These bipolar transport materials would be highly cost-effective due
to incorporation of a single layer of organic materials in device architecture. Our results are
comparable with the best amorphous as well as polycrystalline organic semiconductors reported till
date.
References:
1. De, J.; Bala, I.; Gupta, S. P.; Pandey, U. K. Pal, S. K.* J. Am. Chem. Soc. 2019, 141, 18799-
18805.
2. Bala, I.; Yang, W. Y.; Gupta, S. P.; De, J.; Yadav, R. A. K.; Singh, D. P.; Dubey, D. K.; Jou, J.
H.; Douali, R.; Pal, S. K.* J. Mater. Chem. C. 2019, 7, 5724-5738.
75
26th
CRSI National Symposium in Chemistry
Invited Lectures
76
R. Vijayaraghavan
Professor Department of Chemistry, School of Advanced Science, VIT, Vellore, 632 014 Email: [email protected]
Rajagopalan Vijayaraghavan studied his Undergraduate and Master’s at University of
Madras, Chennai and Doctor of Philosophy at Indian Institute of Science, Bangalore . He
then pursued his post doctoral research at ISMRA- CRISMAT, Caen, France, ICMAB-
Barcelona Spain, IIT Madras for about 7 years. He joined with VIT in 2002 and continued his
area of research on Inorganic Solid State Materials related to Energy and Environment as
well biomedical. He has been a visiting Scientist at Nagoya University Japan, Inorganic
Chemistry Laboratory, Oxford University (Commonwealth fellow), UK and RMIT & University
of Melbourne, Australia, JNCASR Bangalore. During his stay in UK as a Commonwealth
Fellow, he was selected as a distinguished foreign fellow He has been awarded with
Materials Research Society of India (MRSI) medal and Solid State chemistry medal. He is
passionate about what he is doing. His hobbies are chess, music and tennis.
77
Invited Lectures
Development of Sensors & Prototype Set up for Fruit Ripening Applications
R. Vijayaraghavan
Department of Chemistry, School of Advanced Science, VIT, Vellore, 632 014
Fruits while ripening release ethylene, in general, through bio synthesis in ppm level. The amount of
ethylene released is an indicator on the state of fruit ripening and hence the measurement of ethylene
is of importance during the post-harvest of the fruits and also during transportation of the fruits, in
order to avoid over ripenin. However, a concentration as low as 1 ppm of ethylene exposed in the fruit
ripening environment is sufficient to promote the fruit ripening process. Artificial ripening agents
(calcium carbide) trigger ripening process in apple, avocado, banana, mango, papaya, pineapple and
guava. Therefore, the fruits can be sold before the predicted natural ripening time for making more
profit. Artificially ripened fruits cause health hazards to consumers .There is a need to differentiate
natural and artificial fruit ripening effectively on site for societal benefit in order to suppress the latter,
Towards this objective, we have developed MWCNT based chemical sensor and IR absorption based
physical sensor & Lab based proto types to detect and estimate ethylene. It is interesting to note that
the rate of release of ethylene during artificial ripening is much faster& higher than the natural one.
Our methods have better performance in terms of sensitivity. novelty of the sensor element and could
differentiate the process effectively.
Ethylene release in natural and artificial fruit ripening by our MWCNT sensor
References:
1. J. Kathirvelan, R. Vijayaraghavan, J. Sensors, 2014, 39505-09,
2. J. Kathirvelan, R. Vijayaraghavan, Infrared. Phy. Tech., 2017, 85, 403-409.
3. J. Kathirvelan R. Vijayaraghavan Review Article, Sens. Rev. 2020 ( accepted).
78
Hongdoo Kim Professor Department of Advanced Materials Engineering for Information & Electronics, Kyung Hee University, Yongin, Gyeonggido 17104, Korea Email: [email protected]
Hongdoo Kim was awarded his Ph.D degree in Physical Chemistry from Univ. of Wisconsin-Madison,
Wisconsin, U.S.A in the year 1987. He did his post doc from the University Wisconsin-Madison and
NIST, Gaithersberg, MD. Currently he is working as full Professor in Kyung Hee University. He has
published 61 publications, 12 Korean Patents, 3 US Patents. Currently he is having 3 ongoing National
Projects.
79
Invited Lectures
HYBRID PIEZOCAPACITIVE/PIEZOELECTRIC SENSOR BASED ON ELECTROSPUN
NANOFIBER WEBS
Mohammad Shamim Reza
1, Arun Anand Prabu
2, Hongdoo Kim*
1,2
1 Department of Advanced Materials Engineering for Information & Electronics,
Kyung Hee University, Yongin, Gyeonggido 17104, Korea 2 Department of Chemistry, School of Advanced Science, VIT, Vellore 632014, Tamil Nadu, India
Recently, polymer-based flexible tactile/pressure sensors have attracted widespread interest among
researchers and technologists working in soft robotics, wearable and/or health monitoring devices,
etc. In our previous study, a piezo-capacitive sensor based on electrospun polyurethane (PU)
nanofiber having very high amount of nano-sized open cells was used for monitoring both static and
dynamic pressures [1]. In another study, electrospun polylactic acid (PLA) exhibited high shear-
piezoelectricity due to its inherent helix orientation and preferential aligning of C=O functional groups
under applied DC voltage [2]. In this study, we attempted coaxial electrospinning of PU-PLA under
controlled conditions to obtain core-shell (PLA-PU) structured nanofiber web, and electrospinning of
PU-PVDF blend solution to investigate their physico-mechanical and piezo-responsive behaviors. The
piezocapacitive/piezoelectric hybrid sensors are capable of simultaneously measuring
piezocapacitance as well as piezoelectricity by applying pressure using LCR meter, Dynamic tester
and Piezo Film Amplifier. The piezoelectric signals are strongly dependent on the ratio of piezoelectric
part and piezocapacive part under external pressure, whereas piezo capacitance under applied
pressure linearly increases with decreasing thickness of the nanoweb due to the rubbery PU shell part
[3,4]. Moreover, PU-PLA nanoweb based on stacking hybrid was also fabricated and investigated for
their piezo-responsive characteristics.
Figure. Time vs voltage signal curves for (a) neat PLA and (b) PU-PLA (shell/core, 55/45 (w/w)).
Single cycle load vs capacitance hysteresis curves for (c) neat PU, (d) neat PLA and (e) PU-PLA
(shell/core, 55/45 (w/w)) nanoweb-based sensors under external pressure.
References
1. M.S. Reza, K.R. Ayag, M.K. Yoo, K.J. Kim, H. Kim, Fiber. Polym., 20(2), 337-347 (2019).
2. S. J. Lee, A. A. Prabu, K. J. Kim, Mater. Lett., 148, 58-62 (2015).
3. R.T. Selvan, Y. J. Ahn, K. J. Kim, H. Kim, Fiber. Polym., 18, 1898-1905 (2017).
4. E. S. Guerra and E.V. Lima, Handbook of Polymer Synthesis, Characterization, and Processing,
53 (2013).
80
Annamalai Senthil Kumar
Nano and Bio-electrochemistry Research Laboratory, Department of Chemistry, School of Advanced Sciences and CO2 Research and Green Technology Centre, Vellore Institute of Technology University, Vellore-632 014, India
A. Senthil Kumar is a Senior Professor in Carbon dioxide Research and Green Technology Centre of
Vellore Institute of Technology University, India. He obtained his Ph.D degree in department of
Physical chemistry, University of Madras, India in 2000. He was a postdoctoral fellow in Prof. J.-M.
Zen‘s laboratory, National Chung Hsing University, Taiwan for about 7 years (1998-2005) and as a
Japan Society for the Promotion of Science (JSPS) fellow with Prof. Tanase, Nara Women‘s
University, Japan for 2 years (2005-2007). He has published over 151 international peer-reviewed
journals (on 29th Nov 17) and having the Scopus h-index value 29 (on 29th July' 17). His research
interest includes interdisciplinary areas of material science, physical & analytical chemistry in
particular of designing and application of nanostructured chemically modified electrodes,
encapsulation of organic and pharmaceutical molecules within carbon nanotubes, electrocatalysis,
nanoparticles and chemical & biosensors.
81
Invited Lectures Redox Active Organic Molecule Functionalized Carbon Nanomaterials for Elegant
Electrochemical Immuno-sensing of Shrimp-Virus
Annamalai Senthil Kumar
Nano and Bio-electrochemistry Research Laboratory, Department of Chemistry School of Advanced Sciences and CO2 Research and Green Technology Centre, Vellore Institute of Technology University, Vellore-632 014, India
White spot syndrome virus (WSSV), a new
family of viruses named Nimaviridae, genus
Whispovirus, is a highly lethal, contagious
and the most serious viral pathogen to
penaeid shrimp. It causes 100% mortality
within 3–7 days of attack. Since the first
outbreak in Taiwan in 19923, WSSV has
been spreading worldwide and resulting in
huge economic loss in the shrimp
aquaculture industries. In India, the gross economic loss due the WSSV attack was estimated as
48717 metric-ton of shrimp, which is equivalent to USD 150 million and employment of 2.15 million
man days. WSSV disseminates quickly under normal environmental condition and infects a wide host
range of host which includes copepods, crab, lobster, cray-fish and prawn. Our group has developed
a simple and selective electrochemical immunosensor based on methylene blue or hydroquinone
derivative immobilized carbon nanomaterial modified electrodes for WSSV in raw infected shrimp
tissue samples.1,2
Note that there are some conventional analytical techniques available for WSSV
detection are based on polymerase chain reaction (PCR), DNA microarray, dot blot, western blot,
enzyme linked immunosorbent assay (ELISA), affinity immunosensor, and antibody based microarray
methods. Unfortunately, all these molecular techniques have their own limitations such as less
sensitivity and high detection limit (~103 copies of its gene μ L−1), complicated offline preparation
procedures, involvement of carcinogenic chemicals like ethidium bromide (in polymerase chain
reaction (PCR)), requirement for well-equipped laboratories (for DNA assays), trained technicians and
time consuming measurements (For ELISA 2–3 days‘ of time period required). This presentation
covers preparation, characterization and shrimp-virus electrochemical immunosensor application.
References: 1. A.Natarajan, K.S.Shalini Devi, S.Raja and A.S. Kumar, Scientific Reports, 2017, 7:46169
2. M.Gandhi, D.Rajagopal, S.Parthasarathy, S.Raja, S.-T.Huang, A.Senthil Kumar, ACS Omega
2018, 3, 10823−10835.
82
Sellappan Senthilkumar
Associate Professor Department of Chemistry School of Advanced Sciences Vellore Institute of Technology (VIT) Vellore – 632014, INDIA.
S. Senthil Kumar was awarded his Ph.D. in Analytical Chemistry from University of Madras in the year
of 2009. He did his post-doctoral research from Yonsei University, Seoul, South Korea in the year
2010-12 under the supervision of Prof. Dongil Lee. Currently he is working in VIT – Vellore as an
Associate Professor. He is a fellow of the Academy of Sciences Chennai, since 2019. He has
completed 3 funded projects like CSIR, SERB and DBT. She has published 35 reputed international
journals including ACS Nano, Analytical Chemistry, Biosensors and Bioelectronics, Nanoscale and
Scientific Reports.
83
Invited Lectures Rationally Designed Ionic Liquids for Electrochemical Sensing Sellappan Senthilkumar
Department of Chemistry, School of Advanced Sciences,
Vellore Institute of Technology (VIT), Vellore-632014, India.
The rational design of materials and molecules with well-defined properties is a compelling need for
realizing their industrial and technological applications. Ionic liquids have attracted a great deal of
attention as environmentally benign media owing to the deck of properties extremely low vapour
pressure, a wide liquid range, low flammability, high electrical conductivity, good solvent properties for
a wide variety of compounds, high thermal stability, and a large electrochemical window that make it
possible to use them in several applications including lower melting points, wide range of solubility,
negligible vapour pressure, tunable miscibility and viscosity.1 These ILs comprising organic cations
and inorganic anions offers plethora of combinations that can be tuned to achieve desired
physicochemical properties for specific application. This tunability of ILs has rendered remarkable
characteristics such as high ionic conductivity, non-flammability, biocompatibility and good
electrochemical and thermal stability, which are desired for electrochemical applications. Accordingly,
ILs have attracted worldwide recognition and opened the avenues for their application in biosensor,
biomedical, biocatalysis and bioelectronics. In this talk, some of our recent attempts to design few IL
molecules for the development of electrochemical sensors/biosensors will be presented. To begin
with, we have synthesized IL molecules containing redox moieties and utilized them in both enzymatic
and non-enzymatic biosensing.2 Further, we have synthesized functionalized ILs and employed these
molecules as versatile platforms for the immobilization of biomolecules, followed by electrochemical
biosensing. Our recent interest on tuning these ILs and exploring their applications in other areas of
electrochemistry will also be discussed.
References:
1. Ghorbanizamani, F.; Timur, S., Anal. Chem. 2018, 90, 640-648.
2. Manoj, D.; Theyagarajan, K.; Saravanakumar, D.; Senthilkumar, S and Thenmozhi, K.;
Biosens. Bioelectron. 2018, 103, 104–112.
84
S.K. ASHOK KUMAR
Associate Professor Department of Chemistry School of Advanced Sciences Vellore Institute of Technology Vellore-632014, Tamil Nadu, India E-mail: [email protected]
S. K. Ashok Kumar has awarded his PhD degree from Thapar University, Patiala, Punjab in the year
2006. His expertise is in Chemical Sensors (chromogenic, fluorogenic, potentiometric and
voltammetric), Inorganic ion-exchange material (separation, ion sensing, and catalysis) and
Nanocomposites and Porous carbon materials for water applications. He is a member of various
professional Society like Life membership of chemical research society of India (LM 1277), Life
membership of Indian Society for Electroanalytical Chemistry (ISEAC), Mumbai Dona Paulia, Goa
and Life membership of Indian Science Congress, Kolkata. He has published more than 65
international journals, 1 review and 1 book chapter. He has completed 5 funded projects also.
85
Invited Lectures
New Thorium (IV) Selective Sensors
S.K. Ashok Kumar
Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore-632014, Tamil Nadu
Thorium is an important metal for diverse applications such as manufacture of ceramics, carbon arc
lamps, and catalyst in the chemical industry. It is also used as nuclear reactor fuels in the near future.
Due to an extensive use of Th, contamination of air, water and soil components are likely. The UV-
visible spectrophotometry, spectroflurometriy and potentiometric techniques are widely used due to its
advantages such as cost-effectiveness, rapid detection, real-time monitoring, and ease of operation.
Therefore, the sensing materials which are easy to synthesize and apply for a real-time monitoring of
thorium in actual samples is the need of the hour. In this presentation, three different sensing
materials such as N',N'-bis(-(2-hydroxynaphthalen-1-yl)methylene)-1,10-phenanthroline-2,9-
dicarbohydrazide (S1), dibutyl (2-oxo-2-(quinolin-8-ylamino)ethyl) phosphinate (S2) and dibutyl (8-
hydroxyquinolin-2-yl) methyl phosphonate (S3) developed as chromogenic, fluorogenic optode and
potentiometric sensor for Th4+
ions. The lowest detection limit of Th (IV) by S1, S2 and S3 sensors
were found to be 50 nM, 1.1 nM and 1.2 ppm respectively. All three sensors were successfully
applied to estimate the Th4+
in real time samples such as monazite sand and gas mantles samples.
The binding mechanism of sensing material with Th4+
ions was studied by 1H NMR, ESI-mass
analysis and theoretical calculations.
S1 S2 S3
References:
1. Selva Kumar, R., Ashok Kumar, S. K., Vijayakrishna, K., Sivaramakrishna, A.,
Brahmmananda Rao, C. V.S., Sivaraman, N. and Sahoo, S. K. Inorganic Chemistry 2018, 57,
15270-15279.
2. Selva Kumar, R., Ashok Kumar, S. K., Vijayakrishna, K., Sivaramakrishna, A.,
Brahmmananda Rao, C.V.S., Sivaraman, N. and Sahoo, S. K. Analytical Methods 2018, 11,
1338-1345
3. Selva Kumar, R., and Ashok Kumar, S. K. Dalton Trans., 2019, 48, 12607-12614.
86
S. Sarveswari
Professor Department of Chemistry School of Advanced Sciences Vellore Institute of Technology Vellore-632014, Tamil Nadu, India S. SARVESWARI is working as a Professor in the Department of Chemistry, School of Advanced
Sciences, VIT-Vellore. He has completed the Doctoral degree from VIT-Vellore in the year of 2010.
He has published more than 130 articles in various Scopus indexed International journals and
published 3 monographs also. He has given 5 Ph.D degree and currently six students are pursuing
their Ph.D under her supervision. She is serving as reviewer in more than 20 international journals
and in couple of journals as editorial board member also.
87
Invited Lectures
Organic Small Molecules as Chemosensors
S. Sarveswari*
Department of chemistry, School of Advanced science, VIT-Vellore
Design and development of molecular probes for anion and cation recognition is an interesting topic
of research till date. The organic small molecules found to serve as a chemo sensors. We are
concentrating on cyanide, fluoride ion and mercury sensing. Mercury is one of the more toxic
transition metal ions, which is a non-biodegradable environmental pollutant. It shows adverse effects
on human health as well as living beings while consumed unknowingly. Generally mercury available
in pollutants as oxidized form (Hg2+
),element state (Hg0) and organic form methyl mercury (MeHg).
Among this methylmercury can cause chronic diseases like central nervous system damages, brain,
kidney, and liver damage. Similarly cyanide also associated with toxic effects. Absorption of cyanide,
lead to various types of physiological disorders like convulsions, loss of consciousness and eventually
death. Due to the serious health hazards associated with cyanide ion and mercury pollutants, we
made an attempt to develop probes for the detection of them. Here in some simple organic molecules
found confer this sensing property will be discussed.
Figure 1 Efficient sensing of pyrazole and diaminodicyano malononitrile derivatives
References:
1. Sarveswari, S; Jesin Beneto. A; Siva, A Sens. Actuators B Chem 2017, 245, 428-434.
2. Karuppusamy, P; Senthilvelan, J; Vijayakumar,V; Sarveswari, S Chemistry select 2020, 5, 49-53.
88
Abstracts: Posters
93
P1: Synthesis, Characterisation and Nucleic acid Interactions of Phenanthroline Derivatives for
Cytotoxicity Studies
Sourav De1, Selva Kumar R
1, S K Ashok Kumar
1*, Anbalagan Moorthy
2
1Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore
632014, India 2Department of Bio Sciences and Technology, Vellore Institute of Technology, Vellore-632014, India
In this poster presentation, reporting design and synthesize of phenanthroline analogues for
anticancer studies. Initially, the light absorbing and emission abilities of ligands and their binding
interaction with CT-DNA and protein binding interaction were studied by using absorption and
emission techniques respectively. It reveals that a strong absorption peak appeared around at 270 nm
due to π-π* transitions of the phenanthroline moiety. The binding constant of ligands with DNA was
found to be 104-10
5 M
-1. The
competitive displacement of ethidium bromide from DNA in the presence
of ligand study reveals that ligand exhibits an efficient binding affinity (KSV=104 M
-1 and Kapp=10
6 M
-1)
indicating intercalation or groove binding of the ligands with CT-DNA which is further supported by
viscosity studies. The gel electrophoresis analysis show that selected ligand (Phen-Hy) destroys
plasmid DNA (10 kb) within 1.5 h of contact time due to intercalation mode. The MTT assay
performed using two different cancer cell lines (HeLa and MDA-MB-231) and compared with normal
HEK-293 cells. The obtained results reveals that Phen-Hy exhibits high potency and selectivity
cytotoxicity profiles in both the cell lines.
Scheme 1: MTT cytotoxicity screening of phenanthroline ligand
References
1. Selvakumar, R.; Ashok Kumar, S. K.; Vijayakrishna, K.; Sivaramakrishna, A.; Brahmmananda
Rao, C. V. S.; Sivaraman, N.; Sahoo, S. K.. Inorg. Chem. 2018, 57, 15270.
2. Siddiqui, S. A.; Potewar, T. M.; Lahoti, R. J.; Srinivasan, K. V.. Synthesis (Stuttg). 2006, 2006
(17), 2849–2854.
3. Siddiqui, S. A.; Narkhede, U. C.; Palimkar, S. S.; Daniel, T.; Lahoti, R. J.; Srinivasan, K. V.
Tetrahedron 2005, 61, 3539–3546.
94
P2: Fluorescent Dipyrromethane Analogues as Potent Photoinduced Biosensors
Shiva Krishna Loke, Eswar Pagadala, Ravi Kumar Kottalanka*
Division of Chemistry, Department of Sciences and Humanities, VFSTR (Deemed to be University),
Vadlamudi, Andhra Pradesh-522213, India
Recent times, fluorescence chemistry particularly, fluorescence imaging and indicators are essential
tools in various fields of modern science and medicine, including clinical diagnostics, biotechnology,
molecular biology and biochemistry, materials science, and analytical and environmental chemistry.1
Fluorescence materials have numerous applications such as information displays, memories,
sensors, probes and photo-modulation.2 The fluorescence properties of chemical substrates indeed
depend on the structure of their molecular assemblies. The simple structural and conformational
changes play a major role in the precise analysis of biological functions and several biochemical
reactions.3 However, certain molecular systems change their chemical structure and behaviour in
response to external support such as chemical, electrical and light thereby modulating fluorescence
properties. In particular, the photoinduced proton transfer (PPT) in dipyrromethane analogues such
as photoenolization and phototautomerization are being special interest, since they were evolved as
potent photoinduced biosensor capable of showing “fluorescence on” property at excited state via
double proton transfer mechanism.4 In this context we synthesised three new dipyrromethane
analogues i.e. [(Ph)(CH3)C{C4H2NH(CHO)}2] (DAA), [(Ph2)C{C4H2NH(CHO)}2] (DAB) and
[(Ph)(CH3)C(Ph3C-N=CH-C4H2NH)2] (DIDPM) in good yield (90%) via Vilsmeier-Haack and Schiff
condensation method respectively. The systematic study of absorption, emission and lifetime of decay
process by photoirradiation methods showed promising results. All the compounds were exhibiting
large, Stokes shifted emissions at different wavelengths with good lifetime measurements in different
solvents. Further, all the compounds were characterized by IR, 1H NMR,
13C NMR spectroscopy and
DAA moiety was confirmed by single crystal X-ray diffraction analysis.
References:
1. N. Boens, V. Leen and W. Dehaen., Chem. Soc. Rev., 2012, 41, 1130–1172.
2. G. Mayer and A. Heckel, Angew. Chem.,Int. Ed., 2006, 45, 4900.
3. T. Kobayashi, T. Komatsu, M. Kamiya, C. Campos, M. Gonza´lez-Gaita´n, T. Terai, K.
Hanaoka, T. Nagano and Y. Urano, J. Am. Chem. Soc., 2012, 134, 11153.
4. K. C. G. Sreedevi, A.P. Thomas, K. H. Aparna, R. Pradhan, M. L. P. Reddy, U. Lourderaj
and A. Srinivasan., Chem. Commun., 2014, 50, 8667.
95
P3: Catalytic activity of the Gallium Metal Complexes Towards Ring-opening Polymerization of
Cyclic Esters like ɛ-Caprolactone & Ethylene Brassylate
Eswar Pagadala, Shiva Krishna Loke , Ravi K. Kottalanka*
Department of Sciences and Humanities, Division of Chemistry, VFSTR (Deemed to be University),
Guntur, Andhra Pradesh- 522 213, India.
The ring-opening polymerization (ROP) of cyclic esters like ɛ-Caprolactone & 1,4-
Dioxacycloheptadecane-5,17-dione (ethylene brassylate) by discrete organic/inorganic initiators has
been intensively investigated over the past 10 to 15 years1. Over the past five years, Ga (III) have
attracted a growing interest towards ROP of cyclic esters, like ɛ-Caprolactone. Motivated by these
results we successfully established highly potential Gallium metal complexes [(L1)2Ga-N(SiMe3)2](1)&
[(L1)2Ga (TBD)](2) (where L1=[Ph3CN=CH-C4H3NH] via one-pot slat metathesis route & ligand group
exchange reactions under inert atmospheric conditions at ambient temperature. All these complexes
were initially characterized by using spectroscopic and analytical techniques. The crystal structure of
Gallium complex (1) was further confirmed by single crystal X-ray diffraction analysis. The ring-
opening polymerization of ɛ-Caprolactone and ethylene brassylate was studied under various
conditions and obtained polymers were characterized by using NMR analysis.
References:
1. Samuel Dagornea, Mickael Normand, Evgeny Kirillov, Jean-Francois Carpentier, Coordination
Chemistry Reviews 2013, 257, 1869.
2. Pallabita Basu, Robi Sikdar, Tarun Kumar and Irishi N N Namboothiri. J. Euro Polymer. 2018,
108, 380.
96
P4: Structurally tuned Pd-Cu Systems as Efficient Catalysts for Ethanol Oxidation Reaction
P. C. Ashly1,2
, Shreya Sarkar2,3
, Sebastian C. Peter2,3*
1Department of Chemistry, St. Joseph’s College, 36, Lalbagh Road, Bangalore 560027, India
2New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Bangalore 560064,
India.
3School of Advanced Materials, Jawaharlal Nehru Centre for Advanced Scientific Research,
Bangalore 560064, India.
The manipulation of the structural ordering in nanomaterial compounds are of great interest in tuning
the surface properties with enhanced activity and selectivity towards various important catalytic
processes. On another note, development of highly active and stable low cost Pt-free catalysts for
ethanol electro-oxidation (EOR) in alkaline medium has drawn a lot of attention in recent years.
Palladium based catalysts are on the forefront of this research. In this work, we have manipulated
synthetic strategies for the formation of PdCu nanoparticles in various structural forms ranging from
bimetallics, alloy and intermetallics, which in fact controlled the ordered-disordered arrangement of Pd
and Cu atoms. The Pd-Cu catalysts with different chemical compositions were attempted by
solvothermal method using NaBH4 as a reducing agent and were well characterized by XRD, XPS,
ICP-OES, TEM and XAFS. The effect of different metal concentrations also utilized for the formation
of heterostructures Cu/PdxCu1-x, PdxCu1-x/PdCu, Pd/PdxCu1-x and Pd/PdCu. The powder XRD and
XAFS techniques were efficiently utilized to characterize these heterostructure models. The PdCu
nanocatalyst with ordered structure (CsCl type) showed excellent catalytic activity compared to
PdxCu1-x alloy (Cu type) nanoparticles and heterostructures. The atomic ordering Pd and Cu in the
PdCu intermetallic was the driving force for the enhancement in the catalytic activity with high mass
activity (418.5 mA/mg Pd) compared to the other systems.
References:
1. Sarkar, S.; Jana,R.; Suchitra; Waghmare, U. V.; Kuppan, B.; Sampath, S.; Peter, S. C.
Chem. Mater. 2015, 27, 7459.
2. Marakatti, V. S.; Sarma, S. Ch.; Joseph, B.; Banerjee, D.; Peter, S. C. ACS Appl. Mater.
Interfaces. 2017, 9, 3602.
97
P5: Fluorescence Modulation on Imidazole-Tethered Anthracene Derivatives by Aromatic
Acids
Munendra Pal Singh, Jubaraj B. Baruah*.
Chemistry Department. Indian Institute of Technology, Guwahati 781039, India.
Fluorescent molecules attached to chain containing multiple donor sites are conventionally used in
molecular switches. Di-topic molecule that has two or more protonation sites as illustrated in Fig. 1a
has scope to modulate emission properties by varieties of ways by stimulates. The example shown
with an anthracene fluorophore will also be suitable for π- stacks among themselves or stacks with
other π-systems adding extra feature to modulate emission properties. As a quest for such examples,
we synthesized a di-topic compound 9-N-(3-imidazolylpropylamino) methylanthracene (HL). This
compound has possibility to form salts at different proportions of weak acids such as nitro-phenols.
We studied salts of nitro-phenols and carboxylic acids listed in the Fig. 1a. After differentiating the
structures, we had studied their photo-physical properties in solid and solution states. An illustrative
example where distinguishable ON-OFF Emissions feature is observed is shown in Figure 1b.
(a) (b)
Figure 1: (a) A model receptor A to modulate fluorescence, the structures of HL and the partner acidic
aromatic molecules and, (b) Emissions of HL on interactions with acidic aromatic molecules.
The fluorescence changes observed from solid-samples and in solution studies are correlated through
analysis of data from quantum yields, life-time measurements.
Reference :
1. Singh, M. P.; Tarai, A.; Baruah, J. B. CrystEngComm. 2019, 21, 4898.
98
P6: Paper Based Self-assembled Tb3+
/Eu3+
Bis-lanthanide Ensemble: Probe for Differentiation
of Structurally Similar Norfloxacin and Ofloxacin
Ananya Biswas, Uday Maitra*
Department of Organic Chemistry, Indian Institute of Science, Bengaluru
Tuning the ratio of the peaks of two metallic probes in a hetero-bi metallic ensemble is an effective
way to read out the information about the chemical and environmental changes occurring in a system.
This ratio-metric measurement modulates the ratio of two emission peaks and eliminates impacts of
local probe concentration, sample environments, photo bleaching effects and power fluctuation of
photon sources by a self-calibration method. Herein, we report the first example of a supramolecular
self-assembled Tb3+
/Eu3+
bis-lanthanide ensemble (Scheme 1) in which the energy transfer process
from an antenna molecule (Norfloxacin or Ofloxacin ) to Tb3+
and Eu3+
takes place separately, along
with a simultaneous Tb3+
to Eu3+
energy transfer process. The relative contributions of Tb3+
and Eu3+
in the composite time-resolved luminescence spectrum can be modulated by changing the sensitizer
molecule. We have examined two structurally similar and frequently prescribed fluoroquinolone drugs,
Norfloxacin and Ofloxacin. These drugs are otherwise difficult to distinguish by conventional methods
(HPLC, UV or fluorescence) but can be differentiated by the designed Tb3+
/Eu3+
/cholate (4.5 mM/ 0.5
mM /15 mM) cocktail. The proposed bis-lanthanide cocktail in cholate (ch) gel matrix can be also
useful for concurrent determination of the ratio of their concentrations in a mixture.
Scheme 1: Scheme of representation for the detection and differentiation of NFLX and OFLX
References:
1. Raz, S. R.; Bremer, M. G. E. G.; Haasnoot, W.; Norde, W. Anal. Chem. 2009, 81 (18), 7743.
2. Bhowmik, S.; Banerjee, S.; Maitra, U. Chem. Commun., 2010, 46, 8642.
3. Yao, J.; Zhao, Y. W.; Zhang, X. M. ACS Omega. 2018, 3 (5), 5754–5760
99
P7: Selective turn-on pyridoxal based chemosensor for visual and fluorescent detection of
Zn(II) ion in DMF medium
K. A. Karthick, A. Tamilselvi*
PG & Research Department of Chemistry, Thiagarajar College, Madurai 625 009.
Zinc (Zn2+
) is present in all forms of life and is the second most abundant transition metal in the
human body after iron. Zn2+
is difficult to detect as it is spectrally silent.[1]
In the present study, we
have developed pyridoxal Schiff base ligand to selectively detect Zn2+
ions in the presence of various
other metal ions. Pyridoxal phosphate, the active form of vitamin B6, is a co-enzyme in a variety of
enzymatic reactions and its biological importance is well established. However, few reports on the
development of chemosensors utilizing pyridoxal platforms.[2]
Herein, we report synthesis of pyridoxal
based Schiff base (HL), namely, 4-((3-(cyclohexylamino)propylimino)methyl)-5-(hydroxymethyl)-2-
methylpyridin-3-ol and its selective recognition properties of Zn2+
. It exhibited rapid response and
unique selectivity of Zn2+
ion in DMF medium.The ligand (HL) and its corresponding zinc complex have
been synthesized and characterized by UV, FT-IR, NMR and ESI-MS technique. The optical and
fluorescence properties of HL were investigated in DMF solvent. The binding stoichiometry of HL with
Zn2+
and binding constant calculation will also be discussed. The ligand may give insight into the
design protocols required for the successful imaging of zinc ions.
HO
NHO
N
NHZn(II)
N
N
N
N
N
Zn2+
O
O OH
N
HO
Scheme 1. Sensing behavior of ligand (HL) towards Zn(II) ion.
References:
1. Nolan, E.M.; Lippard, S.J.; Acc. Chem. Res. 2009, 42, 193.
2. Thankaraj, A.; Ashok Kumar, S.K.; Suban, K.S.; Photochem. Photobiol. Sci. 2018, 17, 414.
100
P8: Synthesis of Carbazole Carboxylates and Angucycline-5-Aza Analogs via Hauser-Kraus
Annulation-Ring Expansion-Ring Contraction Methods
Chenikkayala Sivasankara, Irishi N. N. Namboothiri*
Department of Chemistry, Indian Institute of Technology Bombay, Mumbai 400076, India
The Hauser-Kraus annulation of sulfonylphthalide with N-protected 3-olefinic oxindole carboxylates
delivered the novel spiro-dihydronaphthoquinone-oxindoles.1
However, unprotected 3-olefinic
oxindoles afforded carbazole carboxylates via oxazepine intermediates in a cascade manner in one
pot. On the other hand, phenylethylidene oxindoles reacted with sulfonylphthalide to afford the
angucycline-5-aza analogs. The cascade approaches follow Hauser-Kraus reaction-ring expansion-
ring contraction methods to deliver the products in good to excellent yields.
Reference
1. Sivasankara, C.; Satham, L.; Namboothiri, I. N. N. J. Org. Chem. 2017, 82, 12939.
101
P9: TBHP/Cu(OAc)2 catalyzed oxidation of 4,5-dihydro-1H-pyrazoles: A Facile approach for the
preparation of 1H-pyrazoles
Kolla Sai Teja, Somanaboina Ramya, Bhimapaka China Raju*
Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India.
Pyrazoles are an important heterocyclic compounds and play an prominent role in organic synthesis
and medicinal chemistry.1 Celebrex, Viagra and Acomplia are important and commercially available
pyrazole drug molecules. Further, pyrazole derivatives have possess various biological properties
such as anti-tumor, anti-bacterial, anti-tubercular, anti-inflammatory, anti-diabetic, anti-depressant and
anti-malarial activities. Due to the importance of these compounds, method development necessary
for the preparation of pyrazoles. As a part of our ongoing research work on pyrazoles2-4
and synthesis
of novel heterocyclic cmpounds, a simple and efficient oxidative method has been developed for the
preparation of 1H-pyrazoles from 4,5-dihydro-1H-pyrazoles by using catalytic amount of
TBHP/Cu(OAc)2 as the catalyst (Scheme I). The method succesfully applied for the oxidation of
dihydro pyrazole heterocyclic compounds to pyrazoles.
Scheme I
References:
1. Fustero, S.; Rosello, M. S.; Barrio, P.; Fuentes, A S. Chem Rev. 2011, 111, 6984.
2. Hariprasad, K. S.; Prasad, K. V.; Raju, B. C. RSC Adv. 2016, 6, 108654.
3. Dayakar, Ch.; Jyothi, D; Suman, P.; Raju, B. C. Synth Commun. 2015, 45, 1642.
4. Saidachary, G.; Prasad, K. V.; Divya, D.; Singh, A.; Ramesh, U.; Sridhar, B.; Raju, B. C. Eur
J. Med Chem. 2014, 76, 460.
102
P10: Stereoselective Total Synthesis of (-)-Diaportinol, (-)-Desmethyldiaportinol, (-)-Diaportinic
acid and Peniisocoumarin
Aswathi Syam, Sunnappu Ranganayakulu, Rajendar Goreti *
School of Chemistry, IISER Thiruvananthapuram
We discuss about the total synthesis of (-)-Diaportinol (1), (-)-Desmethyldiaportinol (2), (-)-
Diaportinic acid (3) and Peniisocoumarin (4). Diaportinol, Desmethyldiaportinol and Diaportinic
acid were isolated from the cultures of Penicillium nalgiovense, which is ananamorph species of the
genus of Penicillium with lipolytic and proteolytic activity. These molecules reported to possess potent
cytotoxic activity. Peniisocoumarin was obtained from the fermentation of an endophytic fungus,
Penicillium commune QQF-3. Peniisocoumarin exhibits cytotoxicity and enzyme inhibitory activities
against α-glucosidase and Mycobacterium tuberculosis protein tyrosine phosphatase B (MptpB). For
the synthesis of these four naturally obtained bioactive molecules, we began our synthesis by chiral
pool strategy using commercially available D- malic acid.
Figure 1: Target molecules
References:
1. Cai, Runlin, et al. " Journal of natural products 81.6 (2018): 1376
2. Larsen, Thomas Ostenfeld, and Jens Breinholt. Journal of natural products 62.8 (1999): 1182.
3. Saeed, Aamer, and Muhammad Qasim. Natural product research 28.3 (2014): 185.
103
P11: Tunable Phenothiazine derivative for specific fluorescent sensing of hypochlorite
Ummu habeeba A A, S anandan*
Department of Chemistry, National Institute of Technology Trichy
Rational development of probes for the sensing of hypochlorite anion (OCl-) in the biological system is
a very significant topic. The presence of excess HOCl in the human body leads to permanent
damages in the human internal system and sometimes leads to cancer as well. We have designed
and synthesized phenothiazine based sensing probe TPT-3, which selectively detects the presence of
OCl- anion at biological pH. The sensing probe molecule TPT-3 is a Schiff base molecule, with a
phenothiazine donor fragment and dinitrophenylhydrazone as an acceptor fragment. Under
fluorescence light, TPT-3 in DMF-phosphate buffer is not fluorescent and upon addition of NaOCl
solution leads to intense green fluorescence at 488 nm, as given in figure 1. A gradual increase in
fluorescent intensity is observed with an increasing amount of NaOCl. The emission of intense
fluorescence in the presence of OCl- ion under UV light is expected to be due to the internal charge
transfer (ICT). ICT mechanism is supported by the solvatochromic studies. In higher polar solvents
TPT-3 exhibits red-shifted absorption peaks upon compared to relatively lower polar solvents. Further
theoretical data were provided to support the examination.
References:
1. Wu, D.; Chen, L.; Xu, Q.; Chen, X.; Yoon, J. . Acc. Chem. Res. 2019, 52 (8), 2158.
2. Cheng, X.; Jia, H.; Long, T.; Feng, J.; Qin, J.; Li, Z. A Chem. Commun. 2011, 47 (43), 11978.
3. Cheng, G.; Fan, J.; Sun, W.; Cao, J.; Hu, C. 2014, 1018.
300 400 500 600 700
0
2
Ab
so
rba
nc
e (
a.u
.)
Wavelength (nm)
tpt- cho.csv
tpt-3.+nocl.csv
tpt-3.csv
Fig.1. Fluorescence spectra
of TPT-3 with different
anions
Fig.2. Fluorescence image of
TPT-3 with NaOCl
Fig.3. UV-Vis spectra of TPT-3
104
P12: Tweaking the self-assembly of amyloid-like peptide fibres to hierarchical functional materials
Deepika Gupta,a Ashmeet Singh,
a Ranjan Sasmal,
b Jojo P. Joseph,
a Sarit Agasti,
b Asish Pal
a*
aInstitute of Nano Science & Technology, Mohali, Punjab-160062
bJawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064
Mimicking the out-of-equilibrium the self-assembly processes in nature is still a challenge for
scientists, employing thermodynamically controlled bottom-up self-assembly. In the realm of bio-
inspired material research, we take cue from amyloid beta sheet assembly and develop minimalistic
peptide fragments based on amyloid core. Perfect control over length regimes of the self-assembled
peptide nanofibers have been achieved through seeded living supramolecular polymerization. This, in
turn, renders precise control of the supramolecular peptide fibers in different length regimes.1
Structural and temporal control to differentiate the pathway was exploited for photodimerizable
peptide. It demonstrates the step-wise self-assembly to form nanoparticles, with eventual
transformation into 1D nanofiber. Addition of host moiety with subsequent irradiation with UV light
resulted to free-standing 2D nanosheets mediated by the host–guest interaction.2 Self-sorting is the
ability of mixtures to recognize their identical counterpart over the other non-identical one and result in
the formation of only selective and specific well-organized self-assembled structures rather that of all
possible unspecific complex architectures. Peptides can undergo a range of non-covalent interactions
and have the ability to recognize their own kind depending upon the side chain interactions and H
bonding. Peptides fragments differing in chirality are designed and self-assembly pattern of the
peptides with opposite chirality (L and D), are studied for molecular recognition. FRET technique is
used to investigate self-sorting phenomenon.3 Orthogonal self-assembly was envisaged through
seeded living polymerization through AFM imaging and ThT binding kinetics. Moreover, chirality
driven self-sorted peptide fibers were visualized through super resolution microscopy.
Figure: Visualization of chirality driven self-sorted self-assembled nanofibers.
References:
1. Singh, A.; Joseph, J. P.; Gupta, D.; Sarkar, I. Pal, A.; Chem. Commun., 2018, 54, 10730.
2. Joseph, J. P.; Singh, A.; Gupta, D.; Miglani, C.; Pal, A. ACS Appl. Mater. Interfaces 2019, 11,
28213.
3. Gupta, D.; Sasmal, R.; Singh, A.; Joseph, J. P.; Agasti, S.; Pal, A. Under review.
105
P13: Enhanced Selectivity in Julia-Kocienski Reaction Using Quaternary Ammonium Salt
Sravya Surendran, Mintu Rehman, Nagendra.S, Rajendar Goreti*
School of Chemistry, IISER Thiruvananthapuram
A new methodology is designed to improve E-selectivity in Julia-Kocienski reaction using quaternary
ammonium salt as an additive. We were indulged in the preparation of fragments necessary for the
total synthesis of rickiols, which uses Julia-Kociensky reaction as one of the key steps to prepare E-
selective olefin. The olefination of mannitol aldehyde by Julia-Kocienski reaction for E-olefin suffered
with poor selectivity, this may attributed due to chelation effect of substrate. Systematic investigations
to counter chelation effect by the use of highly non-coordinating counter cation leads to this new
methodology. Use of quaternary ammonium salts enhanced the selectivity to achieve targeted E-
isomer. Amongst different quaternary ammonium salts, tetrabutylammonium bromide (TBAB) worked
most efficiently to provide highest selectivity
References:
1. Pospíšil, Jiří. Tetrahedron Letters 52.18 (2011): 2348.
2. Baudin, J. B., et al." Bulletin de la Société chimique de France 130.6 (1993): 856.
3. Blakemore, Paul R, Journal of the Chemical Society, Perkin Transactions 1 23 (2002): 2563.
106
P14: Effective removal of Hg(II) from aqueous solution using petal-like MoS2 nanosheets
P. Ragini, Sambandam Anandan*
Nanomaterials and Solar Energy Conversion Lab, Department of Chemistry, National Institute of Technology, Tiruchirappalli-620 015, India
Few-Layered MoS2 nanosheets were synthesized via a surfactant-assisted hydrothermal method and
utilized them as an efficient adsorbent for the removal of mercury from aqueous solution. The
synthesized MoS2 nanosheets showed petal-like morphology as confirmed by SEM and TEM analysis.
Having high stability and negative zeta potential makes it suitable for the fast adsorption of mercury
from aqueous media. The adsorption efficiency of the adsorbent was investigated as a function of pH,
contact time and adsorbent dose. The kinetics of adsorption and reusability study of the adsorbent
was also performed. A pseudo-second-order kinetics for mercury adsorption was observed. As
prepared MoS2 nanosheets showed 87 % mercury removal efficiency whereas regenerated adsorbent
showed 80 % removal efficiency. The maximum adsorption capacity of the adsorbent was found to be
289 mg g-1
at room temperature.
Schematic diagram of the synthesis process of MoS2 nanosheets and adsorption of mercury on its surface.
References: 1. F. Jia, Q. Wang, J. Wu, Y. Li and S. Song, ACS Sustain. Chem. Eng., 2017, 5, 7410.
2. F. Jia, X. Zhang and S. Song, Phys. Chem. Chem. Phys., 2017, 19, 3837.
3. A. Gupta, V. Arunachalam and S. Vasudevan, J. Phys. Chem. Lett., 2015, 6, 739.
107
P15: Design, synthesis and evaluation of new 1,5-benzodiazepines as a versatile
pharmacophoric unit for the treatment of Cancer and Tuberculosis
Sinthiya Gawandi a, b
, Shrinivas Joshic, Fateh V Singh
d, Vidya Desai
a,b*.
aDepartment of Chemistry, Dnyanprassarak Mandal’s College & Research Centre, Assagao, Bardez
403507, India. b Goa University, Taleigao, Panaji 403206, India.
c Novel Drug Design and Discovery Laboratory, Department of Pharmaceutical Chemistry, S.E.T.’s
College of Pharmacy, Sangolli Rayanna Nagar, Dharwad 580 002, Karnataka, India. dDepartment of Chemistry, Vellore Institute of Technology, Chennai Campus, Tamil Nadu, India.
.
With the growing emergence for the development of novel drug targets as an antidotes for highly
dreaded diseases like cancer and tuberculosis a series of differently substituted new 2-Methyl-2,4-
diphenyl-2,3-dihydro-1H-benzo[1,5]diazepine derivatives of potential biological significance were
synthesized by condensation of o-phenylenediamine with differently substituted acetophenones using
catalytic amount of thiamine hydrochloride, a biocatalyst, under solvent free reaction conditions. The
in-vitro antimycobacterial activity against Mycobacterium tuberculosis H37Rv strains have been
evaluated for selected compounds. The results revealed that the compounds showed moderate anti
tubercular activity against Mycobacterium tuberculosis H37Rv strains. In-vitro cytotoxicity studies have
been examined against couple of cancer cell lines (HeLa and HEPG2) and normal human cell line
HEK-293. Compound 3x was found to be influential against both the cell lines with IC50 values of
0.067± 0.002 µM against HeLa and 0.087± 0.003 µM against HEPG2 cell line, having activity as
compatible to the standard drug Methotrexate. It was also potent against Mycobacterium tuberculosis
H37Rv strains with IC50 value of 6.25 µg/mL. All the screened compounds were proved to be nontoxic
with higher value of selectivity index.
.
References:
1. Trenton, A.; Currier, G. Prim. Care Companion J. Clin. Psychiatry. 2001, 3(6), 236.
2. Mazimba, O.; Molefe, T. Int. J. Chem. Studies, 2015, 3, 46.
3. Chen, L.; Bao, S.; Yang, L.; Zhang, X.; Li, B.; Li, Y. Res. Chem. Intermed. 2017, 43, 3883.
4. Salve, P.; Mali, D. Int. J. Pharm. Bio. Sci. 2013, 4, 345.
NH2
NH2R2
O
NH
N
R2R1
R1
R1
+ 2
solvent free
Biocatalyst
27 derivatives of 1,5-benzodiazepines
108
P16: Maximization of Photocatalytic and Photoelectrochemical Performance by Bi2WO6/TiO2-
Ag Ternary Composite
Jothivenkatachaam K,1* Kavinkumar V,
1 Sriramkumar M,
1 Moscow S,
1 Yen-Pei Fu
2
1Material Research Laboratory, Department of Chemistry, UCE-BIT Campus, Anna University,
Tiruchirappalli, Tamil Nadu 620024, India 2Department of Materials Science and Engineering, National Dong Hwa University, 97401 Taiwan
Utilization of free and green solar energy for the purification of polluted water and energy production
(H2 & O2 evolution) using semiconductor based metal oxide photocatalysis is a most hopeful
technique.1 Here, we have successfully synthesized ternary Bi2WO6/Ag/TiO2 photocatalyst via CTAB
assisted hydrothermal and simple chemical reduction method. As expected, co-induction of TiO2 and
Ag NPs on the surface of Bi2WO6 nanoplate, which is observed by the TEM images. From the XRD
patterns, the tetragonal for TiO2 and FCC for Ag phase peaks were gradually increased in the Bi2WO6
orthorhombic structure when increasing the concentration of precursor. Since, TiO2 as a conventional
semiconductor with a unique properties of low cost, non-toxic and mechanical stability which also
commercialized, however it couldn‟t active under solar light. Hence, visibly active bismuth (III) based
materials extensively attracted for the photocatalytic pollutant degradation and water splitting.
Bi2WO6/TiO2-Ag composite attained highest performance compared with bare Bi2WO6 and TiO2
materials due to the reduction of electron/hole recombination and increasing the absorption capability
by the SPR effect.2,3
Fig. P-XRD pattern (a) and UV-Vis DRS spectroscopy (b) of as-prepared materials
References:
1. Veerappan, K.; Dhayanantha, P. J.; Atul, V.; Kandasamy, J,; and Yen-Pei, F.; New J. Chem.,
2019, 43, 9170.
2. Arjunan, N.; Henry, L. J.; Karuppannan, R.; Kandasamy, R.; Kulandaivel, J.; and Kandasamy,
J.; Journal of Photochemistry & Photobiology, B: Biology, 2015, 153, 412.
3. Veerappan, K,; Atul, V,; Sriramkumar, M,; Sanath, K,; Kandasamy, J,; and Yen-Pei, F,; Dalton
Trans., 2019, 48, 10235.
109
P17: All Solid State Rechargeable Proton Battery
Neethu C D, Muhammed Musthafa O T*
Department of Chemistry, Indian Institute of Science Education and Research (IISER), Pune
Electric energy is an inevitable factor in our day to day life. Starting from our basic to industrial needs
requires electric energy. Due to industrial revolution energy conversion from non-renewable resources
(fossil fuels) rose exponentially. Even in this 21st century, we rely mostly on non-renewable resources
for large scale electricity production, which invariably emit greenhouse gases into the atmosphere at
an alarming rate to be neglected1. This add-up to global pollution as well as rise in global mean
temperatures. In this context, it was unambiguously decided to limit the global warming temperature
to 1.5oC during the UN conferences on climate change held in Paris on December 2015 and the same
voice was echoed in the subsequent years. To achieve this target we need to focus on electricity
production from the renewable energy resources2, utilization of which is greatly limited by their
characteristic fluctuations. This existing gap between availability and demand can be filled with
potential zero emission technologies such as batteries, fuel cells, supercapacitors and solar cells.
Recently, we have successfully demonstrated a rechargeable hydrogen battery based on the cleanest
energy carrier molecule hydrogen; by utilizing proton coupled electron transfer in hydrogen storage
molecule3. Working principle of this battery includes hydrogenation and dehydrogenation of hydrogen
storage molecules during discharging and charging respectively. However, we utilised the gaseous
hydrogen as the anode, which limits its practical usage. In order to overcome this we propose an all
solid state rechargeable proton battery by utilizing the principle of intercalation/de-intercalation of
protons in transition metal oxides and proton-coupled electron transfer in hydrogen storage
molecules. Electrochemical, spectroscopic, and spectroelectrochemical analysis evidence the
participation of protons during charge-discharge chemistry and extended cycling. In an era of
anthropogenic global climate change and paramount pollution, a battery concept based on protons
demonstrates distinct progress in the sustainable energy landscape.
References:
1. Bruce, P. G.; Freunberger, S. A.; Hardwick, L. J.; Tarascon, J.-M. Nat. Mater. 2011, 11, 19.
2. Chu, S.; Cui, Y.; Liu, N. Nat. Mater. 2016, 16, 16.
3. Neethu, C.D.; Thimmappa, R.; Manzoor Bhat, Z.; Devendrachari, M. C.; Kottaichamy, A. R.;
Gautam, M.; Shafi, S. P.; Thotiyl, M. O. J. Phys. Chem. Lett. 2018, 9 (10), 2492.
110
P18: Injectable Silk Hydrogel for Sustained Insulin Delivery in Diabetic Rats
Biswanath Maity, Sourav Samanta, Shradhya Sarkar, Shadab Alam, Thimmaiah Govindaraju*
Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre of Advanced
Scientific Research (JNCASR), Jakkur P.O., Bengaluru – 560064, Karnataka, India
Diabetes is a chronic disease affecting over 400 million people worldwide. Inadequate production of
insulin due to loss of beta cells or insulin resistance within the body imbalances the glucose
homeostasis, subsequent increased of blood glucose level. The conventional treatment involves
repeated subcutaneous insulin injections to maintain the physiological glucose homeostasis.
However, continuous and multiple subcutaneous injections are associated with poor patient
compliance and local amyloidosis of insulin, which can be overcome with sustained insulin delivery. In
this context, we have designed and formulated an injectable silk fibroin hydrogel (iSFH) for sustain
insulin delivery over a continuous time period under diabetic conditions. Interestingly, the
subcutaneous injection of insulin encapsulated iSFH (insulin-iSFH) in diabetic T1DM Wister rat
(induced by streptozotocin) released the insulin in a controlled way and restored physiological glucose
homeostasis up to 4 days. The biocompatible and biodegradable nature makes iSFH a potential and
active-drug delivery system for the sustained delivery of insulin.
References:
1. Zimmet, P.; Alberti, K. G.; Magliano, D. J.; Bennett, P. H. Nat. Rev. Endocrinol. 2016, 12, 616.
2. Manchineella, S.; Thrivikraman, G.; Khanum, K. K.; Ramamurthy, P. C.; Basu, B.;
Govindaraju, T. Adv. Healthc. Mater. 2016, 5, 1222.
3. Datta, L. P.; Manchineella, S.; Govindaraju, T. Biomaterials, 2020, 230, 119633.
4. Manchineella, S.; Govindaraju, T. In stimuli-responsive drug delivery systems, Singh, A.;
Amiji, M. M. Eds.; RSC publisher, 2018, 317.
5. Manchineella, S.; Thrivikraman, G.; Basu, B.; Govindaraju, T. ACS Appl. Mater. Interfaces
2016, 8, 22849.
111
P19: Facile Bile Salt-Induced Synthesis of Mesoporous MnO2 Nanoflowers: Applications in dye
removal, oxidation and supercapacitors
Ajay Kumar, Dillip G.R., A.J. Bhattacharyya, Uday Maitra*
Department of Organic Chemistry, Indian Institute of Science, Banaglore, 560012
MnO2 is an important functional oxide with wide applications such as in the oxidation of benzylic and
allylic alcohols, as an electrode material for supercapacitors, in the removal of dyes etc. In this
chapter, we demonstrated a simple, bile-salt induced synthesis of mesoporous (MP) MnO2 at neutral
pH from potassium permanganate. The physical properties of the synthesized MnO2 was found to be
dependent on the reaction temperature. This porous material with high surface area was used for the
adsorption of cationic organic dyes. Because of the exceptionally large surface area, we observed
significantly higher dye adsorption, and higher yields in standard oxidation reactions compared to
commercial samples of MnO2. Some of the results will be presented in this poster.
References:
1. Kim, H.; Wathanaphanit, A.; Saito, N. ACS Sustainable Chem. Eng. 2017, 5, 5842.
2. Hu, X.; Shi, L.; Zhang, D.; Zhao, X.; Huang, L.; RSC Adv. 2016, 6, 14192.
3. Harfenist, M.; Bavley, A.; Lazier, W. A. J. Org. Chem., 1954, 19, 1608.
18
HO R'
R
OR
R'
Dye adsorptionOxidation of benzylic alcohols
Methylene blue
112
P20: A Facile Approach for the Regioselective Preparation of 3-Halo-2H-Chromenones, 3-(2-
haloacetyl)-2H-Chromenones and Halogenated 2H-Chromenone Natural Products Promoted by
Oxone and NaX
Vanammoole Lakshmireddy, Vaidya Jayathirtha Rao, Bhimapaka China Raju*
Department of Organic Synthesis & Process Chemistry, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India.
2H-Chromenones are bio-active natural products and privileged compounds.1 2H-Chromenones
exhibit various biological and pharmaceutical properties. Regioselective halogenation is the
fundamental and potential reaction for the preparation of halogenated compounds. As part of our
ongoing research on Regioselective halogenation, we have reported acetanilides, benzanilides,
sulphonamides and heterocyclic compounds with oxone and NaCl/NaBr.2-4
The present work
describes the preparation of 3-halo-2H-chromenones, 4-substituted 3-halo-2H-chromenones and 3-
(2-haloacetyl)-2H-chromenones (Scheme I) by the halogenations of 2H-chromenones with
commercially available NaCl/NaBr and oxone. We also screened the various ammonium halides for
the present reaction and found chloride and bromide were facilitated the halogenations reactions.
Further, the method has been successfully applied for the preparation of pharmaceutically important
halogenated 2H-chromenone natural products such as Marmesin, Lomatin, Columbianetin, and
Decursinol. The present approach is simple and provides high yields of the target compounds.
Scheme I References:
1. Cao, D. Liu, Z.; Verwilst, P.; Koo, S.; Jangjili, P.; Kim, J. S.; Lin, W. Chem. Rev. 2019,
119, 10403.
2. Bikshapathi, R.; Prathima, P. S.; Rao, V. J. Green Chem. 2017, 19, 4446.
3. Reddy, V. L.; Prathima, P. S.; Rao V. J.; Bikshapathi, R. New J. Chem. 2018, 42, 20152.
4. Reddy, V. L.; Veera, Y. N.; Reddy, T. J.; Rao V. J.; Raju, B. C. Asian J. Org. Chem. 2019,
8, 1380.
113
P21: Reductive Ring Opening of Aroyl and Nitro-Substituted and γ-Butyrolactone fused
DonorAcceptor Cyclopropanes
S. Thangamalar, V. John Tamilarasan, K. Srinivasan*
School of Chemistry, Bharathidasan University, Tiruchirappalli-24.
Donor-acceptor (D-A) cyclopropanes (DACs) have received a great deal of attention in recent years
owing to their enormous synthetic potential.1 The ring opening and formal cycloaddition reactions of
D-A cyclopropanes constitute the basis for the majority of their synthetic applications. Our research
group has developed an expedient procedure for the access of aroyl and nitro-Substituted D-A
cyclopropanes as well as for γ-butyrolactone fused D-A cyclopropanes and is exploring their synthetic
utility.2,3
In continuation of our efforts, we have found that these cyclopropanes undergo reductive ring
opening upon catalytic hydrogenation or treatment with Zn/AcOH in alcoholic solvents to give ring
opened products (Scheme 1). Accordingly, aroyl-substituted D-A cyclopropanes 1 when treated with
Zn/AcOH in MeOH give aroyl-substituted arylethylmalonates 4, nitro-substituted D-A cyclopropanes 2
upon catalytic hydrogenation using H2/Pd/C in EtOH afforded arylethylmalonates 5 and γ-
butyrolactone fused D-A cyclopropanes 3 upon treatment with Zn/AcOH in MeOH furnished 3,4,5-
trisubstituted γ-butyrolactones 6. The products are not only versatile synthetic precursors for other
compounds, but also difficult to prepare by other methods. In the poster, we will present the details of
ring opening products obtained in the current studies and their synthetic applications.
Scheme 1
References:
1. Schneider, T. F.; Kaschel, J.; Werz, D. B. Angew. Chem., Int. Ed. 2014, 53, 5504.
2. Selvi, T.; Srinivasan, K. Isr. J. Chem. 2016, 56, 454.
3. (a) Tamilarasan, V. J.; Srinivasan, K. J. Org. Chem. 2019, 84, 8782. (b) Tamilarasan, V. J.;
Srinivasan, K. Eur. J. Org. Chem. doi:10.1002/ejoc.201901639.
114
P22: OXALIC ACID CATALYSED OXIDATION OF PHENOXY ACETICACID BY QUINALDINIUM
DICHROMATE-A KINETIC STUDY
T. Selvakumar, M. Venkatapathy, K. Anbarasu*
Department of Chemistry, Arignar Anna Govt. Arts College, Musiri – 621 211.
Oxidation of phenoxyaceticacid by quinaldinium dichromate (QnDC) in the presence of perchloric acid
and oxalic acid has been studied in 50% (v/v) aqueous acetic acid medium. The reaction shows unit
order dependence each with respect to oxidant and oxalic acid. The order with respect to substrate is
fractional and hydrogen ion concentration is inverse fractional. The rate of oxidation increases with
increase in the percentage of acetic acid and increase the ionic strength has negligible effect on the
reaction rate. Number of electron transferred during the oxidation process has also determined. The
thermodynamic and activation parameters have been calculated using Eyring‟s plot. From the kinetic
observations, the reaction mechanism and rate law has been proposed.
Reference:
1. Degirmenbasi, N. and Ozgun, B 2004, „QuinaldiniumFluorochromate and Quinaldinium
Dichromate: Two New and Efficient Reagent for the Oxidation of Alcohols‟, Monatshefte fur
Chemie, vol. 135, no. 4, pp. 407-410.
2. Koelsch, C. F 1931, „The Identification of Phenols‟, Journal of American Chemical Society,
vol. 53, no. 1, pp. 304-305.
115
P23: Direct Role of Methylmercury on alkylating DNA Lesion and its Remediation Strategy
using Functional Mimic of Organomercurial Lyase MerB
Ranajit Das; Ramesh Karri; Gouriprasanna Roy*
Department of Chemistry, Shiv Nadar University, NH91, Dadri, Gautam Buddha Nagar, Uttar Pradesh–201314, India
Methylmercury (MeHg+) is a potent neurotoxin that bio-accumulates at high levels in food chains, and
thus poses a significant health risk to human health. It is known to inhibit several important antioxidant
enzymes and also reduce the concentration of endogenous thiols like cysteine and glutathione in
tissues, and thereby increases the production of reactive oxygen species which lead to the oxidative
damage of biomolecules including DNA and protein.2 The high potency of MeHg
+ in producing DNA
damage compared to inorganic mercury Hg2+
in tissues is often recognized due to its striking ability to
easily cross the cellular membranes including the placental and blood-brain barriers. However,
contrary to its recognized indirect role on oxidative DNA damage, in this poster for the first time we
will show the direct effect of MeHg+ on alkylative DNA damage in the cellular system, in addition to the
oxidative DNA damage, which may account for its high cytotoxicity of organomercurials compared to
inorganic mercury.On the other hand, microbial methylation of inorganic mercury Hg2+
is the major
source of MeHg+ in nature and therefore, the demethylation of MeHg
+ is an extremely important
process for maintaining the net MeHg+ levels in the environment. In nature, mercury-resistant bacteria
having mer operon detoxify MeHg+ by producing a series of mer proteins including organomercurial
lyase MerB that catalyzes the protolytic Hg–C bond cleavage and produces Hg2+
and CH4.3 In this
poster, we will report a synthetic molecule which showed remarkable ability to protolytically cleave
Hg–C bonds of a wide variety of R–Hg–X molecules, including MeHg-DNA adduct (R = alkyl or aryl; X
= Cl, I, SPh or nucleoside) in the absence of exogenous thiols under mild conditions and thereby help
to protect DNA from alkylative or oxidative damage caused by MeHg+.
References:
1. Clarkson, T. W.; Magos, L. Crit. Rev. Toxicol. 2006, 36, 609.
2. Pieper, I.; Wehe, C. A.; Bornhorst, J.; Ebert, F.; Leffers, L.; Holtkamp, M.; Höseler, P.;
Weber, T.; Mangerich, A.; Bürkle, A.; Karst, U. Metallomics 2014, 6, 662.
3. Omichinski, J. G. Science 2007, 317, 205–206 Wahba, H. M.; Stevenson, M. J.; Mansour,
A.; Sygusch, J.; Wilcox, D. E.; Omichinski, J. G. J. Am. Chem. Soc. 2017, 139, 910.
116
P24: A hydrazide based reversible probe for Al3+
and sequential detection of PPi, ATP and ADP
in semi-aqueous medium
Sagarika Mishra, Sayed Muktar Hossain, Akhilesh Kumar Singh*
School of Basic Sciences, Indian Institute of Technology Bhubaneswar, Bhubaneswar, 751007, India.
Development of fluorescence chemosensors targeting multiple analytes recognition has led to a huge
surge of interest among researchers. Such systems are gaining wide attention due to their quick
response and cost effectiveness. Aluminum is one of the metals widely used in cookware, paper
industry, textile industry, water purification techniques and in the production of light alloy. However,
accumulation of aluminum in body results in the deposition of aluminum in different cells and tissues
leading to diseases like Al-related bone disease (ARBD), dementia, Alzheimer‟s disease,
etc. Similarly design of sensors for phosphate anions and derivatives such as HPO42-
,
pyrophosphates, adenosine triphosphate (ATP) and adenosine diphosphate (ADP) have dragged
special interest due to the vital roles played by these species in biological processes. Among other
detection techniques fluorescence spectroscopy stands apart, because of its simplicity, cost
effectiveness, sharp recognition, rapid and real time analysis and visual detection. A hydrazide based
Schiff base ligand, H2L has been synthesized and characterized by all spectroscopic techniques. In
this presentation selectivity and specificity of H2L (sensor 1) towards Al3+
in semi aqueous medium
(DMF/H2O mixture) by exhibiting a drastic increase in the fluorescence intensity will be discussed.
The L-Al3+
complex (sensor 2) generated in the solution acts as a sensor to sequentially detect
pyrophosphate groups present in inorganic pyrophosphate, ATP and ADP among other anions by
turning off the fluorescence. The results of emission studies, reversibile behavior, response to
variation in pH, life time and quantum yield will be highlighted.
Fig. 1. Logic Gate for Al3+
and P2O72-
as chemical inputs and fluorescence emission as
output.
References:
1. Wu, D.; Sedgwick, A. C.; Gunnlaugsson, T.; Akkaya, E. U.; Yoon, J.; James, T. D., Chem.
Soc. Rev. 2017, 46 (23), 7105-7123.
2. Wang, B.; Xing, W.; Zhao, Y.; Deng, X Environ. Toxicol. Pha. 2010, 29 (3), 308-313.
3. Rai, A.; Singh, A. K.; Tripathi, K.; Sonkar, A. K.; Chauhan, B. S.; Srikrishna, S.; James, T.
D.; Mishra, L Sensor Actuat B-Chem 2018, 266, 95-105.
117
P25: Operando Generated Intermetallic Ni3In as a Catalyst for the Selective Conversion of CO2
to Methanol
Arjun Cherevotan, Jithu Raj, Soumyabrata Roy, Sebastian C. Peter*
New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bangalore-
560064.
Amplified emission of carbon dioxide (CO2) due to anthropogenic activities is identified as the main
root of intensified global warming and climate change in recent years. The best way out suggested is
to hydrogenate CO2 back to fuel and is also identified as a “single stone two bird” approach to settle
both hiking energy demand and CO2 emissions.1, 2
Thermocatalytic routes of hydrogenation is
catalysed in industries by Cu/ZnO/Al2O3 (CZO) catalysts which utilizes high pressure of 50-100 bar
and 230-300°C.3 In this work we have used a rationale way of designing the catalysts for the efficient
conversion of CO2 to methanol. The well-known methanation catalyst nickel has been tuned with the
introduction of inactive indium for this purpose. We have selected the most stable intermetallic Ni7In3
supported on SBA-15, which was synthesized via incipient wetness impregnation. The optimized
reaction conditions in the thermochemical pathway favoured the in-situ transformation of Ni7In3 to
Ni3In (scheme), which favoured the conversion of CO2 to methanol instead of methane. This ordered
arrangement of atoms with the isolation of the active site nickel and electronegativity difference
between Ni and In are attributed to shift the mechanism towards methanol compared to methane in
the case of Ni/SBA-15.
Scheme: In-situ transformation of Ni7In3 to Ni3In during the catalytic CO2 hydrogenation.
References:
1. Goeppert, A.; Czaun, M.; Jones, J. P.; Prakash, G. K. S.; Olah, G. A., Chem Soc Rev 2014,
43 (23), 7995.
2. Roy, S.; Cherevotan, A.; Peter, S. C., ACS Energy Letters 2018, 3 (8), 1938.
3. Kattel, S.; Liu, P.; Chen, J. G., Journal of the American Chemical Society 2017, 139 (29),
9739.
118
P26: Substituent effect on second order non-linear optical properties of Y-shaped ferrocene
conjugated imidazole based D-π-A chromophores
Prabu Selvam, Nallasamy Palanisami*
Department of Chemistry, School of Advanced Sciences, Vellore Institute of technology, Vellore
632014, Tamil Nadu, India.
)
The donor-π-acceptor based chromophores have second order non-linear optical (NLO) properties is
an exciting discipline with important applications such as optical data storage, telecommunications,
optical switch, electro-optic modulator and NLO bioimaging.1,2
The donor-π-acceptor based bis-
ferrocenyl imidazole chromophores were synthesized and characterized by analytical and
spectroscopic techniques such as FT-IR, 1H and
13C NMR, and ESI mass. The structure is further
confirmed by single crystal X-ray diffraction studies. The solvatochromic studies reveals that non-
polar to polar solvents enhance the redshift for all the chromophores. The redox wave in
electrochemical studies of the chromophores evidenced the electron transfer ability of the bis-
ferrocenyl imidazole chromophores. The second-order nonlinear optical (NLO) properties were
determined by the Electric Field Induced Second Harmonic Generation (EFISHG) technique working
in CHCl3 solution with an incident wavelength of 1907 nm. The µβ1907 values of bis-ferrocenyl
imidazole chromophores and will be presented.
Figure: NLO-active Y-shaped chromophores.
References:
1. Prabu, S.; David, E.; Viswanathan, T.; Thirumoorty, K.; Panda, T.; Dragonetti, C.; Colombo,
A.; Marinotto, D.; Righetto, S.; Roberto, D.; Palanisami, N. Dalton Trans. 2020,
DOI:10.1039/C9DT03637G.
2. Prabu, S.; David, E.; Viswanathan, T.; Jinisha, J. S. A.; Malik, R.; Maiyelvaganan, K. R.;
Prakash, M.; Palanisami, N. J. Mol. Struct., 2020 (1202), 127302.
119
P27: Stress Induced Electronic Structure Modulation of Mn-incorporated Ni2P Leading to
Enhanced Activity for Water-Splitting
Shreya Sarkar, Lakshay Dheer, C. P. Vinod, Ranjit Thapa, Umesh V. Waghmare, Sebastian C. Peter
New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research Jakkur, Bangalore-
560064
The cornerstone of the emerging hydrogen economy is hydrogen production by water electrolysis with
concomitant oxygen generation. Although transition metal phosphides belong to a premier class of
water splitting electrocatalysts, their performance is not comparable to noble metals. Including a third
element to them can facilitate tuning of the crystalline and electronic structure and hence, improve the
electrocatalytic properties. In this work, Mn doped Ni2P with varying ratios of Mn and Ni has been
explored as excellent catalysts for efficient water splitting. A complete cell made of the best catalyst
Ni1.5Mn0.5P electrodes exhibits a low voltage of 1.7 V at a current density of 10 mAcm-2
as a result of
low onset potentials for HER (65 mV) and OER (1.45V). The high performance of Ni1.5Mn0.5P can be
accredited to enhanced electrical conductivity, induction of tensile stress, enhanced electrochemical
surface area, increased electric dipole due to Mn incorporation. Density functional theory (DFT)
demonstrates the intricately low hydrogen adsorption energy value for Ni1.5Mn0.5P accounting for its
highest HER activity whereas, for OER high affinity for oxygen and the presence of M-O species on
pristine and Mn-substituted Ni2P portrays the enhanced OER activity upon Mn substitution.
References:
1. Sarkar, S.; Dheer, L.; Vinod, C. P.; Thapa, R.; Waghmare, U. V.; Peter, S. C., 2020,
(Manuscript under review in ACS Applied Energy Materials).
120
P28: Ferrocene/ Non-Ferrocene Conjugated X-shaped Borasiloxanes for Luminescence and
Non-Linear Optical properties
Viswanathan Thamodharan, Nallasamy Palanisami*
Department of Chemistry, School of Advanced Sciences, Vellore Institute of technology, Vellore -
632014, Tamil Nadu, India.
Materials with second-order nonlinear optical (NLO) properties are of great interest since they can be
used for various important applications such as optical communication, optical data processing and
storage, and electro-optical devices. In this aspect, the donor-acceptor ferrocene/non ferrocene
conjugated X-shaped borasiloxanes were synthesized and characterized by various spectroscopic
techniques such as FT-IR, NMR, and HRMS. The charge transfer ability of both the borasiloxanes
were tested using solvatochromic studies and low fluoresence to enhanced fluoresence intensity was
achived by Aggregation-induced emission (AIE) studies through the principle of restriction of
intramolecular rotations (RIR) using THF: H2O mixture. The second-order nonlinear optical (NLO)
properties were determined by the Electric Field Induced Second Harmonic Generation (EFISHG)
technique working in DMF solution with an incident wavelength of 1907nm. The X-shaped ferrocene
conjugated borasiloxane shows enhanced NLO µβ1907 -435 × 10−48
esu. Further, these experimental
results were supported by density functional theory (DFT) at B3LYP/6-31+G** level of theory and will
be presented.
Figure 1. Chemical structure of X-shaped ferrocenyl/non-ferrocenyl borasiloxanes.
References:
1. Gopalakrishnan, M. Viswanathan, T. David, E. Thirumoorthy, K. Bhuvanesh, N. Palanisami,
N. New J. Chem. 2019, 43, 10948-10958.
2. Prabu, S. David, E. Viswanathan, T. Thirumoorthy, K. Panda, P. Dragonetti, C. Colombo, A.
Marinotto, D. Stefania Righetto, S. Roberto, D. Palanisami, N. Dalton Trans.,2020.
(Accepted).
121
P29: Y-shaped thiophene conjugated quinoxaline derivatives for photophysical and biological
applications
Ayilam Viswanathan Rajalakshmi, Nallasamy Palanisami*
Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore.
Thiophene derivatives have attracted wide attention of researchers as it has various applications such
as fluorescent1, metal ion sensors, anti-bacterial, solar cell and opto-electronic devices. Due to their
ease of synthesis and they are chemically stable, thiophene is one of the most studied heterocycles2.
In this aspect, we have synthesized Y- shaped thiophene conjugated quinoxaline derivatives 1-7 and
were characterized using analytical and spectroscopic techniques. All these derivatives exhibited
excellent fluorescence in solid as well as in solution state. Among them, the nitro substituted
derivative showed good aggregation induced emission (AIE)3 due to the formation of nano-aggregates
which was further characterized using DLS and SEM. These derivatives can also be used as potential
candidates for DNA-binding applications as well as for cancer cell-line studies and will be presented.
The synthetic route of thiophene conjugated quinoxaline derivatives
References:
1. Kaur, G., Kaur, N., Sensors and Actuators B: Chemical, 2018, 265, 134-141.
2. Stensrud, K.F., Zanotti, K.J., Waggoner., A.S., Armitage., B.A., Photochemistry and
photobiology, 2019, 95, 406-410.
3. Rajalakshmi, A. V., Palanisami, N., Spectrochimica Acta Part A: Molecular and Biomolecular
Spectroscopy, 117812.doi: 10.1016/j.saa.2019.117812 (In Press).
122
P30: Pincer-Nickel Catalysed N-Alkylation and Dehydrogenative Coupling Reactions
Vinay Arora,†a
Moumita Dutta,†a
Kanu Das,a Babulal Das,
a Hemant Kumar Srivastava,*
a Akshai Kumar
*a,b
aDepartment of Chemistry, Indian Institute of Technology Guwahati, Guwahati – 781039, Assam,
India. bCenter for Nanotechnology, Indian Institute of Technology Guwahati, Guwahati –781039, Assam,
India.
Nitrogen containing organic compounds are versatile intermediates that find immense synthetic value
as precursors to pharmaceuticals, agrochemicals, dyes and fine chemicals.1 Recent years have
witnessed a surge in the studies on direct N-Alkylation of amines using alcohols as the alkylating
agents. This is mainly attributed to its environmental friendly approach where water is the sole by-
product.2 However, these studies have been mainly limited to 4d and 5d transition metals.
3 Herein, we
report catalytic N-alkylation using Ni(II) NNN pincer complex with very high turnover (ca.34000
TONs).4
The reaction has been probed experimentally and theoretically to obtain a clear mechanistic
understanding. The studies have been extended to dehydrogenative coupling that results in formation
of benziimidazoles with high turnover (ca.2000 TONs).
References:
1. Lawrence, S. A., Amines: synthesis, properties and applications. Cambridge University
Press: 2004.
2. Dobereiner, G. E.; Crabtree, R. H., Dehydrogenation as a Substrate-Activating Strategy in
Homogeneous Transition-Metal Catalysis. Chemical Reviews 2010, 110 (2), 681.
3. Maji, M.; Chakrabarti, K.; Paul, B.; Roy, B. C.; Kundu, S. Adv. Synth. Catal. 2018, 360 (4),
722.
4. Arora.V.; Dutta, M.; Das, K.; Das, B.; Srivastava. K. H.,Kumar, A, Manuscript submitted.
123
P31: Palladium-catalyzed triflic acid-promoted regioselective hydroarylation of propiolic acid
with aryl boronic acids: An expedient access to α-aryl acrylic acids
Sayyad Basha Kolimi, Rengarajan Balamurugan*
School of Chemistry, University of Hyderabad, Hyderabad-500046, India.
Transition-metal (TM)-catalyzed hydroarylation reactions of alkynes have received much attention,
because they enable the net conversion of alkyne C≡C triple bonds into synthetically useful C=C
double bonds in a highly regio- and stereoselective manner1 In this line, a novel palladium-catalyzed
method has been developed for the synthesis of α-aryl acrylic acids from propiolic acid and aryl
boronic acids (Scheme 1). The α-aryl acrylic acids and their derivatives are important structural
moieties that widely exist in biologically active natural products and medicines. They also serve as
key precursors for a series of non-steroidal anti-inflammatory drugs (NSAIDs), such as naprosyn,
pirprofen, and fenoprofen.2
Scheme 1. Triflic acid-promoted palladium catalyzed regioselective hydroarylation of propiolic acid
with aryl boronic acids.
References:
1. (a) Hayashi, T.; Inoue, K.; Taniguchi, N.; Ogasawara, M. J. Am. Chem. Soc. 2001, 123,
9918. (b) Nevado, C.; Echavarren, A. M. Synthesis 2005, 2, 167. (c) Hanna, L. E.; Konev,
M. O.; Jarvo, E. R. Eur. J. Org. Chem. 2019, 184. (d) Manikandan, R.; Jeganmohan, M. Org.
Biomol. Chem. 2015, 13, 10420. (e) Song, S.; Yu, J. T.; Jiang. Y.; Jiang, C. J. Org. Chem.
2015, 80, 2855. (f) Fu, M. C.; Rui, S.; Cheng, W. M.; Fu, Y. ACS catal. 2016, 6, 2501.
2. (a) Windsor, M. A.; Hermanson, D. J.; Kingsley, P. J.; Xu, S.; Crews, B. C.; Ho, W.; Keenan,
C. M.; Banerjee, S.; Sharkey, K. A.; Marnett, L. J. ACS Med. Chem. Lett. 2012, 3, 759. (b)
Zhu, S.F.; Yu Y.B.; Li, S.; Wang, L.X.; Zhou, Q.L. Angew. Chem. Int. Ed. 2012, 51, 8872.
124
P32: Microbiologial and Spectral Studies of Anil and Benzimidazolium Fluorochromate
A. Samidurai K. Anbarasu*
Department of Chemistry, Arignar Anna Govt. Arts College, Musiri – 621 211.
The aromatic and heterocyclic ring systems are playing a very important role in pharmaceutical drug
synthesis. The present study was aimed to synthesis and evaluates the pharmacological latent of
heterocyclic compound such as chromium (VI) compound. Microbiological potential of the prepared
compounds anil and benzimidazolium fluorochromate were evaluated by disc diffusion method. Based
on the results, the prepared compounds anil and benzimidazolium fluorochromate were significant
potential against the selected organisms. The spectral characterization also revealed that the
prepared compounds have aromatic and heterocyclic ring system.
References:
1. Sivamurugan, V., Rajkumar, G.A., Arabindoo, B., Murugesan, V. Indian Journal of Chemistry
(B), vol. 44(1), pp. 144-147, (2015).
2. Bounar Rabah, Takia Lograda, Messaoud Ramdani Pierre Chalard a Gilles Feguiredo, Global
Journal of Research Medicinal Plants & Indigenous Medicine, vol. 2, No. 2, pp. 73-78, 2013.
125
P33: An Unprecedented Blueshifted Naphthalimide AIEEgen for Ultrasensitive Detection of 4-
Nitroaniline in Water via “Receptor-Free” IFE Mechanism
Mst Nasima Khatun,[a]
Arvin Sain Tanwar,[a]
Niranjan Meher,[a]
Parameswar Krishnan Iyer*[a],[b]
aDepartment of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, Assam, India
bCentre for Nanotechnology
, Indian Institute of Technology Guwahati
, Guwahati-781039, Assam, India
The development of a new naphthalene appended to a simple naphthalimide derivative (NMI) with
aggregation-induced enhanced emission (AIEE) property for the sensitive detection of 4-nitroaniline
(4-NA) in aqueous media is presented here. The newly designed naphthalimide AIEE gen has an
exceptional blue-shifted condensed state emission, that is devoid of any receptor, yet accomplished
ultrasensitive detection of 4-NA, one of the broad-spectrum pesticide that belong to the class III toxic
chemical, at parts per billion level (LOD/36 ppb, Ksv = 4.1× 104 M
−1) in water with excellent selectivity
even in the presence of potentially competing aliphatic and aromatic amines. The reported probe is
the first of its kind, demonstrating major advantages of receptor-free inner filter effect (IFE)
mechanism for the sensitive detection of 4-NA using an AIEE genic probe. Excellent sensitivity for 4-
NA is also achieved on paper-based test-strip for low-cost on-site detection.
References:
1. Khatun, M.N; Tanwar, A.S; Meher, N; Iyer, P.K. Chem. Asian J. 2019, 14, 4725.
126
P34: Rational control of hole injection and hole transport for high performance perovskite light
emitting diodes.
Ramesh Babu Yathirajula1, M.Adil.Afroz
2 , Ritesh Kant Gupta
1, Parameswar.K.Iyer
1,2,*
Centre for Nanotechnology1, and Department of Chemistry
2 , Indian Institute of Technology Guwahati,
Assam-781039.
Optoelectronic devices have been the most promising candidates in today‟s emerging technology.
Since the milestone study of light-emitting diodes (LEDs), enormous efforts following the pioneering
work have been focused on the improvement of devices in terms of their efficiency, stability and color
tunability, making them ideal for the future display and ambient lighting. Therein, LEDs have drawn
particular attention owing to their favorable merits of high efficiency, low cost, easy flexibility, large
area, high resolution, and low energy consumption in the full-color display and solid-state lighting
applications. We went for Nano Scale fabrication. Perovskite LEDs with a structure of
FTO/NPD/PEROVSKITE Active layer/TPBi/LiF/Al . We achieved the brightness of 24,343 cd/m2
, EL
Spectra at 533nm and CIE coordinates(0.22,0.74).The above device parameters for the champion
device. Perovskite Solution made with (1.1:1) ratio of MABr and PbBr2. NPD acting as a Hole
transporting layer & TPBi acting as a Electron transporting Layer. We compared different hole
transporting layers like PVK, PEDOT: PSS and TCTA.
References:
1. B. Zhang, C. Qin, J. Ding, L. Chen, Z. Xie, Y. Cheng, and L. Wang, Adv. Funct. Mater. 20,
2951 (2010)
2. H. B. Wu, J. H. Zou, F. Liu, L. Wang, A. Mikhailovsky, G. C. Bazan, W. Yang, Y. Cao, Adv.
Mater. 20, 696 (2008)
3. J. H. Zou, H. Wu, C. S. Lam, C. D. Wang, J. Zhu, C. M. Zhong, S. J. Hu, C. L. Ho, G. J. Zhou,
H. B. Wu, W. C. H. Choy, J. B. Peng, Y. Cao, W. Y. Wong, Adv. Mater. 23, 2976 (2011)
4. B. H. Zhang, L. H. Liu, G. P. Tan, B. Yao, C. L. Ho, S. M. Wang, J. Q. Ding, Z. Y. Xie, W. Y.
Wong, L. X. Wang, J. Mater. Chem. C, 1, 4933 (2013)
5. Z. Xiao, R. A. Kerner, L. Zhao, N. L. Tran, K. Lee1, and B. P. Rand, Nature Photonics, 11,108
(2017)
127
P35: Enhancing the Power Conversion Efficiency of organic solar cell by Incorporating Cost
Effective 2,5-Difluorobenzene Units into the Polymer Backbone via Random Copolymerization
Maimur Hossain1; Parameswar K Iyer
1,2*
1Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, Assam, India
2Centre for Nanotechnology
, Indian Institute of Technology Guwahati
, Guwahati-781039, Assam, India
Two new random terpolymers m1PTB7-Th and m2PTB7-Th have been designed and synthesized by
incorporating a significantly low cost 2,5-Difluorobenzene in donor polymer for the application in
organic photovoltaics (OPVs). Replacing 5 and 10 mol% of extremely expensive 3-fluorothieno[3,4-
b]thiophene-2-carboxylate monomer in the well-known PTB7-Th by a > 100-times lower cost 2,5-
Difluorobenzene the new terpolymers m1PTB7-Th and m2PTB7-Th shows deeper HOMO energy
level and comparable LUMO energy level because of this, there is a significant increase in Voc which
helps to achieve higher power conversion efficiency (PCE) of 8.78% (Voc=0.850 V ) with m1PTB7-Th
compare to 7.90% for PTB7-Th (Voc=0.780 V) and the 4.0% (Voc= 0.890 V) for m2PTB7-Th in bulk
heterojunction photovoltaic device with the structure of ITO/PEDOT:PSS/Donor:PC71BM (1:1.5,
w/w)/Ca/Al by using 3% of 1,8-diiodooctane (DIO) as solvent additive in the active layer.1 By using
this low cost monomer incorporation in random copolymerization high performance polymer with
improved Voc can be achieved.
Reference:
1. J. Gao, W. Wang, S. Zhang, S. Xiao, C. Zhan, M. Yang, X. Lu and W. You, J. Mater. Chem. A,
2018, 6, 179
128
P36: Suppression of Aggregation Caused Quenching in Pyrene by Introducing Different Rotor
Groups: Photo-physical Studies and Hydrazine Sensing
Laxmi Raman Adil1 and Parameswar K. Iyer*
1,2.
1Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, Assam, India
2Centre for Nanotechnology
, Indian Institute of Technology Guwahati
, Guwahati-781039, Assam, India
Luminescent compounds have attracted considerable attention since the discovery of the
fluorescence (1565) by Nicolás Monardes.1 Although fluorescent compound developed over
centuries, however still it is considered a dynamic research area. Fluorescent materials have broad
applications viz. metal ion sensing, biosensing, cell imaging, organic light-emitting diodes (OLED).2-3
Generally, all the traditional fluorescence materials have intense emission in dilute solution or less
concentration but low or no emission in higher concentration due to robust intermolecular interactions.
This behavior of fluorophore termed as aggregation-caused quenching (ACQ). In contrary to
established ACQ, some new material aggregates have constructive effects in fluorescence this
phenomenon is termed as aggregation-induced emission (AIE).4
Hydrazine extensively used as a chemical reagent for various synthesis experiments and in rocket
fuel as well. Hydrazine is listed as a carcinogen agent and it is highly toxic that caused serious threats
to human and marine life system. Hence detection of hydrazine has attracted immense attention. We
designed and synthesized three pyrene based derivatives PP, PBA,PBM, PBT,PBBT and PBI . We
studied their photo-physical properties and we performed selectively sensing of hydrazine in water
system with higher sensitivity and selectivity.
Figure 1: Pictorial repre. of the formation of pyrene derivative aggregates in an aqueous medium..
References:
1. Valeur, B.; Berberan-Santos, M. N. J. Chem. Educ. 2011, 88, 731−738.
2. Gopikrishna, P.; Das, D.; Adil, L. R.; Iyer, P. K. J. Phys. Chem. C, 2017, 121, 18137−18143.
3. Tanwar, A, S.; Adil, L. R.; Afroz, M. A.; Iye, P. K. ACS Sens. 2018, 3, 1451−1461.
4. Adil, L. R.; Gopikrishna, P.; Iyer, P. K. ACS Appl. Mater. Interfaces, 2018, 10, 27260−27268.
129
P37: Low-cost Mixed Halide Perovskite Thin Film Transistor: Role of Active Layer Morphology
and Leakage Current through Dielectric
Anwesha Choudhury1, Parameswar Krishnan Iyer
1,2*
1Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati-781039, Assam, India
2Centre for Nanotechnology
, Indian Institute of Technology Guwahati
, Guwahati-781039, Assam, India
Organic-inorganic perovskite has gained popularity in recent times because of its high carrier
mobility[1], easy and low cost processing for various as active material for Field Effect
Transistor(FET). Selection of the Gate Insulator (Dielectric) plays an important role in controlling the
leakage current through gate insulator of FETs. In this paper we have demonstrated the variation of
the growth and nucleation of perovskite thin film on various dielectric layers. Thereafter we report the
fabrication and characterization of perovskite FET. We propose that growth of the perovskite depends
on the dielectric layer on which it is coated. MACl and PbI2 based perovskite forms a stable film and
the nucleation depends on the aging of the precursor solution. Hence by controlling of the perovskite
film morphology, a high performing device can be obtained. Hence a low cost and well performing
TFT is reported.
Figure1: Perovskite TFT structure. (Schematic view of the transistor with Cu source drain)
Glass Substrate
Aluminium Gate ContactAnodised Al2O3 (Dielectric 1)
Polymer Dielectric Layer PVA_3% (Dielectric 2)
Perovskite Active Layer
Cu
SourceCu
Drain
Polymer Dielectric Layer PMMA 1%(Dielectric 3)
130
P38: Effective Catalytic Activity of Mononuclear Copper(II) Complexes: Dimeric Association
and Positive Redox Potential Pave the Way to Analogous the Function of Copper Oxidases
Balakrishnan Sasikrishnan, Mariappan Murali*
Coordination and Bioinorganic Chemistry Research Laboratory, Department of Chemistry, National College (Autonomous), Tiruchirappalli 620 001 Tamil Nadu
Copper containing metalloenzymes are very efficient natural catalysts involved in a great variety of
reactions. In particular, ascorbate oxidase (AO) catalyzes ascorbic acid to dehydroascorbate. It
belongs to the functional trinuclear copper cluster and the type-2 active site of copper(II) consists of
two histidine molecules and a water molecule. Amine oxidase (AmO) is one of the type-2 copper
oxidases occurs as homodimers and the geometry of the copper(II) active site is square pyramidal
surrounded by three imidazole and two water molecules, which form a N3O2 chromophore with two
labile O-donor sites. AmO catalyzes amine to aldehyde in a reaction RCH2NH2 RCHO + NH3,
which is an important deamination reaction, involves two electron enzymatic processes. A type-3
copper enzyme, such as catechol oxidase (CO) consists of mainly dinuclear copper, each coordinated
by three imidazoles from the histidine residues and the dicopper center is bridged by the oxy form of
-2:
2 peroxo moiety in its active site. It oxidizes catechol to o-quinone in the presence of dioxygen.
Though numerous dinuclear copper(II) complexes successfully mimic the enzyme, both structurally
and functionally, a great number of mononuclear copper(II) complexes too are known to show copper
oxidase activity. The mixed ligand mononuclear copper(II) complexes of the type [Cu(L1)(L2)] where
L1 and L2 together give a square-pyramidal (4+1) coordination geometry with labile binding site(s) are
important to investigate their oxygen transfer process with ascorbic acid and benzylamine oxidation.
However, a non-planar geometry around copper(II) is necessary for mononuclear complexes to be
active for catechol oxidation. Thus, we have synthesized two green coloured mononuclear copper(II)
complexes of the type [Cu(L1/L2)(phen)](ClO4) where the Schiff base is obtained from the
condensation of salycilaldehyde and N,N-dimethylethylenediamine (HL1) (1) or 2-(2-
aminoethyl)pyridine H(L2) (2) and phen is 1,10-phenanthroline. Single crystal X-ray analysis of 1 and
2 exhibits the distorted square pyramidal geometry and shows self-assembled dimeric association.
They exhibit d-d and charge transfer transitions and reversible and positive CuII/Cu
I redox couple.
Frozen DMF solution spectra show hyperfine structure while MeOH and MeCN display broad isotropic
resonance, which indicates the presence of dimeric association in solution. The complexes are
catalytically more effective in the oxidation of ascorbic acid to dehydroascorbic acid (100:1), amine to
aldehyde (100%) and 3,5-di-tert-butylcatechol to 3,5-di-tert-butylquinone (Kcat; 1, 2148; 2, 1722 h-1
)
using dioxygen, which models the functional activity of copper oxidases.
References:
1. Sathya, V.; Murali, M. Inorg. Chem. Commun., 2018, 92, 55.
2. Sathya, V.; Murali, M. Inorg. Chim. Acta, 2019, 496, 1190.
131
P39: Selective Cytotoxic Activities of Ruthenium(II) Complexes on MCF-7 and HeLa Cancer
Cell Lines
Balasubramaniam Selvakumaran, Mariappan Murali*
Coordination and Bioinorganic Chemistry Research Laboratory, Department of Chemistry, National College (Autonomous), Tiruchirappalli 620 001 Tamil Nadu
Although cisplatin has an excellent results in the treatment of some types of cancer, its efficacy is
limited due to high toxicity and treatment resistance development. In this context is necessary the
development of new and more effective anti-cancer agents, such as complexes based on ruthenium,
which represent a more effective and less toxic alternative for treatment. Some theories suggest that
ruthenium complexes are more specific and less toxic due to the advantages that represent their
various oxidation states, as well as their resemblance to elements such as iron, and the union to
biomolecules of transport as transferrin. The selectivity of drugs is very important in cancer treatment
because if this is low the consequences of treatment are reflected in serious side effects because
they affect both tumor cells and non-tumor cells. Therefore, novel ruthenium(II) complexes of the type
[Ru(bpy)2(en(1)/dmen(2)/deen(3))](PF6)2 (bpy, 2,2‟-bipyridine; en, ethylenediamine; dmen, N,N-
dimethylethylenediamine; deen, N,N-diethylethylenediamine) were synthesized. In 1 and 2, two bpy (1
and 2) and en (1) or dmen (2) engaged in bidentate coordination to Ru(II) center, in the expected
distorted octahedral fashion. The 1H NMR spectral studies on the complexes throw light on the nature
of metal-ligand bonding and the conformations of the chelate rings. The electronic and emission
spectral and electrochemical characterization has been accomplished. All the complexes have been
explored for anticancer activity to MCF-7 and HeLa cells. Notably, complexes 2 (MCF-7: IC50, 28; SI,
> 8.7 and HeLa: IC50, 36; SI, > 6.8) and 3 (MCF-7: IC50, 42; SI, > 5.9 and HeLa: IC50, 31; SI, > 8.0)
exhibit selective cytotoxicity to both the cancer cells while 1 (MCF-7: IC50, 209; SI, > 1.2 and HeLa:
IC50, 192; SI, > 1.3) is highly inactive. The complexes 2 and 3 were non-toxic to MDBK (normal cells)
signifying target-specific nature of antitumor activity. Increased ROS concentration, as probed by
DCFDA assay for complex 2, in the MCF-7 cancer cells was responsible for apoptotic cell death.
Interestingly, complex 2 induces severe intracellular organelles such as cell membrane, actin
cytoskeletal and mitochondria. FACS analysis showed G1 phase cell-cycle arrest in MCF-7 cells
when treated with complex 2. The results of 2 and 3 displayed evidence of higher antiproliferative
activity in tumor cells with an important index of selectivity when compare with normal cells. Hence,
these two ruthenium(II) complexes would be a potential agent for the treatment of breast and cervical
cancers.
References
1. Pieter, B. C. A.; Sadler, P. J. Curr. Opin. Chem. Biol., 2008, 12, 197-206.
2. Allardyce, C. S.; Dyson, P. J. Platinum Metals Rev., 2001, 45, 62-69
3. Badisa, R. B.; Darling-Reed, S. F.; Joseph, P.; Cooperwood, J. S.; Latinwo, L. M.; Goodman,
C. B. Anticancer Res., 2009, 29, 2993-2996.
132
P40: ε-Lactones and ε-Lactams via [4+3]-Annulation and 3,4-Dihydrocyclopenta[b]indoles via
Decarboxylative Cyclization Using Indole Carboxylic Acids/Amides and Propargyl Alcohols
Shubham Debnath, Karuppu Selvaraj, K. C. Kumara Swamy*
aSchool of Chemistry, University of Hyderabad, Hyderabad-500046, Telangana, India
Indole fused five or seven membered rings (cyclopentene or ε-lactone and ε-lactam) are often found
as structural motifs in many natural products and synthetic drugs.1 In recent years, there is a growing
interest in the biological activities of ε-lactams/ε-lactones. The 3,4-dihydrocyclopenta[b]indole
skeleton, which can be considered as indeno[2,1-b]indole,2 is important because it has been mapped
in a route to cyanobacterial alkaloid. On the other hand, decarboxylative cyclization has emerged as a
powerful tool for the synthesis of acyclic/polycyclic, natural/un-natural compounds.3
In continuation of
work on the chemistry of propargylic systems,4 we herein demonstrate one-pot, metal-free
decarboxylative cyclization of indole 2- or 3-carboxylic acids with propargyl alcohols for the synthesis
of highly substituted ε-lactones, ε-lactams and 3,4-dihydrocyclopenta[b]indoles. The interesting part of
this work is that unexpected carboxamide migration took place to the indole-2-position during the
reaction of indole-3-carboxamide and propargyl alcohols.
References:
1. Selvaraj, K.; Debnath, S.; Kumara Swamy, K. C. Org. Lett. 2019, 21, 5447.
2. Zhang, L.; Zhu, Y.; Yin, G.; Lu, P.; Wang, Y. J. Org. Chem. 2012, 77, 9510.
3. Weaver, J. D.; Recio, A.; Grenning, A. J.; Tunge, J. A. Chem. Re ,2011, 111, 1846.
4. Selvaraj, K.; Kumara Swamy, K. C. J. Org. Chem. 2018, 83, 15043.
133
P41: Regioselective Synthesis of Pyrrolopyridine Derivatives under Mild Conditions
Manisha Choyal, Akanksha Agarwal and Neelima Gupta*
Centre of Advanced Study, Department of Chemistry, University of Rajasthan, Jaipur-302004, India
Pyrrolopyridine nucleus is constituent of many important naturally occurring bioactive alkaloids. Efforts
have been made to synthesize pyrrolopyridines having variety of substitution patterns with potential
importance in both synthetic and medicinal chemistry. 1,3-Dipolar cycloaddition reaction of pyridinium
ylides is a widely applied method for the synthesis of Indolizine derivatives. Under present
investigation, libraries of unsymmetrically substituted indolizine derivatives under milder conditions
without using any oxidizing agent have been synthesized. Interesting observations pertaining to
various compositions of regioisomers have been made. Auto-aromatisation of the cycloadduct under
milder conditions has been achieved. The reaction mechanism has been investigated by
computational calculations at DFT (B3LYP/6-31+g**) level to examine observed regioselectivity using
unsymmetrical dienophile. The experimental yield of the products is sufficient and spectroscopic
techniques - 1H-NMR,
13C-NMR and HRMS have been used for characterization of products.
Biomolecular interactions of selected representatives have been identified using Docking studies.
134
P42: Impact of stereo-electronic properties of a molecule on CEST efficiency
Subhayan Chakraborty and Arindam Ghosh*
School of Chemical Sciences, National Institute of Science Education and research, Bhubaneswar
Chemical exchange saturation transfer (CEST) NMR is widely used for a number of applications
including identification of low population states in proteins1 and study of ligand-binding
2. Very recently
CEST has found a new application in the form of proton density tuning for MRI imaging. CEST
contrast agents are exogenous or endogenous compounds that contain exchangeable protons, which
are selectively saturated and after transfer of this saturation to solvent water, the depletion of the
water signal intensity is used for contrast during the imaging process. Over the past few decades this
new generation of contrast agents has evolved as a good competitor of the widely used Gd (III)
contrast reagents. CEST contrast agents are broadly divided in two categories, Dia-CEST (without
metal ion) 3
agents and para-CEST (with metal ion) 4
agents. In either category, to achieve a good
CEST contrast tuning the stereo-electronic properties and plausibility of intramolecular hydrogen bond
within the molecule becomes extremely important, as it governs the chemical environment of the
exchangeable moiety which in turn influences the MTR asymmetry. Moreover, in case of para-CEST
contrast agents, the type of free base used for forming the metal complex as well as the induced
magnetic properties at the metal center in solution plays important role in making an effective CEST
based contrast agent. Apart from the chemical properties of the reagent, determining and calibrating
saturation pulse parameters like pulse-power, pulse-shape, saturation duration, saturation offset,
recycle delay are also important as mistune of any one of these can potentially have dramatic effect
on the success of the experiment even with a very fine contrast agent. In this presentation we
demonstrate the effect of these important parameters on the CEST contrast capability of few recently
proposed4 and widely known CEST contrast agents.
References:
1. Vallurupalli et al. Journal of American chemical society, 2012, 134, 19, 8148
2. Binbay et al. Universal journal of public health 5(6) 320, 2017
3. Sangeeta ray Banerjee et al. Chemistry A European journal, 2018, 24, 7235
4. Rabindra N. Pradhan, Subhayan Chakraborty, Pratibha Bharti, Janesh Kumar, Arindam
Ghosh,* and Akhilesh K. Singh* Dalton trans, 2019,48, 8899.
135
PP43: Synthesis, Reactivity and Emission Properties of Copper, Zinc and Cadmium
Formylbenzoate Complexes
Jitendra Nath, Arup Tarai, Jubaraj B. Baruah*.
Chemistry Department.Indian Institute of Technology, Guwahati 781039, India.
To probe the changes in aggregation induced emission and chemo-sensitivity of low-nuclearity metal
complexes caused by different pollutants on 1,10-phenanthroline containing formylbenzoate
complexes of zinc, copper and cadmium, several low nuclearity complexes were synthesized and
characterized. These complexes were designed so as to understand the possible effect of emission
through a pull-push mechanism as illustrated in figure 1a or by chemical reactivity of the aldhehyde
group on the ligand. The d10
- zinc and cadmium complexes were weakly fluorescent and their
emissions changed upon interactions nitro-anilines to use them for sensing purposes. The quenching
caused by 4-nitroaniline by the zinc complex is shown in the Figure 1b. The photo-luminescence was
studied by study on the photo-luminescence decay profiles and also by dynamic light scattering
experiments. We also explored the reactivities of copper(II) formylbenzoate complexes towards
hydroxyl-amine and established structure of an unusual complex formed by C-H activation of
aldehyde and also have characterised an inclusion complex of bis(1,10-
phenanthroline)(chloro)copper(II)chloride encapsulating ((hydroxyimino)methyl) benzoic acid in the
hydrogen-bonded chloride-hydrate assembly formed by self-assembling. The presentation will include
the synthetic, characterisation of those complexes and elucidation of the emission properties of those
complexes.
(a) (b)
Fig. 1: (a) Electronic push−pull effect in a portion of a metal complex. (b) Fluorescence quenching of
bis-phenanthroline zinc formylbenzoate complex by different amounts of 4-nitroaniline
Reference:
1. Nath, J.; Tarai, A.; Baruah, J. B. ACS Omega 2019, 4, 18444 −18455.
136
PP44: Visible-Light-Induced Oxidative Cleavage of C-C Triple Bond via Hydroamination: Direct
Synthesis of Oxamates from Amines and Activated Alkynes
Narenderreddy Katta, and Duddu S. Sharada*
Department of Chemistry.Indian Institute of Technology- Hyderabad
The direct oxidative cleavage of activated alkynes via hydroamination has been described using
organic photocatalyst under visible-light irradiation at room temperature. In this reaction, the single
electron oxidation of an in situ formed enamines undergo radical coupling with oxidant which finally
delivers the oxamates. The key features of this photocatalytic reaction are the mild reaction
conditions, metal-free organic dye as a photocatalyst, TBHP plays a dual role as “O” source and for
the regeneration of photocatalyst.
References:
1. Katta, N.; Ojha, M.; Murugan, A.; Sagar, A.; Sharada, D. S 10.26434/chemrxiv.7322402
2. Sagar, A.; Katta, N.; Ajoy, C.; Sharada, D. S Eur. J. Org. Chem. 2019, 7, 1542.
3. Babu, V.N.; Murugan, A.; Katta, N.; Sharada, D. S. J. Org. Chem. 2019, 84,6631.
4. Murugan, A.; Babu, V.N.; Sabari, N.; Sharada, D. S. J. Org. Chem. 2019, 84,7796.
137
P45: Use of Dimeric Excited States of the Donors in D4-A Systems for Accessing White light
Emission, Persistent Room Temperature Phosphorescence and Invisible Security Ink
Harsh Bhatia, Debdas Ray*
Department of Chemistry, Shiv Nadar University
Pure organic white light emitters with persistent room temperature phosphorescence (RTP) feature
have unique advantages and various potential applications. However, the studies of single-
component organic white light emitters with persistent RTP and visible light excitation (VLE)-
dependent efficient RTP features remain a challenging area of research in photophysics. Herein, we
synthesized three terephthalonitriles derivatives in which 2,3,5,6-positions are covalently attached to
2-fluoro-phenoxy (TOF), 2-chloro-phenoxy (TOC), and 2-methoxy-phenoxy groups (TOM)1 to give
twisted geometries. We observed that powder samples of both TOC and TOM show white light
emission with CIE coordinates of (0.32, 0.38) and (0.26, 0.33), respectively, while TOM gives VLE-
dependent efficient RTP under ambient conditions. In addition, both TOC and TOF exhibit a dim
afterglow feature. Spectroscopic studies reveal that emission of these chromophores originates via
radiative decay of monomeric excited states (singlet, triplet), dimer-like excited states (DLES) (singlet,
triplet), and aggregated triplet states. Detailed spectroscopic and X-ray analyses reveal the signature
of DLES that is formed via conformational reorganization of the phenoxy donors in the excited states.
Single-crystal X-ray diffraction analysis shows that the multiple lp(O)···π(C≡N)/C≡C, Cl/F···π, and
hydrogen-bonding interactions in the X-ray structures play a significant role in facilitating intersystem
crossing2, stabilizing multiple triplet states, and suppressing non-radiative decay, thereby triggering
dim afterglow under ambient conditions. We found that TOC and TOF exhibit persistent RTP with
lifetimes of 139 and 736 ms, respectively, when embedded in polyvinyl alcohol matrix. Given the
persistent RTP feature, invisible security ink application is developed.
Figure: Fluorescence and Phosphorescence emission from a single molecule in powder form at room
temperature using monomer, dimer and aggregates for white light emission.
References:
1. Bhatia, H.; Ray, D.; J. Phys. Chem. C 2019, 123, 22104-22113.
2. El-Syed, M. A.; J. Chem. Phys. 1963, 38, 2834-2838.
138
P46: Optical Detection and Separation of Heavy Metal Ions Using Chitosan based Hydrogels
Megha Sara Jacob, R Liju, E Rajkumar*
Department of Chemistry, Madras Christian College, Chennai, 600059
The continuous growing trend of industrialization and globalization has set heavy metals among the
prominent sources that augment environmental pollution. The concern regarding the remediation of
the natural ecosystem has drawn a great multitude of scientists towards the detection and separation
of heavy metals. The present work is based on designing and synthesizing a polymeric hydrogel for
the absorption and separation of heavy metals in solutions. Chitosan, the second most abundant
biopolymer, was crosslinked via a suitable crosslinker to enhance its structural stability and
properties. The obtained gels were characterized via IR spectroscopy and its surface morphology
studied by using SEM technique. Hydrogels containing carbon dots exhibited enhanced absorption of
heavy metals through complex formation. The absorbed metal ions gave rise to characteristic colours
that can be observed through naked eye thereby providing qualitative results. The interesting results
are discussed during the presentation.
Reference:
1. Neelam Gogoi.; Mayuri Barooah.; Gitanjali Majumdar.; Devasish Chowdhury. ACS Appl. Mater. Interfaces 2015, 7, 5, 3058-3067.
2. Matthew D. Cathell.; JanahC.Szewczyk.; Frances A. Bui.; Carrie A. Weber.; Jessica D
.Wolever.; Jennifer Kang.; Caroline L. Schauer. Biomacromolecules 2008, 9, 289- 295.
139
P47: Tuning thiaza[5]helicenes for better optoelectronic properties - A DFT and TDDFT study
R.Lipin and Rajadurai Vijay Solomon*
Department of Chemistry, Madras Christian College, Chennai, 600059
For the past 100 years helicenes are found to be useful in many fields due to its fascinating chiral,
physical, electronic and optical properties. Substituents in the bay area, also called the fjord region
of helicenes are known to increase the enantiomerization barrier and torsion angle in the structure. A
recent study shows that substituting at the bay region also influence the spectroscopic properties in
addition to the solid state structure. In the present study, Thiaza[5]helicenes derivatives have been
designed and screened for better optoelectronic properties using DFT and TDDFT calculations. The
main focus of this work is to understand and analyse the structure-property relationship of these
derivatives and to offer insights to design new Thiaza[5]helicene candidates for optoelectronic
applications.
Figure: Structure of bay-substituted thiaza[5]helicene
References:
1. Marc Gingras. Chem. Soc. Rev., 2013, 42, 1051.
2. Ravat, P.; Hinkelmann, R.; Steinebrunner, D.; Prescimone, A.; Bodoky, I.; Jurí ek, M. Org.
Lett. 2017, 19, 3707.
3. Mathias Daniels.; Flip de Jong.; Tom Vandermeeren.; Luc Van Meervelt.; Mark Van der
Auweraer.; Wim Dehaen. J. Org. Chem. 2019, 84, 21, 13528.
4. R. Vijay Solomon.; P. Veerapandian.; S. Angeline Vedha.; P. Venuvanalingam. J. Phys.
Chem. A 2012, 116, 4667.
140
P48: Enzyme mimicking activity of triggered MCM-41 incorporating Co(II) Schiff base complex
Manikandan Palaniappan, Selvi Arumugam, Rubiga Muthusami, Rajavel Rangappan*
Department of chemistry, Periyar University, Salem-11
(
Co(II)–Schiff base complex was achieved by the condensation of acenaphthylene-1,2-dione, S-
methylbenzyldithiocarbazate and 3-aminopropyl triethoxy Silane (3-APTES) with cobalt acetate. The
mesoporous material MCM-41 was incorporated using synthesized Co(II)–Schiff base complex for
enzyme catalytic efficiency. The catalyst was characterized by various techniques such as elemental
analysis, SEM, TEM, LA-XRD, FTIR, N2 adsorption–desorption, TG-DTA, solid state UV–vis and XPS.
LA-XRD and adsorption–desorption analysis confirms incorporation of Co(II)–Schiff base complex
with MCM-41. In another hand, the result of spectral studies exposed the mesoporous material
comprising the complex inside. Co(II) Schiff base complex functionalized on MCM-41 was utilized as
an efficient redox catalyst for 2-aminophenol synthase.
Figure: 1 Proposed structure of 2-aminophenol redox reaction mesoporous supported Co(II) Schiff base complex .
References:
1. C.Favero.;M.B.Closs.;G.B.Galland.;R.Stieler.;E.Rossetto.; K. Bernardo-Gusmão. Journal of
Catalysis 2019, 377, 63.
2. Rubiga.M.; Malathy.M.; K. Irena.; Anbarasu G.; Chozhanathmisra.M and Rajavel.R.. New J.
Chem., 2018, 42,18608.
141
P49: Turn-On Terbium Luminescence Method for Formaldehyde and Hydrogen Peroxide
Sensing
Arnab Dutta, Dipankar Bhowmik and Uday Maitra*
Department of Organic Chemistry, Indian Institute of Science, Bengaluru
Formaldehyde (HCHO) and hydrogen peroxide (H2O2) are two biologically relevant small molecules
that are, endogenously, generated and maintained at an optimum concentration via several biological
processes. Excessive concentration of HCHO and H2O2 are implicated in various diseases such as
cancer, asthma and neurodegenerative diseases.1,2
Therefore, efficient detection of these molecules
is extremely important. Lanthanides (Ln3+
) are well known for their sharp line like emission and long
excited state lifetime. However, their luminescence intensity is weak which can be attributed to the
lower value of molar extinction coefficient. From our group it has been shown that luminescence
intensity of Ln3+
can be increased substantially by doping a sensitizer molecule in the lanthanide
cholate (LnCh) hydrogel.3 Recently we have found that some functionalized aromatic compounds (Ar-
FG2 and Ar-FG4) sensitize terbium (Tb3+
) in TbCh hydrogel. We have developed a “turn-on”
luminescence method using this system to detect HCHO and H2O2. In this method, we strategically
modified the sensitizer molecules to make pro-sensitizers, Ar-FG1 and ArFG3, which do not sensitize
Tb3+
(Scheme 1). Upon reaction with the analytes, HCHO and H2O2, they produce Ar-FG2 and Ar-
FG4, respectively, resulting in a “turn-on” luminescence response. This method is found to be very
selective and sensitive, enables detection of analyte in nanomolar range. The detection method was
further simplified by using a low-cost, user-friendly paper-based approach.
Scheme 1: Scheme of representation for the detection of HCHO and H2O2 using Tb3+
luminescence
as the output signal.
References:
1. Swenberg, J. A.; Moeller, B. C.; Lu, K.; Rager, J. E.; Fry, R.; Starr, T. B. Toxicol Pathol., 2013,
41, 181.
2. Lisanti, M. P.; Martinez-Outschoorn, U. E.; Lin, Z.; Pavlides, S.; Whitaker-Menezes, D.;
Pestell, R. G.; Howell, A.; Sotgia, F. Cell Cycle, 2011, 10, 2440.
3. Bhowmik, S.; Banerjee, S.; Maitra, U. Chem. Commun., 2010, 46, 8642.
142
P50: Conformation dependent selectivity of calix[4]crown-6 ether toward metal ions
Loveleen Kaur Gulati, Gurleen Kaur Gulati, Arvind Kumar, Arun Kumar and Satish Kumar*
Department of Chemistry, St. Stephen’s College, University Enclave, Delhi-110007.
Last couple of decades have seen an increased interest in the ionophoric properties of calix[4]arenes.
1 The calix[4]arene architectures are known to exist in four different conformers called cone, 1,2-
alternate, 1,3-alternate and partial cone.1 The change in conformer causes a change in the cavity
size, which in turn produces a binding preference for a particular cationic species. A reaction between
two 1,3-alternate OH groups and polyether moiety produces a new ionophore known as calix[4]crown
ether, with better selectivity and limits the number of conformers of calix[4]arene architecture to three
(cone, 1,3-alternate and partial cone). 2 Calix[4]crown-6 ethers possess superior ionophoric properties
compared to crown ether and calix[4]arene.2 However, selectivity is still dependent on the conformers
of calix[4]arene skeleton.3, 4
Hence, it is important to investigate the conformational dependence of
ionophoric properties of calix[4]crown-6 ether. The computational methods can be an important tool to
understand and investigate the conformational properties of calix[4]crown ether along with its complex
with metal ions. Therefore, calix[4]crown-6 ether was chosen for this study and MPW1PW91
functional was used to investigate the conformations of the ether and its complex with metal ions. The
study revealed the factors affecting the stability of different conformers of calix[4]crown-6 ether along
with their selectivity towards different metal ions. H-bonds were found to play a crucial role in the
determination of stability of different conformers, while the crown ether ring size of the conformer
seemed to influence the selectivity towards a particular metal ion.
References:
1. Chawla, H. M.; Pant, N.; Kumar, S.; Kumar, N.; Black David St, C., Calixarene-based
materials for chemical sensors. In Chemical Sensors Fundamentals of Sensing Materials,
Korochenkov, G. S., Ed. Momentum Press New York: 2010; Vol. 3, p 300.
2. Chawla, H. M.; Hundal, G.; Kumar, S.; Singh, P., J. Incl. Phenom. Macrocycl. Chem. 2012,
72 (3), 323-330.
3. Chawla, H. M.; Sahu, S. N.; Shrivastava, R.; Kumar, S., Tetrahedron Lett. 2012, 53 (17),
2244-2247.
4. Greene, A. F.; Breland, D. K.; Kumar, S.; Fujiwara, T.; Webster, C. E., Abstracts of Papers,
239th ACS National Meeting, San Francisco, CA, United States, March 21-25, 2010 2010,
INOR-227.
143
P51: Synthesis and evaluation of Spiropyran-polymer conjugate
Gurleen Kaur Gulati, Loveleen Kaur Gulati, Arvind Kumar, Sojkumar dominic and Satish Kumar*
Department of Chemistry, St. Stephen’s College, University Enclave, Delhi-110007.
Last several decades have seen an intensive effort towards the development of light responsive
polymeric materials for application as sensors (for pH, temperature, ionic species), drug delivery
vehicles, photochromic lenses and storage devices.1, 2
The application of spiropyran derivatives in
such materials improves fatigue resistance, reversibility and reusability.2 Spiropyran represents a
family of photochromic molecules, which display excellent colorability and light responsive behavior
along with excellent fatigue resistance. Spiropyran derivatives are known to display two
interconvertible isomeric forms. One isomeric form of the spiropyran is colorless and nonpolar (spiro),
while the other form is polar and colored (merocyanine or MC). The two forms can be converted
reversibly to each other through application of light, heat or change in temperature. In addition,
aggregates of merocyanine form have also been reported to be induced by ionic species, which lead
to a change in color of fluorescence. The properties of spiropyran derivatives can be exploited further
through conjugation with biodegradable polymers to yield photo-switchable polymeric systems with
interesting properties, e.g., reversible nanomaterials.3, 4
Therefore, a substituted spiropyran molecule
was conjugated with a poly(L-lactide) through ring opening polymerization. The polarity difference
between the SP and MC forms was used to disrupt or produce aggregated structures. Owing to its
non-planarity, the SP form supports disruption of aggregated structure, while planar merocyanine
form supports the formation of aggregated structures. The photo-responsive polymers can thus be
used for the recognition of ionic species, which may be released through application of light. The
results of synthesis and properties of the product will be discussed.
References:
1. Mutoh, K.; Kobayashi, Y.; Abe, J., Dyes Pigm. 2017, 137, 307.
2. Sahoo, P. R.; Prakash, K.; Kumar, S., Coord. Chem. Rev. 2018, 357, 18.
3. McConnell, A. J.; Wood, C. S.; Neelakandan, P. P.; Nitschke, J. R., Chem. Rev. 2015, 115
(15), 7729.
4. Hu, J.; Zhang, G.; Ge, Z.; Liu, S., Prog. Polym. Sci. 2014, 39 (6), 1096.
144
P52: A portable and sensitive photochromic probe for Mercuric ions in water
Arvind Kumar, Ishana Kathuria, Sojkumar Dominic, Arun Kumar, and Satish Kumar*
Department of Chemistry, St. Stephen’s College, University Enclave, Delhi-110007.
The release of toxic metal ion in our environment is leading to contamination of water bodies, which
are extensively utilized by the human population to sustain lives.1, 2
Mercuric ion is among the most
toxic metal ion pollutant that affects the health of the human population and aquatic life.3 The
accumulation of mercuric ion in the marine life further aggravate the toxicity problem due to the
formation of methylmercury.4 The exposure to excessive concentration of mercuric ion leads to
disease such as Minamata disease.1 Therefore, there is a need to monitor the concentration of
mercuric ion in water. In this context, a benzothiazolium salt was synthesized having two oxygen
atoms ortho to each to bind toxic metal ions. The crystal structure of the dye displayed an extensive
network of H-bond. The structure was established through 1H,
13C-NMR, HR-MS techniques. The
probe detected the presence of mercuric ions in water by producing visible color change (pink to
colorless). The mercuric ion dis-aggregated the H-bond network of the receptor through coordination
with oxygen atoms present in the molecule. Test strips loaded with receptor were developed which
could be used for field applications for mercuric ions monitoring in water. Density functional theory
calculations were also performed to further investigate the mechanism of the complex formation,
which indicated that one molecule of the probe binds one molecule of mercuric ion and supported
Job‟s plot data. The TD-DFT studies further suggested the disappearance of color by indicating an
increase in the HOMO-LUMO gap in the complex compared to the HOMO-LUMO gap in the
benzothiazolium dye based probe.
References:
1. Spiegel, S. J., Lancet 2017, 390 (10091), 226-227.
2. Kumar, A.; Sahoo, P. R.; Arora, P.; Kumar, S., J. Photochem. Photobiol. A 2019, 384,
112061.
3. Sahoo, P. R.; Prakash, K.; Kumar, S., Coord. Chem. Rev. 2018, 357, 18-49.
4. Okpala, C. O. R.; Sardo, G.; Vitale, S.; Bono, G.; Arukwe, A., Crit. Rev. Food Sci. Nutr.
2018, 58 (12), 1986-2001.
145
P53: Homoleptic zinc-catalyzed hydroboration of aldehydes and ketones in presence of HBpin.
Gobbilla Sai Kumar, Adimulam Harinath, Rajrani Kawaria and Tarun K Panda*
Department of Chemistry, Indian Institute of Technology, Hyderabad Kandi-502285, Sangareddy, Telangana, India. In recent decade, hydroboration of aldehyde or ketones in presence of catalyst has been keen
interest for the synthesis of organic molecules.1 Boronate ester compounds are preferred over other
organometallic reagents owing to their nontoxicity and stability.2 Hence, a wide range of metal
catalysts have been used in the hydroboration of various unsaturated moieties, including alkenes,
alkynes, imines, nitriles, and carbonyl compounds.3,4
Here, we report the reaction between N-phenyl-
O-phenyl-enediamine and pyrrole-2-carboxyaldehyde to afford the N-phenyl-O-phenyl-
enediiminepyrolyl ligand {L-H2} in quantitative yield. A one-pot reaction between {L-H2} and
diethylzinc (ZnEt2) in a 2:1 ratio afforded the homoleptic zinc metal complex [{L-H}2Zn] (1). The solid-
state structures of ligand {L-H2} and zinc complex 1 were confirmed using X-ray crystallography.
Further, complex 1 was used for chemoselective hydroboration of aldehydes and ketones in the
presence of pinacolborane (HBpin) at ambient temperature to produce the corresponding boronate
esters in high yield.
Figure 1: Schematic representation for hydroboration of aldehyde or ketones in presence of
homoleptic zinc metal complex 1.
References:
1. Lennox, A. J.; Lloyd-Jones, G. C. Chem. Soc. Rev. 2014, 43, 412.
2. Carroll, A. -M.; O'Sullivan, T. P.; Guiry, P. J.; Adv. Synth. Catal. 2005, 347, 609.
3. (a) Wen, H.; Liu, G.; Huang, Z. Coord. Chem. Rev. 2019, 386, 138; b) Zhang, L.; Peng, D.;
Leng, X.; Huang, Z. Angew. Chem. Int. Ed. 2013, 52, 3676.
4. a) Harinath, A.; Bhattacharjee, J.; Gorantla, K. R.; Mallik, B. S.; Panda, T. K. Eur. J. Org. Chem.
2018, 24, 3180.; b) Harinath, A.; Bhattacharjee, J.; Nayek, H. P.; Panda, T. K. Dalton trans.
2018, 47, 12613. c) Harinath, A.; Banerjee, I.; Bhattacharjee, J.; Panda, T. K. New J.
Chem. 2019, 43, 10531.
146
P54: Efficient and Chemoselective Hydroboration of Organic Nitriles by TiIV
Catalyst Supported
by Unsymmetrical Acenaphthenequinonediimine Ligand
Indrani Banerjee, Srinivas Anga, Kulsum Bano, and Tarun K. Panda*
Department of Chemistry, Indian Institute of Technology, Hyderabad Kandi-502285, Sangareddy, Telangana, India.
Recent trends in synthetic chemistry demonstrate the growth in use of synthetic methods in
multicomponent reactions and catalysis using earth-abundant metals. Titanium being the second-
most abundant and non-toxic metal on earth has been used as a preeminent catalyst in widespread
applications.1 In recent years, synthetic chemists find organoboron compounds advantageous as they
are easy to handle and are atom efficient. Over the past few years, numerous methods have been
reported on the hydroboration of nitriles using transition metals and alkaline metals.2 We recently
reported a number of Ti(IV) amido complexes and found that these complexes indeed support various
catalytic reactions under ambient conditions.3 Herein, we discussed the synthesis, characterization,
and utilization of a titanium (IV) complex (1) supported by a monoanionic ligand as a pre-catalyst for
the hydroboration of nitriles to afford diboryl amines.4 Complex 1 exhibited high conversion, superior
selectivity, and broad functional group tolerance during hydroboration of nitriles with both HBpin and
HBcat under mild conditions.
Figure 1. Ti(IV) catalysed hydroboration of organic nitriles.
References:
1. (a) Odom, A. L.; McDaniel, T. J. Acc. Chem. Res. 2015, 48, 2822. (b) Yun, J.;
Buchwald, S. L. J. Am. Chem. Soc. 1999, 121, 5640.
2. (a) Kaithal, A.; Chatterjee, B.; Gunanathan, C. J. Org. Chem. 2016, 81, 11153. (b)
Weetman, C.; Anker, M. D.; Arrowsmith, M.; Hill, M. S.; Kociok-Köhn, G.; Liptrota, D. J.;
Mahon, M. F. Chem. Sci. 2016, 7, 628.
3. (a) Bhattacharjee, J.; Das, S.; Kottalanka, R. K.; Panda. T. K. Dalton Trans, 2016, 45, 17824.
(b) Naktode, K.; Das, S.; Bhattacharjee, J.; Nayek, H. P.; Panda, T. K. Inorg. Chem. 2016, 55,
1142
4. Banerjee, I.; Anga, S.; Bano, K.; Panda. T. K. J. Organomet. Chem. 2019, 902, 120958.
147
P55: Ruthenium catalyzed N-alkylation of amines with alcohols via barrowing hydrogen
methodology
Sekar Gayathri, Periasamy Viswanathamurthi
Department of Chemistry, Periyar University, Salem - 636011
The catalytic construction of C−N bonds via borrowing hydrogen methodology [1], have recently
received much attention since nitrogen functionalities occur in various compounds of synthetic and
pharmaceutical significance as well as in important biologically active molecules. In contrast with
other transition-metal-catalyzed methodologies, e.g., amination of organohalides (Buchwald-Hartwig
amination), reductive amination of carbonyl compounds, hydroamination and hydroaminomethylation
of carbon-carbon unsaturated compounds, etc., the N-alkylation of amines with alcohols, produced
water as the sole by-product, may serve as a relatively green and environmentally benign alternative.
Moreover the use of alcohols as the alkylating agent is direct and simple as the alcohols are readily
available, highly stable, low in toxicity, easily stored and handled, low in cost, and relatively high in
atom efficiency. Several ruthenium complexes containing phosphine ligands have been employed in
the N-alkylation of amines with alcohols in good yields and selectivity [2]. However, they are not
trouble free as most of the methods reported have some difficulties like the requirement of high
temperature, pressure and prolonged reaction times up to a few days. The drawbacks to the reported
catalysts necessitate the synthesis of new catalysts. Hence, new ruthenium catalysts have been
designed, synthesized and characterized by analytical and spectroscopic (IR, UV-Vis, 1H &
13C NMR,
ESI-Mass and single crystal X-ray crystallography) techniques. The catalytic property of the new
complexes was screened for N-alkylation of amines with alcohols under optimized conditions. The
role of co-ligands in determining the catalytic activity for N-alkylation was also investigated.
References:
1. R. Ramachandran, G. Prakash, S. Selvamurugan, P. Viswanathamurthi, J. G. Malecki, V.
Ramkumar. Dalton Trans. 43 (2014) 7889.
2. R. Ramachandran, G. Prakash, S. Selvamurugan, P. Viswanathamurthi, J. G. Malecki, W.
Linert, A. Gusev, RSC Adv. 5 (2015) 11405.
148
P56: Microwave-Assisted the Suzuki-Miyaura Cross Coupling Reaction Using Ni-Complex
Functionalized MCM-41 as an Efficient and Reusable Heterogeneous Catalyst
M. Bharathi, S. Indira, G. Vinoth and K. Shanmuga Bharathi*
Department of Chemistry, Periyar University, Salem - 636011
A new Ni-Schiff-Base Complex-bipy on MCM-41 was prepared. The prepared compound has been
extensively characterized by FT-IR, UV-DRS, Small angle-XRD, SEM-EDX, BET, ICP-OES and TEM
analysis. Suzuki-Miyaura cross-coupling reaction for the Synthesis of biaryl derivatives was carried
out under microwave irradiation using Ni-Complex-bipy-MCM-41 as an efficient catalyst. Microwave
energy was employed to obtain the desired products in excellent yields (~95 %). Notably, Catalyst
was recovered by simple filtration method and reused up to four cycles without any significant loss in
the yield. Moreover, the yields of the products are much increased while using Ni-MCM-41 complex
as catalyst instead of using pure MCM-41 and Ni-Complex.
References:
1. Dhara, K; Sarkar, K; Srimani, D; Kumar Saha, S; Chattopadhyay, P; Bhaumik, A. Dalton
Trans. 2010, 39, 6395.
2. Vinoth, G; Indira, S; Bharathi, M; Nandhakumar, A; Sathishkumar, K; Shanmuga Bharathi, K.
J.Coord. Chem. 2019, 71, 3934.
149
P57: A bisphenol based fluorescence chemosensor for the sequential detection of Zn2+
and
PPi ions and its bioluminescence imaging
Rajasekaran Dhivya, Perisamy Viswanathamurthi*
Department of Chemistry, Periyar University, Salem - 636011
The design and development of chemosensors have expanded substantially in last few decades.
Synthesis of new chemosensors for detection of transition metals including heavy metal ions have
been of great interest for chemists, in recent years as they play important roles in the areas of
chemical, biological and environmental systems.1 Fluorescent sensor technology has attracted
considerable attention as a type of facile and efficient detection method for sensing biological
and chemical species because of their simplicity, versatility, high selectivity and sensitivity. Based on
the above-mentioned premise, herein we report the synthesis of bisphenol based Schiff base
chemosensor (L). The new fluorescent chemosensor (L) exhibits sequential detection of Zn2+
and
pyrophosphate (PPi) anion in mixed buffer solution at physiological pH.2 The probe exhibits turn-on
fluorescence response with the addition of Zn2+
ions even as low as 1 nM. Further, addition of
pyrophosphate anion led to quenching of fluorescence activity of L-Zn2+
ensemble. In addition, the
sensitive fluorescence probe (L) has been utilized as a powerful tracker for zinc and pyrophosphate
ion in biological systems.
References:
1. Song, T; Cao, Y; Zhao. G; Pu, L. Inorg. Chem. 2017, 56, 4395.
2. Wang, J; Lin, W; Li, W Chem. Eur. J. 2012, 18, 13629.
150
P58: Single luminescent chemosensor for the discriminative detection of mercury ion in
environment and its application on live cell imaging
Venkatachalam Kavitha, Periasamy Viswanathamurthi*
Department of Chemistry, Periyar University, Salem - 636011
Mercury (II) is one of the environmentally most important cations whose toxicity has long been
recognized as a permeating environmental problem, because marine aquatic organisms convert
inorganic mercury Hg2+
into neurotoxic methyl mercury which bioaccumulates to the human body and
in other organisms through propagation in the food chain. This bioaccumulated mercury in living
organisms leads to adverse impacts on nervous systems, brain, kidney and many cognitive diseases
like minamata disease and alzheimer‟s disease to human body. Hence, selective recognition of such
harmful metal ions at its submicromolar level for biological, environmental, ecological, and medicinal
purposes is extremely beneficial as well as essential. Several conventional techniques such as
electrochemical method, spectroscopy, chromatography etc ., have been used but all this methods
are lacking from practical consequences.1 Therefore, the recent researches were focusing on
chemical sensor technique to detect the mercury ion because of its advantages like sensitivity,
selectivity, real time, rapid response, non-invasive and non-destructive properties.2 Based on all, in
this work a novel bisphenol A based probe having fascinating spectral properties have been designed
and synthesized for the selective detection of mercury ion in environment and biological systems even
in nanomolar level concentration. The probe is also utilized to detect mercury ion in realistic samples.
References:
1. Chen, Y; Wang, X; Yang, X. F; Zhong, Y; Li, Z; Li, Z. Sens. Actuator B- Chem. 2015, 206,
268.
2. Cheng, C. C; Chen, Z. S; Wu, C. Y; Lin, C. C; Yang, C. R; Yen, Y. P. Sens. Actuators B-
Chem. 2009, 142, 280.
151
P59: Synthesis, characterisation and antibacterial activity of 1,2,3 triazoles.
Anis Ahmed Sheikh1, Syed Ummul Khair Asema
1, Shaukat Patel Karimkha
2, Sayyad Sultan Kasim
1*
1Department of Chemistry, Maulana Azad College of Arts, Science & Commerce, Aurangabad.
431001. MS. India. 2Adarsh Senior College, Omerga, 413606 District Osmanabad. MS. India.
1,2,3 triazoles are important nitrogen heterocyclic compounds having diverse biological applications in
medicinal chemistry. In spite of their vital applications in medicinal field these compounds are also
more advantageous in agriculture and organic synthesis. The simple synthesis of these compounds
through “Click reaction” and good yield attracts the much attention of researchers towards these
fruitful compounds. In this research work we have synthesised the 1,4 disubstituted 1,2,3 triazoles
derivatives through click reaction and characterised by 1HNMR, Mass and IR data. These synthesized
compounds were evaluated for antibacterial activity against Bacillus substillus, Escherichia coli and
Staphylococcus aureus. The results obtained are tabulated. The antibacterial results revealed that
majority of compounds exhibits good activity against the selected strains. The substituent on triazole
nucleus also plays an important role in antibacterial activity.
O N3
ON
NN
R1
R2
R3
R4
R5 R1
R2
R3
R4
R5
Click Reaction
10 Examples Synthesis of 1,4 disubstituted 1,2,3 triazoles
References:
1. Kolb, H.C., Finn, M.G., Sharpless, K.B. Angew. Chem. Int. Ed. 2004, 40.
2. Celik, F., Unver, Y., Barut, B., Ozel, A., Sancak, K. Medicinal Chemistry. 2018, 3. 230.
3. Alvarez, B.J.,Vaquero, J.J., Barluenga, J. Modern heterocyclic Chemistry, 2011, 2. Wiley,
Weinheim, 989.
4. Kamal, A., Shankaraiah, N., Devaiah, V. Bioorg. Med. Chem. Lett. 2008. 18, 1468.
152
P60: Cu(I)-Catalyzed Ligand-free Tandem One Pot or Sequential Annulation via Knoevenagel
Intermediate: An Entry into Multifunctional Naphthalenes, Phenanthrenes and Quinolines
Adula Kalyani, Rajnikanth Sunke and K. C. Kumara Swamy*
School of Chemistry, University of Hyderabad, Hyderabad 500 046, Telangana, India.
Polysubstituted carbocycles/ heterocycles have widespread applications in pharmaceutical and
agrochemical fields.1-2
Copper catalyzed coupling reactions are well-known, but their application for
the synthesis of polysubstituted carbocycles/ heterocycles is rather limited.3-4
We have developed a
simple and efficient methodology for the construction of multifunctional naphthalenes, phenanthrenes
and quinolines through o-bromoaromatic aldehydes and nitriles/esters containing an active methylene
group via Knoevenagel condensation, C-arylation and decarboxylation followed by aromatization/
cyclization via copper-catalysis, all in one pot.5 The prepared phenanthrenes compounds are
fluorescence active.
References:
1. Xu, X.; Shang, R.; Cai, Z.; Zhao, X. Phys. Chem. Chem. Phys. 2009, 11, 8560.
2. Koppanathi, N.; Kumara Swamy, K. C. Org. Biomol. Chem. 2016, 14, 5079.
3. (a) Ma, D.; Cai, Q. Acc. Chem. Res. 2008, 41, 1450. (b) K. Kunz, U. Scholz, D. Ganzer,
Synlett, 2003, 2428.
4. Panda, N.; Mothkuri, R.; Pal, A.; Paital, A. R. Adv. Synth. Catal. 2013, 255, 2809.
5. Sunke, R. Kalyani, A. Kumara Swamy K. C. J. Org. Chem. 2020, 0000 (Just accepted).
153
P61: APPLICATIONS OF LUMINESCENT LANTHANIDE HYDROGELS IN AMINE VAPOR
SENSING
Dipankar Bhowmik, Mitasree Maity and Uday Maitra*
Department of Organic Chemistry, Indian Institute of Science, Bengaluru
“Luminescent” lanthanides have intrinsically low molar absorption coefficients, but this problem can be
addressed by complexing the lanthanide ions with suitable chelating ligands which improve the
luminescence properties drastically.1 A simpler way to sensitize lanthanides which avoids laborious
synthetic steps has been developed in our group. This involved the doping of 2,3-
dihydroxynaphthalene (DHN) in terbium cholate, and pyrene in europium cholate hydrogels which
resulted in significantly enhanced luminescence.2,3
Our recent studies revealed that several biphenyl
derivatives could also sensitize Tb(III) in terbium cholate hydrogels. We have used such as system for
developing a luminescence turn-off response for detecting hazardous amine vapors.4 When terbium
cholate gel doped with a biphenyl derivative was exposed to various amine vapors, luminescence
quenching was observed. Interestingly, the quenching was selective to amine and nitro compounds
only.2 Appreciable quenching was observed even at low ppm levels of the analytes. We have
simplified this detection method by using a low-cost, user-friendly paper based approach for easy
detection of the analytes.
Scheme: Sensitization of Tb(III) and Eu (III) luminescence in the presence of micro-molar
concentration of sensitizer.
References:
1. Bünzli, J.C.; Piguet, C. Chem. Soc. Rev. 2005, 34, 1048.
2. Kandanelli, R.; Sarkar, A.; Maitra, U. Dalton Trans. 2013, 42, 15381.
3. Banerjee, S.; Kandanelli, R.; Bhowmik, S.; Maitra, U. Soft Matter. 2011, 7, 8207.
4. Shen, X.; Yan, B. J. Mater. Chem. C. 2015, 3, 7038.
154
P62: Low cost paper based sensors for (bio) analyte sensing using terbium
photoluminescence
Shruthi Sakthivel, Tumpa Gorai and Uday Maitra*
Department of Organic Chemistry, Indian Institute of Science, Bengaluru
Efficient methods for the rapid detection of (bio) analytes are in great demand. In this direction, paper
based sensors have attracted attention for their low cost, biocompatibility, biodegradability and easy
availability.1
In the recent years, lanthanide ions have been extensively used as probes in various
detection systems due to their long excited lifetimes and sharp almost line like emission. However,
they have low emission intensities due to their intrinsic low molar absorptivities.2 Our group has
addressed this problem by simply doping an appropriate organic molecule in a lanthanide cholate gel
matrix, which improved their luminescence property drastically. For instance, doping micromolar
concentration of 2,3-dihydroxy naphthalene (DHN) in terbium cholate (TbCh) hydrogel resulted in
enhanced luminescence.3 Recently, we discovered that gallic acid and its esters could also sensitize
Tb (III) similarly in TbCh gel. We have used such sensitized luminescence in developing a simple
strategy involving a luminescence turn-on response for the rapid detection of gallate derived
antioxidants in green tea extracts and a biologically important enzyme - β-glucuronidase (scheme A).
TbCh gel coated paper discs4 showed linear luminescence response with the increasing addition of
gallate derived moieties. Therefore, these gel coated paper discs were used for the detection of total
gallated polyphenol content in various green tea samples with good selectivity and sensitivity. On the
other hand, DHN was suitably modified with a sugar unit such that the free sensitizer was released
upon the action of β-glucuronidase resulting in enhanced green emission. This enzyme detection
method showed good selectivity in the presence of other enzymes and detection limits in nanomolar
range. Overall, this method serves as an efficient tool for the easy detection of analytes in various
natural and biological samples without interferences from autofluorescence of the samples.
Scheme A: TbCh gel coated paper discs for analyte sensing. References:
1. Yetisen, A. K.; Akram, M. S.; Lowe, C. R. Lab on a Chip. 2013, 13, 2210.
2. Bünzli, J. C. G. Chem. Rev. 2010, 110, 2729.
3. Banerjee, S.; Kandanelli, R.; Bhowmik, S.; Maitra, U. Soft Matter 2011, 7, 8207.
4. Gorai, T.; Maitra, U. ACS Sensors 2016, 1, 934.
155
P63: Biogenic ZnO NPs: TL emission and direct sunlight assisted selective photodegradation of
cationic dyes
Anupama R Prasad, Shamsheera K O, Julia Garvasis and Abraham Joseph*
Department of Chemistry, University of Calicut, Calicut University P O, Kerala, India
Nano Zinc Oxide (ZnO NPs) is a popular photocatalyst and versatile semiconducting material for
energy, environmental and biomedical applications [1-3]. Herein, we have developed ZnO
nanoparticles via Abelmoschus esculentus (okra) mucilage assisted green strategy without employing
additional solvents or stabilizers. The nanoaprticles obtained with good crystallinity and purity with
average size of 70 nm with variable morphology. The optical band gap was determined to be 3.12 eV.
Thermoluminescence (TL) emission was monitored with variable dosage of gamma radiation. The
photodegradation of the material was investigated under direct sunlight and UV light irradiation with a
set of organic dyes. A selective degradation of cationic dyes Methylene Blue (MB) and Rhodamine B
(RhB) has been observed due to the negative surface charge of ZnO catalyst (-38.37 eV). The dyes
were completely removed from their aqueous solutions within 35-40 minutes under direct sunlight and
the catalyst was more active under the sunlight than UV light irradiation. The scavenger effects were
immensely perceptible for molecular oxygen>electrons> holes. The catalyst was recovered and
reused for four consecutive cycles retaining remarkable degradation efficiency.
Fig 1.
References:
1. Anupama, R. P.; P. Rugmini, A.; Joseph, A. Matter. Res. Bull. 2018, 102, 116-121.
2. Anupama, R. P.; Sabeel, M. B.; Linda, W.; Joseph, A. Int. J. Biol. Maromol. 2019, 139, 712 -
718.
3. Bala, N.;Saha, S.;Chakraborty, M.; Maiti,M.;Das, S.; Basu, R.;Nandy, P. RSC Adv. 2015, 5,
4993–5003.
156
P64: Structural elaboration of 1H-indole-2,3-dione and its evaluation as potent agrochemicals
Komalpreet Kaur, Lovepreet Kaur, Samita and Divya Utreja
Department of Chemistry, Punjab Agricultural University, Ludhiana, Punjab-141004
1H-Indole-2,3-dione or isatin and its derivatives are the prominent N-heterocyclic bioisosteres due to
their intrinsic versatility they poised them as true cornerstones in pharmaceutical and agricultural
industry. They are the perfect tail for design and development of promising plant growth regulators,
herbicides, fungicides, antibacterial agents etc. Regioselective elaboration of isatin at N-1 and C-3
poisitions were carried out using phase transfer catalyst- Tetrabutyl ammonium hydrogen sulfate
(TBAHS) and Grignard reagents respectively. The synthesized compounds were characterized using
various spectral techniques. Isatin and its derivatives were evaluated as antinemic, antimicrobial and
antioxidant agents. The biological screening of compounds identified them as true drugs with
remarkable activity and selectivity. Further, the compounds were subjected to structure activity
relationship studies through various in silico studies. Therefore, studies have been carried out for
synthesis and designing of new drugs in pharmaceutical and agricultural industry.
References:
1. Singh, G. S.; Desta, Z. Y. Isatins as privileged molecules in design and synthesis of Spiro-
fused cyclic frameworks. Chem. Rev., 2012, 112, 6104.
2. Moradi, R.; Ziarani, G.M.; Lashgiri, N. Recent applications of isatin in the synthesis of organic
compounds. Arkivoc, 2017, 1, 148.
157
P65: Fe/Fe3O4@Covalent Organic Framework as Lightweight Nanomagnets
Kaleeswaran D,a Rinku Kushwaha,
a, b Sattwick Haldar,
a, b Debanjan Chakraborty,
a, b Dinesh Mullangi,
a,
bAditya Borah,
c Ramaswamy Murugavel
c and Ramanathan Vaidhyanathan
a, b
a Department of Chemistry, Indian Institute of Science Education and Research, Pune, 411008 India.
bCentre for Energy Science, Indian Institute of Science Education and Research, Pune, 411008 India
c Department of Chemistry, Indian Institute of Technology Bombay, Mumbai, 400076 India.
Two dimensional (2D) Covalent Organic Frameworks (COFs) are made of light atoms such as C, N,
O, B and H with significant void/framework ratio, this makes them excellent low-density supports for
various metal nanoparticles. 1 Their ordered one dimensional (1D) pores offer high surface area
favoring uniform dispersion of the magnetic nanoparticles like Fe3O4 and Co/Co(OH)2 without
conceding their intrinsic property.2 The organic nature of such composite facilitate their amalgamation
with bulk materials such as paper/textile to enable lightweight nanomagnetic materials which carry
potential in several defense and next-generation aviation applications.
References:
1. (a) Kaleeswaran, D.; Antony, R.; Sharma, A.; Malani, A.; Murugavel, R., ChemPlusChem
2017, 82, 1253; (b) Chakraborty, D.; Nandi, S.; Mullangi, D.; Haldar, S.; Vinod, C. P.;
Vaidhyanathan, R., ACS Appl. Mater. Interfaces 2019, 11, 15670; (c) Chakraborty, D.; Nandi,
S.; Illathvalappil, R.; Mullangi, D.; Maity, R.; Singh, S. K.; Haldar, S.; Vinod, C. P.; Kurungot,
S.; Vaidhyanathan, R., ACS Omega 2019, 4, 13465.
2. (a) Li, Y.; Yang, C.-X.; Yan, X.-P., Chem. Commun. 2017, 53, 2511; (b) Mullangi, D.;
Chakraborty, D.; Pradeep, A.; Koshti, V.; Vinod, C. P.; Panja, S.; Nair, S.; Vaidhyanathan,
R., Small 2018, 14, 180.
158
P66: The Halogen Bond: An Efficient Tool for Electron Catalyzed C-I and C-S Bond Formation
at Room Temperature
Anuradha Nandy, G. Sekar*
Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
Halogen bond (XB) refers to the attractive noncovalent interactions between terminal halogen atoms
in compounds of the type R-X (X = Cl, Br, I; R = electron withdrawing group) and Lewis bases (LB).1
Recently, we have developed new XB donor catalysts for several transition metal-free organic
reactions where halogen-bonded halogen(I) species act as key intermediates with unusual reactivity
and selectivity.2 For the first time, the halogen-bond has been employed as an efficient tool to enable
an electron-catalyzed regioselective iodination of hetero-aryls under mild reaction conditions.3 The
halogen bond between hetero-aryl substrates (electron-donor) and iodine (electron-acceptor) lowers
the activation energy of the electron-transfer (ET) from the former to the latter.4
Taking this
methodology a step further, a one pot synthesis of heteroaryl thioethers has been carried out under
visible light condition.5
The formation of halogen bond and the regioselectivity of the reaction have
been demonstrated with several control experiments, spectroscopic analysis and quantum chemical
calculations.
Scheme 1. XB-assisted visible light driven C-S bond formation of various heteroarenes at room
temperature.
References:
1. a) Desiraju, G. R.; Ho, P. S.; Kloo, L.; Legon, A. C.; Marquardt, R.; Metrangolo, P.; Politzer, P.;
Resnati, G.; Rissanen, K. Pure Appl. Chem. 2013, 85, 1711.
2. a) Kazi, I.; Guha, S.; Sekar, G. Org. Lett. 2017, 19, 1244. b) Guha, S.; Kazi, I.; Mukherjee, P.;
Sekar, G. Chem. Commun. 2017, 53, 10942. c) Guha, S.; Kazi, I.; Nandy, A.; Sekar, G. Eur. J.
Org. Chem. 2017, 5497.
3. Kazi, I.; Guha, S.; Sekar, G. J. Org. Chem. 2019, 84, 6642.
4. Rosokha, S. V.; Vinakos, M. K. Phys.Chem.Chem.Phys. 2014, 16, 1809.
5. Nandy, A.; Kazi, I; Guha, S.; Sekar, G. (Manuscript submitted).
159
P67: Chemoenzymatic Approach gives New Insight into Rugulosin Biosynthesis
Nirmal Saha, Syed Masood Husain*.
Molecular Synthesis and Drug Discovery Unit, Centre of Biomedical Research SGPGIMS Campus,
Raebareli Road, Lucknow 226014 (India)
Modified bisanthraquinone, (–)-rugulosin (1) isolated first from P. Islandicum Sopp[2]
is a complex
dimeric natural product with diverse biological activities.[1]
Early studies using feeding experiments
has established emodin (2) as a biosynthetic precursor for (–)-rugulosin biosynthesis along with
several proposed intermediates. In recent years, we have developed a chemoenzymatic, biomimetic
strategy to synthesize (–)-rugulosin (1) in three steps starting from emodin (1). This has also resulted
in the isolation and characterization of many putative biosynthetic intermediates such as 3,4-
dihydroemodin (3), (–)-flavoskyrin (4) and a dimeric intermediate 5 which gives further insight into the
biosynthesis of (–)-rugulosin (1). For the first time, the 3,4-dihydroemodin (3) is obtained by the
oxidation of a reduced emodin hydroquinones synthesized by the reduction of emodin (2) catalyzed
by an NADPH dependent anthrol reductasefrom Talaromyces islandicus (ARti) in the presence of
Na2S2O4.[3]
In addition, we have synthesized intermediate 5 using (–)-flavoskyrin (4) obtained through
dimerization of 3,4-dihydroemodin (3). Finally, the conversion of 4 into (–)-rugulosin (1) via putative
biosynthetic intermediates supports its role in the newly proposed biosynthetic pathway. The study
presented here will provide vital clues for the biosynthesis of related bisanthraquinones isolated from
fungi in future.
References:
1. Nakamura, S.; Nii, F.; Shimizu, M.; Watanab, I. Japan. J. Microbiol. 1971,15, 113-120.
2. Seo, S.; Ogihara, Y.; Sankawa, U.; Shibata, S. Tetrahedron Lett. 1972, 13, 735-736.
3. Singh, S. K.; Mondal, A.; Saha, N.; Husain, S.M. Green Chem., 2019,21, 6594-6599.
160
P68: Novel Iron Chelators for the Treatment of Alzheimer‟s Disease
P. Duraippandi†#
, Zhixuan Wu†, Nady Braidy
§, Nor Hawani Salikin
&, Suhelen Egan
&, Michael L. H.
Huang†, and Des R. Richardson
†*
†Department of Pathology, The University of Sydney, Sydney, New South Wales, 2006, Australia.
§School of Psychiatry, University of New South Wales, Sydney, 2031, Australia. &Centre for Marine Science and Innovation, University of New South Wales, Sydney, 2031, Australia.
#Department of Chemistry, Central University of Karnataka, Gulbarga-585367, India.
Alzheimer‟s disease (AD) is a multi-factorial condition that leads to cognitive decline and represents a
major global health challenge in ageing populations.1 The lack of effective AD therapeutics led us to
develop multi-functional nicotinoyl hydrazones2 to target multiple pathological AD hallmarks. The most
active analogue among 20 is 6-methoxysalicylaldehyde nicotinoyl hydrazone (SNH6) which
demonstrated: (1) low cytotoxicity; (2) potent iron (Fe)-chelation efficacy; (3) significant inhibition of
copper-mediated Aβ aggregation; (4) oxidative stress alleviation; (5) effective donation of NAD+ to
NAD-dependent metabolic processes (PARP and sirtuin activity) and enhanced cellular NAD+ /NADH
ratios, as well as significantly increased median C. elegans lifespan (1.46-fold of the control); (6)
partially decreased BACE1 expression, resulting in significantly lower soluble amyloid precursor
protein-β (sAPPβ) and Aβ 1-40 levels; and (7) favourable blood-brain barrier-permeation properties
(Scheme 1). Structure-activity relationships demonstrated the ability of our nicotinoyl hydrazones to
increase NAD+ was dependent on the electron-withdrawing or -donating substituents on the aldehyde-
or ketone-derived moiety. Aldehyde-derived hydrazones containing the ONO-donor set and electron-
donating groups were required for NAD+-donation and low cytotoxicity. This study highlighted the
potential of nicotinoyl hydrazones, particularly SNH6, to act as multi-functional therapeutics and
delivery vehicles for NAD+-precursors for AD treatment.
Scheme 1: Multifunctional activity of SNH6 to Alzheimer‟s disease.
References:
1. LaFerla, F. M.; Oddo S. Trends Mol. Med. 2005, 11, 170.
2. Kalinowski, D.S.; Richardson D. R. Pharmacol. Rev. 2005, 57, 547.
Lifespan BACE1 Aβ
Cu-mediated Aβ
aggregation
SNH6
ROS
NAD+/NADH
High Fe
chelation
efficacy
161
P69: Cu-Catalyzed One-pot Synthesis of Thiochromeno-quinolinone and Thiochromeno-
thiochromenone via Double Hetero Michael Addition Using In-situ Generated Nucleophiles
N.Sundaravelu and G.Sekar*
Department of chemistry, Indian Institute of Technology Madras, Chennai, Tamilnadu-600036, India
4-Quinolone has been well recognized as a privileged scaffold prevalent in a vast array of natural
products and biologically active compounds.1 Although the aforementioned methods provided
effective synthetic routes to a wide variety of 4-quinolones, 2
the use of expensive catalysts or pre-
functionalized starting materials, which often require multi-steps preparation and waste halogen by-
products have limited their applications to some extent. As part of our ongoing research towards Cu-
catalyzed in-situ generation of thiol using xanthate as sulfur surrogate,3 a copper catalyzed one-pot
synthesis of thiochromeno[4,3-b]quinolin-7-one via double hetero Michael addition using in-situ
generated sulfur followed by aza nucleophiles has been reported.4 Further, this method was extended
for the synthesis of thiochromeno[4,3-b]thiochromen-7-one via intermolecular followed by
intramolecular sulfa-Michael addition. This reaction proceeds through thiolate formation/intermolecular
sulfa-Michael addition/ aldol condensation/reduction of nitro group via PCET pathway/aza-Michael
addition/further this will be oxidized by in-situ generated iodine from waste by product KI.
Experimental studies proved that the nitro group reduction takes place via PCET and in-situ
generated iodine plays a key role in the oxidation step.
Scheme: Cu-catalyzed one-pot synthesis of thiochromeno-quinolinone and thiochromeno-
thiochromenone via double hetero Michael addition
References:
1. Huse, H.; Whiteley, M. Chem. Rev. 2011, 111, 152.
2. Ma, Y.; Zhu, Y.; Zhang, D.; Meng, Y.; Tang, T.; Wang, K.; Ma, J.; Wang, J.; Sun, P. Green
Chem. 2019, 21, 478.
3. Sundaravelu, N.; Sekar, G. Org. Lett. 2019, 21, 6648.
4. Sundaravelu, N.; Sekar, G (manuscript under preparation)
162
P70: Remodelling of Aβ Aggregation by CDP Peptidomimetics Inhibitors
Mouli Konar, Debasis Ghosh, Sourav Samanta and Thimmaiah Govindaraju* Bioorganic Chemistry Laboratory, New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru 560064, Karnataka, India
Alzheimer's disease (AD) is a major neurodegenerative disorder for which currently there are no diagnosis
or treatment. Accumulation of amyloid plagues in the brain and their multifaceted toxicity is considered as
pathological hallmarks of AD. Amyloid-β (Aβ) peptides undergo aggregation mainly thr
structure supported by hydrophobic interactions of the core recognition region HQKLVFFAED (Aβ14-23).
Disruption of the hydrogen bonding interactions within the β-sheet structure (Aβ42 fibrils) is one the
potential routes to inhibit their formation and growth. In this context, we sought to design a new class of
peptidomimetics having multiple donor-accepter sites. Our preliminary work showed that cyclic
dipeptide (CDP)-based unnatural amino acid (kd) with multiple hydrogen bond donors and acceptors
indeed capable of modulating the aggregation process Aβ14-23 albeit over a prolonged period of
incubation. Subsequently, kd was incorporated into Aβ14-23 at predetermined positions and the derived
CDP-peptidomimetics were found to effectively modulated the fibrillation process of Aβ14-23 when
monitored at two pH (2 and 7.4) conditions. A detailed biophysical study indicated that the conformational
transition (between random coil to β-sheet via α-helix) of Aβ14-23 is restricted to α-helical conformation at
pH 7.4 in the CDP-peptidomimetics which control the growth of nucleated intermediates to inhibit the toxic
aggregation species. These result encouraged us to investigate the effect of CDP-peptidomimetics on the
aggregation propensity of Aβ42 peptide and it has been found that the CDP-peptidomimetics act as good
inhibitors of Aβ42 fibrillation under physiological conditions. Further, in cellulo results were found to be in
good agreement with the in vitro studies. Overall, these results hold significant promise towards the
advancement of our understanding of the AD pathology and development of potential therapeutics.
References:
1. Rajasekhar, K.; Chakrabarti, M.; Govindaraju, T. Chem. Commun. 2015, 51, 13434.
2. Knowles, T. P. J.; Vendruscolo, M.; Dobson, C. M. Nature Rev. Mol. Cell Biol. 2014, 15, 384..
3. Madhu, C.; Voshavar, C.; Rajasekhar, K.; Govindaraju, T. Org. Biomol. Chem. 2017, 15,
3170.
4. Manchineella, S.; Govindaraju, T. Chempluschem. 2017, 82, 88.
5. Rajasekhar, K.; Madhu, C.; Govindaraju, T. ACS Chem. Neurosci. 2016, 7, 1300.
6. Rajasekhar, K.; Narayanaswamy, N.; Mishra, P.; Suresh, S. N.; Manjithaya, R.; Govindaraju, T.
ChemPlusChem. 2014, 79, 25.
7. S. Samanta, K. Rajasekhar, V. Babagond, T. Govindaraju, ACS Chem. Neurosci. 2019, 10,
3611.
163
P71: Open Chain Pyrrole Based Ligands and Their Coordination Complexes
Sabari Panchavarnam, Kishor G. Thorat and Mangalampalli Ravikanth*
Department of Chemistry, Indian Institute of Technology Bombay, Powai, Mumbai 400 076, India.
Among the fluorescent dyes, the boron-dipyrromethene (BODIPY) dyes are popular because the
BODIPY dyes have remarkable characteristics such as high absorption coefficients, high fluorescence
yields, long excited state lifetime, good solubility in organic solvents with excellent photo stability 1.
The presence of additional pyrrole ring at the α-position of BODIPY are called α-pyrrolyl BODIPY
which shows better photophysical and electrochemical properties compared to BODIPYs 2. The α-
pyrrolyl dipyrrins can be prepared by demasking BF2 group of α-pyrrolyl BODIPYs. The α-pyrrolyl
dipyrrins containing three pyrrole „‟N”s can act as good ligands to form interesting metal complexes.
Interestingly, the reports on metal complexes of pyrrolyl dipyrrins are very few because of lack of
proper synthetic approaches to obtain pyrrolyl dipyrrin ligands 3. In this poster, we present our
successful synthesis of helical bis Cu(II) complex (I) of open chain hexapyrrolic ligand under simple
reaction conditions (manuscript under preparation). In addition, we also present the synthesis and
properties of a series of BR2 complexes of α-pyrrolyl dipyrrin (II) which were synthesized from BF2
complex of α-pyrrolyl dipyrrin (α -pyrrolyl BODIPY) by treating it with various alkyl- and aryl
magnesium halides under mild Grignard reaction conditions4. Furthermore, we also present out recent
resulst on meso- pyrrolyl BODIPY-Schiff base conjugate (III) as a specific colorimetric optical sensor
for Cu(II) ion (manuscript under preparation).
(I) (II) (III)
R= CH3, C2H5, C4H9 , Phenyl, p-tolyl, p-anisyl.
References:
1. Rao, M. R.; Tiwari, M. D.; Bellare, J.; Ravikanth, M. J. Org. Chem. 2011, 76, 7263.
2. Kaur, T.; Lakshmi, V.; Ravikanth, M. RSC Adv. 2013, 3, 2736.
3. Sharma, R.; Ravikanth, M. Eur. J. Inorg. Chem. 2017, 829.
4. Sabari, P.; Kishor, G. T.; Ravikanth, M. Tetrahedron. 2019, 75, 3371.
164
P72: THE MICRO MACRO PARADOX IN INDUCED FIELD CALCULATIONS AND THE ROLE OF
HR SOLID-STATE NMR
S.Aravamudhan
Department of Chemistry.North Eastern Hill University
A magnetized specimen can be divided into regions referred to as „discrete‟ and „continuum‟ regions
in the context of accounting for the induced field [1] at a specified point. For calculations of
contributions to induced fields it becomes necessary to consider the magnetic moments of
microscopic or semi micro quantities within the specimen which manifest as the macroscopic
magnetization of the material. The magnetic moments can be envisaged to result from a
corresponding charge circulation and consider the magnetic moments as arising from magnetic
susceptibility that is experimentally measured or theoretically calculated. These magnetic moments in
turn induce magnetic fields at any specified point. The procedure for electrical charge polarizations is
applicable in this case of induced magnetic fields and the familiar treatment of local fields is due to
Lorentz. For these calculations becomes necessary to consider a fictitious spherical cavity within the
material around the specified point which is considered as a discrete region. With all the careful
considerations there seems to be an average field within a cavity (where the material has been
removed) and to simplify the matter the cubic symmetry is invoked to assume the induced field zero
within the carved out spherical region. These considerations give rise to an apparent possibility of
including twice some way the carved out spherical region around the site and making amends at the
end of the calculations, when the field is non-uniform [2]. This complication has led to publications
[3,4] which try to explain this paradox. A clarification from the HR PMR results on a single crystal
specimen provides much more clarity on this apparent paradoxical situation pointed out earlier.
References:
1. Magnetized Materials: Contributions inside Lorentz Ellipsoids. S. Aravamudhan, Indian
Journal of Physics,. 2005, Volume 79 (9), 985.
2. http://nehuacin.tripod.com/id3.html (4th Alpine Conference on SSNMR,2004)
3. Local Field Effects and Effective-medium Theory, D.E. Aspnes, American Journal of Physics,
1982, 50(8), 704.
4. Local Fields in Solids: microscopic aspects of dielectrics, S.E Schnatterly and C. Torio,
Reviews of Modern Physics, 1992, 64, 619.
165
P73: Polyampholyte as a modulator of amyloid aggregation and lithium ion carrier
Lakshmi Priya Datta, Sourav Samanta and Thimmaiah Govindaraju*
Bioorganic Chemistry Laboratory,New Chemistry Unit, Jawaharlal Nehru Centre for Advanced
Scientific Research, Jakkur P. O., Bengaluru-560064, Karnataka, India.
Misfolding and aggregation of peptides and proteins is one of the pathological hallmarks of
Alzheimer‟s disease (AD). The etiopathogenesis of AD involve the accumulation of insoluble amyloid-
β (Aβ) plaques in the brain, which disrupt the neuronal network and communication, cause neuronal
death and severe cognitive impairment. Modulation of Aβ aggregation by exogenous therapeutically
active substances is considered as effective strategy to contain the AD progression. Zwitterionic
polymers and polyampholytes are considered as artificial protein mimic systems which are capable of
inhibiting the protein aggregation. In our macromolecule-based aggregation-inhibition strategy,
tryptophan-methacrylic acid (PTMA) based polyampholyte (block co-polymer with cationic and anionic
segments) is synthesized through reversible addition fragmentation chain transfer (RAFT)
polymerization technique. PTMA is found to effectively modulate the Aβ aggregation and rescue
neuronal cells (SHSY5Y cells) from Aβ-induced neurotoxicity as compared to the cationic and anionic
individual homopolymeric segments. Lithium has been reported to exhibit therapeutic role in chronic
neurological diseases including AD. PTMA sequester lithium ion and release in response to stimuli
and can be used as a carrier of lithium for the targeted delivery. These studies have demonstrated
that the dual action PTMA has the potential to be developed into therapeutic candidate for AD.
References:
1. Rajasekhar, K., Chakrabarti, M., Govindaraju, T. Chem. Commun., 2015, 51, 13434.
2. Prince, M., Bryce, R., Albanese, E., Wimo, A., Ribeiro, W., Ferri, C. P. Alzheimer's Dement.
2013, 9, 63.
3. Rajasekhar, K., and Govindaraju, T. RSC Adv. 2018, 8, 23780.
4. Sun, H., Liu, J., Li, S., Zhou, Li., J. Wang, L. Liu, F. Lv, Q. Gu, B. Hu, Y. Ma, Wang,
S. Angew. Chem. Int. Ed. 2019, 58, 5988.
5. Samanta, S., Rajasekhar, K., Govindaraju, T. ACS Chem. Neurosci. 2019, 10, 3611.
6. Samanta, S., Govindaraju, T. ACS Chem. Neurosci. 2019, 10, 4847.
166
P74: Detection Of Host-Guest Supramolecular Inclusion Complexation of Oxime
Functionalized Ionic Liquids and Cyclodextrins
Subhashree Jayesh Pandya, Kallol K Ghosh*
School of Study in Chemistry, Pt. Ravishankar Shukla University, Raipur 492010 (C.G.)
Host-guest complexation between oxime functionalized ionic liquids (ILs) (S)-2-
((hydroxyimino)methyl)-1-(2-((1-(octylamino)-1-oxo-3-phenylpropan-2-yl)amino)-2-oxoethyl)pyridin-1-
ium bromide (2-PyPheC8), (S)-3-((hydroxyimino)methyl)-1-(2-((1-(octylamino)-1-oxo-3-phenylpropan-
2-yl)amino)-2-oxoethyl)pyridin-1-ium bromide (3-PyPheC8) and (S)-4-((hydroxyimino)methyl)-1-(2-((1-
(octylamino)-1-oxo-3-phenylpropan-2-yl)amino)-2-oxoethyl)pyridin-1-ium bromide (4-PyPheC8) and
cyclodextrins (α and β CDs) has been studied. The formation of inclusion complexes (ICs) were
confirmed by UV–Vis and FT-IR which revealed formation of 1:1 stoichiometry. The binding constant
of ICs complex was determined by Job's plot method. Thermodynamic parameters like enthalpy (ΔH),
entropy (ΔS) and Gibb‟s free energy (ΔG) were also calculated. The results have also been validated
by 1H NMR, COSY and NOESY methods. The H-bonding, electrostatic force and hydrophobic
interactions involved in the formation of complexations. The application related to the antidepressant
drugs and inclusion complexes have also been studied.
References:
1. Banjare, M. K.; Behera, K.; Satnami, M. L.; Pandey S.; Ghosh, K. K.; Chem. Phys. Lett.
2017, 689, 30.
2. Gao, Y.; Zhao, X.; Dong, B.; Zheng, L.; Li N.; Zhang, S. J. Phys. Chem. B 2006, 110,
8576.
3. Yu, G.; Hua B.; Han C. Org. Lett. 2014, 16, 2486.
167
P75: Charge transfer dynamics and stability enhancement in inorganic halide Perovskite solar
cells
Samita Mishra, Arijit K. De*, Debrina Jana*
Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali Sector
81, Mohali, Punjab 140306, India.
Hybrid perovskite solar cell technology has attracted incredible interest owing to its both high
conversion efficiency and low processing cost. This emerging technology achieved lab-scale device
efficiency more than 22% by improving the quality of interfaces, carrier transport layers and perovskite
films and substantial steps are being made towards commercialization. Increasing the stability of the
perovskite to make it suitable for long time usage in ambient atmosphere along with understanding
the charge transport property in the device is the most relevant challenging step to be undertaken.
α-CsPbI3 perovskite, the black cubic phase has already been established as a good photovoltaic
active material. This is not stable at room temperature and even if it is prepared and get stabilized at
high temperature, it readily degrades to non-perovskite yellow colour orthorhombic phase. Herein, we
will describe the synthetic protocol of α-CsPbI3 perovskite nanocrystals inside a mesoporous alumina
thin film. The active phase of CsPbI3 remains intact after taking the film at room temperature and
ambient condition and the stability persists for a month. PVP used in CsPbI3 precursor solution
preparation helps to synthesize and stabilize the cubic phase at room temperature by lowering the
surface tension. After formation of CsPbI3, electron and hole transport layers were used to separate
the charges to avoid charge recombination and femtosecond broadband transient absorption
spectroscopy was utilized to investigate the charge transfer kinetics of as synthesized mesostructured
perovskite. The spectral data confirms the efficient charge transfer occurs from CsPbI3 to charge
conducting layers.
References:
1. Li, B.; Zhang, Y.; Fu, L.; Yu, T.; Zhou, S.; Zhang, L. and Yin L. Nat. Commun. 2018, 9, 1076.
2. Lee, M. M.; Teuscher, J.; Takurou, T. M.; Murakami, N. and Snaith, H. J. Science 2012, 338,
643.
3. Takhellambam, D.; Meena, T. R. and Jana, D., Chem. Commun. 2019, 55, 4785.
4. Mondal, N. and Samanta A. Nanoscale 2017, 9, 1878.
5. Manser, J. S. and Kamat,, P. V. Nature Photonics 2014, 8, 737.
168
P76: Unravelling the role of water in ultrafast excitation energy transfer within nano-
architectures of chlorophyll a
Yogita Silori, Sakshi Chawla and Arijit K. De*
Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali,
Knowledge City, Sector 81, SAS Nagar, Punjab 140 306, India.
The mechanism of excitation energy transfer (EET) in natural light harvesting systems which includes
absorption of light energy by antenna chromophores followed by the exchange of energy among
various chromophores with near-unit efficiency and finally funneling of energy towards the reaction
center where it is trapped leading to a charge separation, has attracted high interest [1,2]
. The
architectural principle of chromophore-protein complexes is too complicated to be replicated in
artificial light-harvesting devices. However, numerous interesting works are done in designing
supramolecular architectures that mimic the organization of various chromophores within the
photosynthetic antenna complex of green sulfur bacteria, called chlorosome [3]
. Chlorophyll a is the
highest utilized photosynthetic pigment due to its efficient absorption of red light and its redox
properties. Interaction between chlorophyll molecules (and also with its local environment) gives rise
to formation of various architectures like polymer (cylindrical reverse micelle), aggregates (T-shaped
oligomers which form micelles), etc. by varying the ratio of acetonitrile (ACN) and water [4]
. We studied
ultrafast excited state dynamics of these architectures using femtosecond pump-probe spectroscopy
to unravel the structure-function relationship mediated via water molecules. All the architectures show
a broad excited state absorption (ESA) band in the region of 490-650 nm which show no significant
change in spectral traces with increasing probe delay, in ACN. However, in the other two cases
(mixtures of ACN/water), the ESA band shows a blue shift as well as spectral narrowing with the
pump-probe delay; this clearly indicates presence of vibrational cooling which takes place due to
faster thermal diffusivity in presence of water. Quite interestingly, the vibrational cooling is followed by
stimulated emission with almost no red shifts in spectra, suggestive the absence of significant polar
solvation dynamics.
References:
1. R.E. Blankenship, Molecular Mechanisms of photosynthesis, Blackwell Science Ltd., USA,
2002.
2. R. E. Blankenship and K. Matsuura, in Advances in Photosynthesis and Respiration, ed.
B. R. Green and W. W. Parson, Springer, Arizona, 2003, vol. 13, ch.6, pp. 195-217.
3. T. S. Balaban, Acc. Chem. Res., 2005, 38, 612–623.
4. A. Agostiano, P. Cosma, M. Trotta, L. Monsù-Scolaro and N. Micali. J. Phys. Chem. B,
2002, 106, 1282012829.
169
P77: Color Tuning of Mixed Lanthanide Triggered by pH
Manaranjan Sahu, Ajay Kumar, and Uday Maitra*
Department of Organic Chemistry, Indian Institute of Science, Bangalore, 560012
In this poster, we will present the pH-dependent sensitization of Tb(III) using methyl salicylate (MS).
Methyl salicylate was found to be a specific sensitizer for Tb(III) but not for Eu(III). Subsequently,
doping of Eu(III) in a mixture of Tb(III) and MS resulted in color change from green to orange
depending upon the pH of the solutions. Photophysical studies confirmed energy transfer from Tb(III)
to Eu(III) in the lanthanide mixed Tb(III)/Eu(III)-MS system.
References:
1. Bhowmik; S.; Maitra, U. Chem. Commun. 2012, 48, 4624-4626.
2. Banerjee, S.; Kandanelli, R.; Bhowmik, S.; Maitra, Soft Matter 2011, 7, 8207-8215.
3. Brittain, H. G. Inorg. Chem. 1979, 18, 1740-1745.
pH 6 pH 7 pH 8 pH 9
UV light
Day light
Tb(III)/Eu(III)
9:1
170
P78: CATALYST FREE SYNTHESIS OF 3,1-BENZOXATHIIN-4-ONES/1,3-BENZODIOXIN-4-ONES
M. Malarvizhi and S. Muthusamy*
School of Chemistry, Bharathidasan University,Tiruchirappalli-620024, Tamilnadu
Heterocycles form the largest of classical divisions of organic chemistry and are of immense
importance biologically and industrially. One striking structural feature inherent to heterocycles,1 which
continues to be exploited to great advantage by the drug industry, lies in their ability to manifest
substituents around a core scaffold in defined three dimensional representations. Between them,
sulfur and oxygen containing heterocyclic compounds have maintained the interest of researchers
through decades of historical development of organic synthesis.2 Resulting from the derivation of
homocyclic hydrocarbons from the substitution of the ring carbon atom by sulfur heteroatom, their
relevance comes from the significant changes in cyclic molecular structure engraved by differences in
electronic configuration, unshared pair of electrons and ultimately the electronegativity between
heteroatoms and carbon.3
From the literature, we observed that 3,1-benzoxathiin-4-ones4 / 1,3-
benzodioxin-4-ones were commonly synthesized by the inter- and intramolecular metal catalyzed
cyclizations of alkynes and thiosalicylic acids / salicylic acids. To the best of our knowledge, there is
no report available for the synthesis of these systems using propargyl alcohols. We herein
demonstrate the reaction of thiosalicylic acid / salicylic acid and propargylic alcohols 1 for the
synthesis of 3,1-benzoxathiin-4-ones / 1,3-benzodioxin-4-ones 2 and 3 without using any catalyst.
The details of this reaction will be discussed.
Scheme: Synthesis of 3,1-benzoxathiin-4-ones 2 / 1,3-benzodioxin-4-ones 3
References:
1. Dua, R.; Shrivastava, S.; Sonwane, S. K.; Srivastava, S.K. Advan. Biol. Res. 2011, 5, 120.
2. Valverde, M. G.; Torroba, T. Molecules 2005, 10, 318.
3. Marcos, C. F.; Polo, C.; Rakitin, O. A.; Rees, C. W.; Torroba, T. Angew. Chem. Int. Ed. Engl.
1997, 36, 281.
4. (a) Sonehara, T.; Murakami, S.; Yamazaki, S.; Kawatsura, M. Org. Lett. 2017, 19, 4299; (b)
Nishina, Y.; Miyata, J. Synthesis 2012, 44, 2607.
171
P79: Facile Synthesis of Fused Sipro Pyrrolidine-oxindole Derivatives via 1,3-Dipolar
Cycloaddition of Isatins, α-Amino acids and Heterobicyclic Alkenes
Subramani Kumaran and Kanniyappan Parthasarathy*
Department of Organic Chemistry, University of Madras, Chennai (600025), India
1,3-Dipolar cycloaddition reaction have emerged as highly useful methods for assembling of complex
heterocyclic molecules from simple starting materials.1 Particularly, azomethine ylide is a favourable
key intermediate to build pyrrolidines, sipro pyrrolidines, 3-spiropyrrolidine oxindoles and
pyrrolizidines in a single step with multiple stereocenters.2 Spiropyrrolidine oxindole skeletons are
found in a wide range of naturally occurring compounds that shows various unique biological
activities.3 We developed a facile synthesis of various fused spiro-pyrrolidine-oxindoles from isatins,
amino acids with heterobicyclic alkenes via 1,3-dipolar cycloaddition. For the first time, we used
heterobicyclic alkenes as a dipolarophile in 1,3-dipolar cycloaddition of the azomethine ylide
generated via decarboxylation. Triflic acid mediated aromatization of cycloaddition products has been
demonstrated. A possible mechanism is proposed that the formation of iminium carboxlate
intermediate (I), azomethine ylide intermediate (II) via decarboxylation,4 subsequent 1,3-dipolar
cycloaddition with oxabenzonorbornadiene to give cycloaddition product.
References:
1. (a) Kanemasa, S. Synlett, 2002, 1371. (b) Gothelf, K. V.; Jorgensen, K. A. Chem. Rev. 1998,
98, 863.
2. (a) Najera, C.; Sansano, J. M. Angew. Chem. Int. Ed. 2005, 44, 6272. (b) Wang, Y.-M.;
Zhang, H.-H.; Li, C.; Fan, T.; Shi, F. Chem. Commun. 2016, 52, 1804.
3. Jiang, T.; Kuhen, K. L.; Wolff, K.; Yin, H.; Bieza, K.; Caldwell, J.; Bursulaya, B.; Wu, T. Y.; He,
Y. Bioorg. Med. Chem. Lett. 2006, 16, 2105.
4. Bharitkar, Y. P.; Das, M.; Kumari, N.; Kumari, M. P.; Hazra, A.; Bhayye, S. S.; Natarajan,
R.; Shah, S.; Chatterjee, S.; Mondal, N. B. Org. Lett. 2015, 17, 4440.
172
P80: Nickel-Catalyzed Synthesis of Substituted Indolo[2,1-a]isoquinolines via Cyclization of 2-
(2-bromophenyl)-1H-indoles with Alkynes
Sampath Thavaselvan and Kanniyappan Parthasarathy*
Department of Organic Chemistry, University of madras, Chennai-25 (India)
The nitrogen containing heterocycle such as indole occupies a remarkable role in wide variety of
natural products, drug molecules1 and high performance electronic devices.
2 Transition-metal
catalyzed constructions of various polyaromatic hydrogens (PAHs) by using aryl halides with alkynes
have been developed through C-H bond activation.3,4
So far, to the best of our knowledge the
formation of C-C and C-N bond formation by using Ni-catalyzed cyclization were less explored in
literature. However, the transition metals such as Rh, Pd- catalyzed annulations were well known.
Based on the literature survey, we developed a reaction of 2-(2-bromophenyl)-1H-indoles with internal
alkynes in the presence of Ni(II)-catalyst/PPh3/Zn to afford the annulated products with good yield.
The mechanism believed to proceed an oxidative addition of aryl halides with Ni(0), coordinative
insertion of alkynes to give nickel intermediate (I) followed by reductive elimination sequence.
References:
1. (a) Gribble, G. W. In Comprehensive Heterocyclic Chemistry II; Katrizsky, A. R., Rees, C. W.,
Scriven, E. S. V., Eds.; Pergamon Press: New York, 1996, 2, 207. (b) Le Quesne, P. W.;
Dong, Y.; Blythe, T. A. Alkaloids: Chem. Biol. Perspect. 1999, 13, 237.
2. (a) Wang, C.; Dong, H.; Hu, W.; Liu, Y.; Zhu, D. Chem. Rev. 2012, 112, 2208. (b) Dong, H.;
Fu, X.; Liu, J.; Wang, Z.; Hu, W. Adv. Mater. 2013, 25, 6158.
3. (a) Shi, Z.; Ding, S.; Cui, Y.; Jiao, N. Angew. Chem., Int. Ed. 2009, 48, 7895. (b) Morimoto,
K.; Hirano, K.; Satoh, T.; Miura, M. Org. Lett, 2010, 12, 2068.
4. Wan, D.; Li, X.; Jiang, R.; Feng, B.; Lan, J.; Wang, R.; You, J.; Org. Lett, 2016, 18, 2876.
173
P81: Design and Development of sustainable poly (benzoxazine-co-maleimide) materials for
autonomous self-healing applications
S.Sriharshitha,S.Devaraju* and K.Krishnadevi*
Division of Chemistry, Department of Science and Humanities Vignan’s Foundation for Science,
Technology and Research (VFSTR), Guntur, India
In this work, an attempt has been made to develop bio-based eco-friendlypoly(benzoxazine-co-
maleimide) [EPBz-MA] materialforautonomous self-healing applicationsusing eugenol based
benzoxazine (EBz-AEE) and maleic anhydride (MA). EBz-AEE is synthesized using eugenol,
aminoethoxyethanol (AEE) and paraformaldehyde through Mannich reaction. Later, EBz-AEE is
copolymerized with anhydride precursor(maleic anhydride). The structure of the EBz-AEE is
confirmed using Fourier transform infrared (FT-IR) and Nuclear Magnetic Resonance (NMR)
spectroscopy. The thermal properties of theEPBz-MA arecheckedusing differential scanning
calorimetry (DSC) and thermo gravimetric analysis (TGA) analysis. Further,the self-healing behavior
of the bio-based EPBz-MAis checked with applyingmild external pressure. The developed EPBz-MA
shows good and repeated self-healing abilitydue to supra-molecular action and inter and intra
hydrogen bonding interactions between carboxylic acid and phenolic hydroxyl groups in the network
structure.Thus, the developed cost effective and environment friendly self-healing EPBz-MAmatrices
will be useful for further expanding the uses of benzoxazines in various high performance applications
including coating, automobile, printed circuit board, and etc. with longer self-life.
References:
1. Fu, F., Huang, M., Zhang, W. et al. 2018 SciRep 8, 10325
2. Liang, J.-Y.; Shin, S.-R.; Lee, S.-H.; Lee, D.-S Polymers 2019, 11, 1674.
3. Cheng, C., Zhang, X., Chen, X. et al.2016J Polym Res 23, 110
AEE
Eugenol
O N
H3CO
CH2
OOH
+
OOO
⁺Ebz-AEE
Maleic anhydride
Δ 60 c to 180 c
(20 c/hr)
EPBz
EPBz Damaged EPBz Healed EPBz
174
P82: A Tethered Oxycarbenium Ion Initiated Epoxide Opening Reaction: Sharpless Epoxides to
Fully Protected Triols
Meera Johny, Rosemary Philip, Rajendar Goreti*
School of Chemistry, IISER Thiruvananthapuram
A new methodology was proposed based on tethered oxy-carbenium ion initiated epoxide opening to
synthesise fully protected triols from 2,3-epoxy alcohols. The conversion happens in two steps using
an appended alkoxide as a nucleophile, which is obtained from an acetal-protecting group to yield 5
or 6 membered cyclic acetals as products. The control of regiochemistry of epoxide opening reaction
to produce either C3 alkoxylated products or C2 alkoxylated products, fairly depends upon electronic
and steric effects of substrate. Also, the epoxide opening found to be highly stereoselective a
complete inversion at stereogenic center is observed.
Scheme: Lewis Acid Catalyzed Cyclization of Epoxy Aceta
References:
1. Sharpless, K. Barry, et al. Pure and Applied Chemistry. 1983, 55, 589-604.
2. Hanson, Robert M. Chemical Reviews 1991, 91. 437-475.
3. Vol‟eva, V. B., et al. Russian Journal of Organic Chemistry, 51, 7 ,2015, 915-917.
175
P83: Modulation of Nitric Oxide (NO) Release by Cuprous Oxide (Cu2O) Polymorphs: Crystal-
Facet-Dependent Denitrosylation of S-Nitrosothiols
Sourav Ghosh, Punarbasu Roy, Sanjay Prasad and Govindasamy Mugesh*
Inorganic and Physical Chemistry Department, Indian Institute of Science, Bangalore
Nitric oxide (NO), a gaseous molecule is involved in a variety of important biological processes such
as signalling molecule in the nervous system, vasodilator in the cardiovascular system, and it is used
as a key molecule by the immune system to fight against infections.1 As NO is synthesized in
endothelial cells by eNOS, the low level of NO due to impairment of the enzyme activity affects the
endothelial function and signal transduction. On the other hand, elevated levels of NO cause
nitrosative stress related signalling, leading to post-translational modification of many proteins,
neurotoxicity and apoptosis.1c-e
Therefore, the imbalance between the nitrosylation and denitrosylation
activities of enzymes affect the NO concentration and show beneficial or deleterious biological effects.
Synthetic compounds such as organic nitrates (RONO2) and nitrites (RONO), metal nitrosyl
complexes, N-nitrosamines (RN(NO)R′), S-nitrosothiols (RSNO) have been used to generate NO for
biological applications.2a
However, the controlled release of NO from the nitrosylated compounds at
physiological pH remains a challenge. In this poster, we demonstrate that Cu2O-based nanomaterials
can release NO from S-nitrosothiols and provide the first experimental evidence that the
denitrosylation activity Cu2O nanocrystals can be altered by changing the crystal facets within the
same crystal system.2b
The detailed mechanistic investigation revealed that the {111} crystal facet in
Oh is more efficient than the {011} and {001} facets present in RDh and cube, respectively, in the
denitrosylation of RSNO (Fig. 1).2b
Further, {111} facets may be employed for a quick release of NO,
whereas the {011} facets will be useful for a slow and sustained release of NO. Therefore, the facet-
dependent denitrosylation activity may find potential applications in modulating the NO bioavailability
under disease conditions such as endothelial dyfunction in which the physiological NO signaling is
severely impaired.
References:
1. Moncada, S.; Palmer, R. M.; Higgs, E. A. Pharmacol. Rev. 1991, 43, 109-142; b) The Nobel
Prize in Physiology or Medicine 1998. Nobelprize.org; c) Melino, G.; Bernassola, F.; Knight,
R. A.; Corasaniti, M. T.; Nistic, G.; Finazzi-Agro, A. Nature 1997, 388, 432-433;
2. Wang, P. G.; Xian, M.; Tang, X.; Wu; X.; Wen, Z.; Cai, T.; Jaczuk, J. A. Chem. Rev. 2002,
102, 1091-1134; b) Ghosh, S.; Roy, P.; Prasad, S.; Mugesh, G. Chem. Sci. 2019, 10, 5308-
5318.
Figure 1. Denitroisylation of RSNO and detection of nitric oxide.
176
P84: Nanoceria-Based Cell Membrane Disruptive Phospholipase-Mimetic Nanozymes
Kritika Khulbe, Govindasamy Mugesh*
Inorganic and Physical Chemistry Department, Indian Institute of Science, Bangalore
Antimicrobial resistance (AMR) has abrogated the initial phase of chemotherapeutic effects of
antimicrobial drugs propounded by the Nobel Prize winning discovery of penicillin by Sir Alexander
Fleming, Ernst Boris Chain and Sir Howard Walter Florey.[1a]
Surprisingly, gram-positive bacteria have
in-built cell death mechanism using ribosomally-synthesized bactericidal peptides, “lantipeptides”
which are responsible for disruption of the cell membrane integrity by formation of pores on the
surface or inhibition of cell wall synthesis ultimately leading to apoptosis. However, analogous
antibiotic effect in gram-negative bacteria is not known due to the inability of lantipeptides to cross the
outer cell membrane barrier.[1b-c]
Thus, a material capable of traversing the outer membrane of gram-
negative bacteria would have potential antibacterial activity on a wide range of bacteria.Among the
new approaches, the redox active catalytic activity of CeO2 has gained attention.[2a]
In this study, we
used a nanomaterial functionalization-based strategy using coated cerium oxide-based nanoparticles
for the targeting and disruption of bacterial cell membrane. We describe for the first time the cell
membrane degradation ability of a remarkable phospholipase-like active ceria nanozyme (Figure 1).
The dual oxidation state (Ce3+
and Ce4+
) surface provide catalytic site for binding and hydrolysis of
long-chain phospholipids present on the bacterial cell membrane, whereas the polymer coating
provided sufficient dispersibility to the nanostructure for enhanced antibacterial activity. The
phospholipase activity of our coated nanozyme has enhanced bactericidal effect on a broad range of
planktonic and biofilm bacteria.[2b]
Broad-spectrum phospholipase mimetic of the nanozyme has
potential application for preventing bacterial colonization and biofilm formation on the surface of
urinary catheters, a major cause of the health care-associated urinary tract infections
Figure1:
References:
1. a) Alekshun, M. N.; Levy, S. B. Molecular Mechanisms of Antibacterial Multidrug Resistance.
Cell 2007, 128, 1037-1050; b) Knerr, P. J.; van der Donk, W. A. Discovery, Biosynthesis, and
Engineering of Lantipeptides. Annu. Rev. Biochem. 2012, 81, 479–505; c) Li, Q.; Lopez, M.
M.; Kuipers, O. P. Increasing the Antimicrobial Activity of Nisin-Based Lantibiotics against
Gram-Negative Pathogens. Appl. Environ. Microbiol. 2018, 84, e00052-18.
2. a) Xu, C.; Qu, X. G.; Cerium Oxide Nanoparticle: A Remarkably Versatile Rare Earth
Nanomaterial for Biological Applications. NPG Asia Mater. 2014, 6, e90; b) Manuscript
submitted.
177
P85: One-pot synthesis of novel Ru(II)-p-cymene-2-aryl benzimidazole (BIZ), benzothiazole
(BTZ) and benzoxazole (BOZ) scaffolds: the influence of regioisomer on cytotoxicity and
reactivity towards DNA and protein
Ashaparna Mondala, Utsav Sen
b, Nilmadhab Roy
a, Priyankar Paira*
a, Bipasha Bose
b
aDepartment of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore-
632014, Tamil Nadu, India bStem cells and Regenerative Medicine Centre, Yenepoya University, Mangalore, Karnataka, India
During last few decades researchers came up with a lot of advancement in diagnosis and treatment of
cancer. Herein, a one-pot protocol was adopted to synthesize Ru(II)-arene 2-aryl benzimidazole/
benzothiazole/ benzoxazole complexes under continuous sonication. A series of Ruthenium arene
complexes are reported for anticancer screening in terms of cytotoxicity and selectivity against cancer
cell lines. The regioisomers of these complexes are also isolated by preparative thin layer
chromatography and their stability was well supported by DFT calculation. [(η6-p-cymene)Ru-2-(5, 6-
dichloro-1H-benzo[d]imidazole-2-yl)quinoline] (11j) was found to be significantly potent and selective
in Caco-2, Hela cell line respectively compared to cisplatin. These types of Ru(II)-arene complexes
exhibited effective intercalation binding with DNA. Since, [(η6-p-cymene)Ru-2-(6-nitro-1H-
benzo[d]imidazole-2-yl)quinoline] (11f´) was identified as good fluorescent as well as potent scaffold
it can be a developed as good drug candidate for cancer theranostics. Complex 11j was further tested
against more invasive cancer cell line- Ht-29 (colon cancer cell line) to understand the mechanism of
cancer cell apoptosis.
References:
1. C. G. Hartinger, S. Zorbas-Seifried, M. A. Jakupec, B. Kynast, H. Zorbas and B. K. Keppler, J.
Inorg. Biochem., 2006, 100, 891.
2. N. P. Barry and P. J. Sadler, Chem. Commun., 2013, 49, 5106.
3. S. B. Lara, L. Salassa, A. Habtemariam, O. Novakova, A. M. Pizarro, G. J. Clarkson, B.
Liskova, V. Brabec and P. J. Sadler, Organometallics, 2012, 31, 3466.
4. S. K. Subran, S. Banerjee, A. Mondal and P. Paira, New J. Chem., 2016, 40, 10333.
Figure: Design of Ru(II)-η6-p-cymene benzimidazole (BIZ), benzothiazole (BTZ) and benzoxazole
(BOZ) scaffolds and cell apoptosis mechanism.
178
P86: Utility of 2-Amino pyridine: A hit to lead identification study
Nishanth.R, Kaushik Chanda*
Department of Chemistry, Vellore Institute of Technology, Vellore-632014, India.
2-aminopyridine is a classic example of key core structure, used to graft with other complex groups in
achieving potent pharmacophores with broad spectrum biological importance. It contributes to
valuable part of marketed drugs such as Piroxicam (Anti-inflammatory), Sulfapyridine (Antibacterial)
Tripelennamine (Anti histaminic), Delavirdine (Anti-HIV) etc. Research in pharmaceutical industry is
nowadays eyeing on discovery of small heterocycles as these form less number of metabolites invivo
and also eradicate the chances of toxicity due to multiple bulkier groups2.In this context we developed
an expeditious catalyst-free heteroannulation reaction in green solvent under microwave irradiation
starting from 2-aminopyridine to access imidazo[1,2-a]pyridines/ pyrimidines/ pyrazines and evaluated
their antimicrobial and anti-inflammatory activity3. Screening results uncovered three derivatives with
strong inhibition of albumin denaturation and two derivatives were active on Proteus and Klebsiella
bacteria. To further evaluate utility of 2-aminopyridine we developed a synthetic strategy to
accomplish thizolidine-2-imines by reacting 2- aminopyridines/pyrimidines and pyrazines with
substituted isothiocyanates
References:
1. Bolliger, J.L.; Oberholzer, M.; Frech,C.M. Advanced Synthesis & Catalysis. 2011, 353, 945.
2. Nakamura, I.; Yamamoto, Y. Chem. Rev., 2004, 104, 2127.
3. Nishanth, R.; Balamurali,M.M.; Maiti,B.; Thakuria,M.; Chanda, K. ACS Comb. Sci. 2018,
20,164.
179
P87: Computational Studies of Selective N-methylation of Nicotinamide as an Epigenetic
Mechanism in Cancer
Masthan Thamim, Krishnan Thirumoorthy*
Department of Chemistry, School of Advanced Science, Vellore Institute of Technology, Vellore-
632014, Tamil Nadu, India
The selective N-methylation reaction of nicotinamide by Nicotinamide N-methyltransferase (NNMT) in
the biological nanospace is being considered as one of the most common epigenetic changes in
biology1. The methylation in biology is the fundamental biotransformation reaction which alters the
structure and function of the biomolecules. The changes in methylation potential in biochemical
reaction lead to hyper- and hypomethylation thus it triggers the cancer cell signaling2. The NNMT
catalyzes the N-methylation of nicotinamide using S-adenosyl-L-methionine to produce 1-
Methylnicotinamide (1-MNA) instead of 7-Methylnicotinamide (7-MNA) remains unexplored though
inspiring 7-MNA similar kinds reported with Glycine N-methyltransferase in prostate cancer3. In this
direction, the present work aims to address mechanistic aspects of selective N-methylation of NA in
the active site of NNMT using computational quantum chemical calculations. As a result, the
formation of 1-MNA shows thermodynamic and kinetic stabilities as compared to 7-MNA. The 1-MNA
formation alters the methylation genomic pattern which triggers the activation of oncogenic signaling
pathway.
References:
1. Aksoy, S.; Szumlanski, C. L.; Weinshilboum, R. M. Human Liver Nicotinamide N-
Methyltransferase. CDNA Cloning, Expression, and Biochemical Characterization. J. Biol.
Chem. 1994, 269 (20), 14835–14840.
2. Ulanovskaya, O. A.; Zuhl, A. M.; Cravatt, B. F. NNMT Promotes Epigenetic Remodeling in
Cancer by Creating a Metabolic Methylation Sink. Nat Chem Biol. 2013, 9.
https://doi.org/10.1038/nchembio.1204.
3. Sreekumar, A.; Poisson, L. M.; Rajendiran, T. M.; Khan, A. P.; Cao, Q.; Yu, J.; Laxman, B.;
Mehra, R.; Lonigro, R. J.; Li, Y.; et al. Metabolomic Profiles Delineate Potential Role for
Sarcosine in Prostate Cancer Progression. Nature 2009. https://doi.org/10.1038/nature07762.
180
P88: Development of New Coumarin Hydrozone as Fluorogenic Chemosensor for Lu3+
ion
Determination
Mujthaba Aatif A, S.K. Ashok Kumar*
Department of Chemistry,School of Advanced Sciences, Vellore Institute of Technology, Vellore-
632014. Tamil Nadu, India.
A new coumarin hydrozone Ligand (L) has been synthesized for the selective determination of Lu3+
by
spectrofluorometric technique. The ligand L exhibits an emission band at 490 nm upon excitation at
437nm. The ligand L, upon interaction with Lu3+
the emission band increased with a five-fold
enhancement at 490 nm in DMSO: water (7:3, v/v) media. The formation of host-guest complexation
between L and Lu3+
found to be 2:1 confirmed by Job's and the binding constant (Ka = 1.43 ×104 M
-2)
was estimated by the Benesi-Hildebrand method. The ligand L could work in the pH range from 2.0 to
5.0 without interfering form other interfering ions. The limit of detection of L was found to be 70 nM.
Further, the binding mechanism of L with Lu3+
was supported by 1H-NMR, FT-IR and ESI mass
spectral studies and experimental results were well supported with theoretical studies.
References:
1. R. Selva Kumar, S.K. Ashok Kumar, Kari Vijayakrishna, Akell Sivaramakrishna, C.V.S.
Brahmnanda Rao, Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy
214 (2019) 32.
2. Lina Wang, Juanjuan Tang, Ning Sui, Xing Yang, Luyao Zhang, Xiaojun Yao, Qinfei Zhou,
Hailian Xiao, Shaoping Kuang and William W. Yu, Anal. Methods, 2017, 9, 6254.
3. F. Faridbod, M. Sedaghat, M. Hosseini, M.R. Ganjali, M. Khoobi, A. Shafiee, P. Norouzi,
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 137 (2015) 1231.
4. Morteza Hosseini, Mohammad Reza Ganjali, Zahra Rafiei-Sarmazdeh, Farnoush Faridbod,
Hassan Goldooz, Alireza Badiei, Parviz Nourozi, Ghodsi Mohammadi Ziarani, Analytica
Chimica Acta 771 (2013) 95.
181
P89: Development of Fluorescein Based Ruthenium (II) Complex for Cytotoxicity and
Antibacterial Applications
S. Pravinkumara,b
, S. K. Ashok Kumara*
, I. Pradeepb*
aDepartment of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore-
632014 bDepartment of chemistry, Bishop Heber College (Autonomous), Tiruchirappalli-620017.
A new fluorescein-based ruthenium (II) complex was synthesized and characterized by various
spectroscopic techniques. The light absorbing and emission property of Ru(II) complex were studied
by using spectrophotometry and spectrofluorimetric methods. The results reveal that the complex
shows two major absorption peaks were appeared 300 nm and 420 nm which is due to the π-π*
transitions and metal to ligand charge transfer (MLCT) respectively. Its shows the emission peak
appeared at 530 nm upon the excitation at 420 nm. Further, biological studies such as cytotoxicity
and antibacterial activity were performed and results reveals that Ru(II) complex exhibits higher
activity against Proteus vulgaris bacteria. Further, it shows a potency and cytoselectivity in lung
cancer cell line [A549] with the IC50 concentration of 9.74 µM. Hence, this Ru(II) complex was found to
be useful for cytotoxicity and antibacterial agent.
References:
1. I.Pradeep, B.Balajothi, S.Arunachalam, R.Dhivya, A. Vinothkanna, M.Abdulkadher Akbarshab
and S. Sekar RSC Adv., 2016, 6, 318
2. C.F. Ramogida and C. Orvig, “Chem. Commun. (Cambridge, U. K.), 2013. 49: p. 4720
3. N.Jadeja, K.M.Vyas, K.K.Upadhyay, R.V.Devkar. RSC Adv., 2017, 7, 17107.
Fluorescein Ruthenium
complex
Antibacterial
Study Cytotoxicity
Study
182
P90: Design and synthesis of visible organic light-emitting materials
Leyana K Shaji, Ashok Kumar S.K*.
Department of Chemistry, School of Advanced Sciences.Vellore Institute of Technology, Vellore -
632014.
In this work, a new Schiff‟s base (S) synthesised and characterised as new class of solid-state
emissive organic fluorophore by reacting 2-amino-benzo-isoquinoline-1,3-dione with para-substituted
aldehyde leads under simple reaction conditions. Results show that on excitation of S at 380 nm in
the solid state, it exhibits a new emissive peak at 585 nm with stokes shift of 205 nm while in the
solution phase very weak emissive power. The high solid state emissive is due perfect π-π stacking in
the system while in solution phase this structure get destroyed which leads to less emission. The
observed photo physical properties were supported by DFT/TDDFT calculations in both solid phase.
All these preliminary results indicated that S can act as quite promising light-emitting materials for
OLED applications.
Figure: Absorbance and emission spectral response of S in solid state.
References:
1. Bera, M. K.; Chakraborty, C.; Malik, S. J. Mater. Chem. C 2017, 5, 6872.
2. Malina, I.; Kampars, V.; Turovska, B.; Belyakov, S. Dye. Pigment. 2017, 139, 820.
3. Dhar, J.; Venkatramaiah, N.; Anitha, A.; Patil, S. J. Mater. Chem. C 2014, 2, 3457.
4. Tagare, J.; Vaidyanathan, S. J. Mater. Chem. C 2018, 6, 10138.
183
P91: Synthesis and Characterisation of Substituted 2-oxo-4H-chromen-3-acrylonitrile
Derivatives for Optoelectronic Applications
Suman Josph, Selva Kumar R, S.K. Ashok Kumar*
Department of Chemistry,School of Advanced Sciences, Vellore Institute of Technology, Vellore -
632014.
In this work, we have design and synthesized new 2-oxo-4H-chromen-3-acrylonitrile derivatives (4a-
4j) using multicomponent one pot synthesis. All synthesised derivatives are characterised by various
spectroscopy and mass analysis. The emission study of 4e, 4i, and 4j in solid state and 4b, 4e, 4g
and 4h in solution phase exhibits high emission characteristics. The solvatochromism study shows
that all compounds are having positive solvatochromism nature. The derivatives 4b, 4g and 4h shows
good AIE and rest of the derivatives follow ACQ properties. The TDG/DSC study shows that the
compound having high thermal stability. Besides, the observed photophysical properties are
correlated with theoretical calculation.
References:
1. R. Sébastien, E. Gwenaëlle, I. Martin, et al., Dyes and Pigments, 2018, 156:116.
2. B. Umamahesh, M. Saravanakumar, D.T. Manojkumar, et al. RSC Adv., 2016, 6, 58549.
3. W. Bentoumi, J. C. Mulatier, P. A. Bouit, et al., Chem. Eur. J., 2014, 20, 8909.
184
P92: One-Pot Multi-component Biginelli Reaction Catalyzed by Ionic Liquid Immobilized
Proline(s) Organocatalyst
Prabhakara M D, Barnali Maiti*
Department of Chemistry, School of Advanced Science, Vellore Institute of Technology,Vellore-
632014, Tamil Nadu, India.
A highly efficient synthetic methodology has been developed for one-pot synthesis of 3,4-
dihydropyrimidin-2-(1H)-ones catalyzed by ionic liquid immobilized proline(s) organocatalyst at room
temperature in IPA solvent. Three components such as aryl aldehydes, β-ketoesters and urea in one-
pot underwent Biginelli reaction using 5 mol% ionic liquid immobilized proline(s) organocatalyst at
room temperature. This method offers several advantages such as low catalyst loading percentage,
short-reaction times, mild reaction conditions, excellent yields, chromatography-free, and metal-free
synthesis. The organocatalyst could be recycled and reused five times without significant loss of
catalytic activity. The final product was characterized by 1H NMR,
13C NMR, Mass and IR spectra
analysis.
Scheme 1: Multi-component Biginelli Reaction catalyzed by ionic liquid-immobilized proline(s)
organocatalyst.
References:
1. Prabhakara, M. D.; Maiti, B. Res. Chem. Inter. 2020, (in press).
185
P93: Ramification of donor-acceptor alternation to analyse emission behaviour of V-shaped
thiophene donor and thiazole acceptor towards aggregation pathway
P. S. Umabharathi and S. Karpagam*
Department of Chemistry, School of Advanced Science, VIT University,Vellore -14. Tamil Nadu, India
A novel series of D-π-A-π-D configured conjugated oligomer with V type structure were efficiently
synthesized by Wittig condensation reaction. Thiophene and thiazole type of donor-acceptor based
series of conjugated oligomer, Oligo-4,4'-benzothiazole-5,6-diylbis (ethane-2,1-diyl)bis (thiophene-5,2-
diyl)bis (N, N-diphenyl aniline) were synthesized. This core moiety exclusively selected to increase
the planarity, rigidity, stability and extend the π–conjugation. D-π-A-π-D configured conjugated
oligomer were analysed from FT-IR, NMR technique and optical properties were done by UV-visible
(optical absorption). The photo luminescence spectrum of the oligomer was observed. By increasing
the water: THF fraction, switching of different emission colour, observed different emission
wavelength and particle was aggregated which was examined from PL spectroscopy.
Scheme: Synthesis of D-π-A-π-D configured conjugated oligomer with V-type structure.
References:
1. Kakekochi, V.; Chandrasekharan, K.; Kumar, U Dyes and Pigments. 2020, 3, 108181.
2. Jagadeesan, S.; Mahesh, K.; Karpagam, S.ChemistrySelect. 2019, 4(37), 11196-205.
186
P94: A Robust and Recyclable Ionic liquid Supported Copper (II) Catalyst for the Synthesis of
5-Substituted-1H-tetrazoles using Microwave Irradiation
R D Padmaja and Kaushik Chanda*
Department of Chemistry,School of Advanced Sciences, Vellore Institute of Technology, Vellore.
A novel and robust ionic liquid supported copper (II) catalyst has been developed and explored for the
efficient synthesis of 5-substituted-1H-tetrazoles using microwave irradiation. The use of ionic liquid
supported catalyst facilitated for the efficient isolation of the tetrazole products by simple extraction
with organic solvent with high purity. Recovered ionic liquid supported copper (II) catalyst could be
recycled for three times for the synthesis of tetrazole products with high purity. This synthetic protocol
offers a very clean, convenient, and microwave assisted environment friendly method for the efficient
synthesis of 5-Substituted-1H-tetrazoles with high yield.
References:
1. Amantini, D.; Beleggia, R.; Fringuelli, F.; Pizzo, F.; Vaccaro, L. J. Org. Chem., 2004, 69,
2896.
2. Jiun-Jie Shie and Jim-Min Fang* ; J. Org. Chem. 2007, 72, 3141
3. Maiti, B.; Chanda, K. RSC Adv., 2016, 6, 50384.
4. Padmaja, RD.; Rej, S.; Chanda, K. Chin. J. Catal., 2017, 38, 1918.
187
P95: Cyclometalated Ir(III) Complexes as Probes for DNA Mismatches and Abasic Sites
P. David Dayanidhi, and V.G. Vaidyanathan*
Advanced Materials Laboratory, CSIR-Central Leather Research Institute, Adyar, Chennai 600 020.
Damage to our genetic material occur very often from various sources. Formation of DNA defects is
the initial step in tumor growth. Among various defects, the formation of thermodynamically unstable
sites such as mismatches and abasic sites are of great importance as failure in repair of these defects
results in mutagenesis. While errors during DNA replication give rise to mismatch base pairing,
cleavage of glycosidic bond by hydrolysis between a nitrogenous base and a 2‟-deoxyribose due to
exposure to UV radiation and other sources leads to the formation of abasic sites.1,2
Design of
molecules that target specific defects in DNA is of prime importance in order to prevent mutations. It is
found that metal-complexes can selectively recognize these defects by insertion of the planar ligand
into the defected site. Here, we present three Ir(III) complexes, [Ir(ppy)2(imiphen)]+ (1),
[Ir(ppy)2(furphen)]+ (2), and [Ir(ppy)2(faqphen)]
+ (3), where 1 selectively recognizes Ab:T and CA
mismatch, 2 recognizes Ab:G and 3 recognizes TT mismatch.
References:
1. Dahlmann, H. A.; Vaidyanathan, V. G.; Sturla, S. J. Biochemistry 2009, 48 (40), 9347.
https://doi.org/10.1021/bi901059k.
2. Boynton, A. N.; Marcélis, L.; Barton, J. K. [Ru(Me4phen)2dppz]2+, a Light Switch for DNA
Mismatches. J. Am. Chem. Soc. 2016, 138 (15), 5020. https://doi.org/10.1021/jacs.6b02022.
Fig: a) Structures of [Ir(ppy)2(L)]+; b) DNA sequences used in this study
188
P96: An Efficient, Heterogeneous Cu(I)-SBA Catalyzed One Pot Synthesis of 3,4-
Dihydropyrimidin-2(1H)-Ones
M. Thennila1,2
, S. Muthumanickam1, M. Sivabharathy
2, K. Selvakumar
1*
1 Research Department of Chemistry, Thiagarajar College, Madurai, Tamil Nadu, 625 009, India
2 Department of Physics, Sethu Institute of Technology, Kariapatti, Tamil Nadu, 626 115, India
The catalytic application of Cu(I) incorporated ordered mesoporous silica SBA-15 (Cu(I)-SBA-15) has
been evaluated for one‐pot Biginelli reaction for synthesizing 3,4-dihydropyrimidine-2-(1H)-ones. The
3,4-Dihydropyrimidin-2(1H)-One (DHPM) unit is present in various biologically active molecules and its
derivatives exhibit a wide range of pharmacological properties such as antiviral, antimitotic, anticarcinogenic,
antihypertensive etc. The catalyst was prepared first time by alcothermal strategy using P-123 as
surfactant. The morphology and porosity of the catalyst were then characterized by SEM, TEM,
SAXS, XRD and BET analysis. The performance of the Cu(I)-SBA-15 catalyst was investigated in the
Biginelli reaction with variety of halide/phenyl substituted aldehydes, alkylacetoacetates and
urea/thiourea under room temperature conditions. The catalyst exhibited excellent activity provided
corresponding Biginelli products in good to excellent yields. The reactivity, reusability and stability of
the catalyst were also investigated under the optimum reaction conditions
.
Scheme 1: Biginelli reaction using Cu(I)-SBA catalyst.
Reference:
1. Zhu, Y.; Huang, S.; Wan, J.; Yan, L.; Pan, Y.; Wu, A, Org. Lett. 2006, 8, 12, 2599.
2. Chandak, H. S.; Lad, N. P.; Upare , P. P. Catalysis Letters, 2009, 131, 469.
3. Dharma Rao, G.B.; B. Anjaneyulu, Kaushik, M. P., RSC Adv., 2014, 4, 43321.
189
P97: Development of Acrylonitrile-based Turn-on Fluorescence Chemosensor for Cyanide ion
Determination
Pranati Somkuwar, Shital Mohurle, and Ashok Kumar S.K*
Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore.
A new acrylonitrile-based turn-on fluorescence chemosensor (L) was developed by reacting 9-ethyl-
9H carbazole-3-carbaldehyde with 2-(benzo[d]thiazol-2-yl) acetonitrile. The sensing ability of receptor
L was studied by using colorimetric, spectrophotometric and spectrofluorimetric methods. The ligand
L shows highest selectivity towards CN- ions in terms of turn-on fluorescence response at 475 nm
upon the excitation at 350 nm. The fluorescence spectral study reveals that the formation of 1:1
stoichiometry complex between L and CN- with an estimated association constant of 2.04 ×10
5 M
-1 by
chemodosimetric mechanism. The L could detect CN- ions down to 1.48 nm without interfering from
other common interfering ions. Further, the binding mechanism of L was studied by using 1H NMR,
ESI-Mass and theoretical studies.
References:
1. Y. K. Yue, F. J. Huo, C. X. Yin, J. B. Chao and Y. B. Zhang, Sens. Actuators, B, 2015, 212,
451.
2. S. S. Razi, R. Ali, P. Srivastava and A. Misra, Tetrahedron Lett., 2014, 55, 1052
3. B. Vennesland, E.E. Comm, C.J. Knownles, J. Westly, F. Wissing, Cyanide in Biology,
Academic Press, London, 1981.
4. R. Takano, The treatment of leprosy with cyanocuprol, J. Exp. Med. 24 (1916)207–211.
190
P98: Bioinorganic Chemistry of Co(II) and Mn(II) complexes
V.K. Srivastava
Department of Chemistry D.S. College, Aligarh UP (India)
Schiff bases containing penicillin and heterocyclic structural units with N,N, donor atoms are
considered the most prominent research area in the field of coordination chemistry [1-6]. The
various donor atoms in them offer special ability for binding metals. Schiff base change the
physiological, morphological and Pharmacological activities of the compounds. Schiff base
complexes have been used as drugs and have valuable antibacterial antifungal, anti-
inflammatory and antitumor activities. A large number of Schiff bases and their complexes
have been studied for their interesting and important properties e.g. their ability to reversibly
bind oxygen, catalytic activity in hydrogenation of olefins and transfer of an amino group
photochromic properties. The high affinity for the chelation of the Schiff bases towards the
transition metal ions is utilized in preparing their solid complexes. In the present paper the
Co(II) and Mn(II) complexes were synthesized with Schiff base ligand 2- Thio phenyl glyoxal
anthranilicacid (TGAA). The coordination behavior of the ligand towards transition metal
irons was fully investigated by various spectral techniques. Biochemical Behavior of the
complexes were evaluated by antimicrobial, Enzyme inhibition activity and cytotoxic studies.
191
P99: Redox Switching of First Hyperpolarizability of Ru Based Metal Complexes
Karthika, C.1, P. K. Das
1
1Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012,
India
Organotransition metal complexes are promising in the field of molecular switches and opto-electronic
devices due to their structural stability in two different oxidation states and large second harmonic
response. Metal complexes with different second harmonic responses in different states have been
considered for data storage applications. Tuning of second harmonic response or the molecular level
property, β, electrochemical switching gained maximum attention due to minimum structural relaxation
caused by direct oxidation/reduction of the metal centre. Here we report two Ru based bimetallic
complexes, [NC-Ru-(bpy)2-CN-Ru(bpy)2-CN](PF6) (1) and [Ru(bpy)2-bptz-Ru(bpy)2](PF6)2 (2)1and
investigated their second harmonic generation after sequential oxidation/reduction of the Ru centre(s)
electrochemically. We have determined from cyclic voltammetry (CV) that the first oxidation of 10
to
1+1
occurs at +0.75 V and the second oxidation1+1
to 1+2
at +1.34 V. Similarly, the CV of the 2
complex shows that the first oxidation of 20 to 2
+1occurs at a much higher potential of + 1.95 V and the
second oxidation to 2+2
at +2.2 V. The spectro-electrochemical studies suggest that the mixed-valent
(MV) state of both the complexes exhibit an IVCT band in the infrared around ~1200 nm, which is
assigned to the metal-metal charge transfer from Ru (II) to Ru(III) states. In-situ second harmonic light
scattering (SHLS) experiments were carried out in a customized electrochemical cell, where the SH
intensity was measured with respect to a particular oxidation state.2 The MV state possess 3 times
higher β value compared to the other states of the complexes, which are perhaps due to resonance
enhancements mediated by the IVCT band at the incident wavelength (1064 nm) and the MLCT band
at SH wavelength (532 nm).
Figure 1: Structure of complex 1 and 2
References:
1. Bignozzi, C. A.; Roffia, S.; Chiorboli, C.; Davila, J.; Indelli, M. T.; Scandola, F. Inorg.
Chem.1989, 28 (24), 4350–4358.
2. Karthika, C.; Sarath Kumar, S. R.; Kathuria, L.; Das, P. K.; Samuelson, A. G.. Phys. Chem.
Chem. Phys.2019, 21 (21), 11079–11086.
192
P100: Development Of Novel Ru(II), Ir(III) and Ru(II)-Ir(III) Mix metal Complexes and their cancer
theranostics application
Prithivi Moharana,. Priyankar Paira
Department of Chemistry (SAS), Vellore Institute Of Technology,Vellore-14, India
The perilous impact of cancer is now a matter of great frightening to us after the heart disease.
Although the discovery of platinum based drug, cisplatin initiated the use of metallodrug in cancer
therapy but its several drawbacks are diminishing its use nowadays. While, ruthenium and iridium
based drugs are now being exploited as better substitute of cisplatin due to their good cytoselectivity,
target specificity, aqueous solubility, and good fluorescent property. Therefore presence of ruthenium
and iridium metals together in a same moiety reinforce the drug to be more selective and useful in
invivo imaging giving fluorescent emission at NIR region. Embroidered polynuclear transition metal
based heterodimetallic complexes with appropriate ligand framework often combine properties of
individual metals into the same unit and allow cooperative interaction which leads to enhanced
properties and biological activities as compared to their monometallic counterparts.
References:
1. Lobo, N. A.; Shimono, Y.; Qian, D.; Clarke, M. F.; Annu. Rev. Cell Dev. Biol., 2007, 23, 675
193
P101: Polyvinylidene Fluoride/Aliphatic Hyperbranched Polyester (Generation-3) Electrospun
Nanoweb based Piezoelectric Sensors
Priyanka Yadava,P.Lakshmi praba
a, R. Gunasekhar
a, B. Indumathy, M.S. Reza
b, Hongdoo Kim
b,**, A.
Anand Prabua,*
aDepartment of Chemistry, School of Advanced Science, Vellore Institute of Technology, Vellore
632014, Tamil Nadu, India bDepartment of Advanced Materials Engineering for Information & Electronics, Kyung Hee University,
Gyeonggi-do 17104, Korea
In the present study, aliphatic hyperbranched polyester of 3rd
generation (Al-HBP-G3) was
synthesized using pentaerythritol (PE) as core and dimethylol propionic acid (DMPA) as aliphatic
monomer by one-shot melt-polycondensation method (140 oC, 20 h, N2 atm.). Though the synthesis
methodology is already reported [1], we studied the effect of reduced pressure at regular intervals on
the Al-HBP-G3 reaction kinetics, which is unreported so far. Samples collected at regular intervals of
time were analysed using FT-IR, NMR (H1 & C
13) and thermal analyses (DSC, TGA) for optimizing the
reaction conditions and for understanding the structural changes during HBP formation as a function
of reaction time. Further, electrospinning was done with neat PVDF and its blends with Al-HBP-G3 (0,
10, 20, 30 and 40 wt.% of HBP w.r.t. PVDF) under controlled electrospinning conditions. The
nanoweb samples were analysed using FT-IR and XRD, which showed increasing β-crystallinity in
PVDF with increasing HBP content which is an evidence that piezoelectric sensors with higher output
voltage can be possibly achieved using PVDF/HBP blends than that achieved using neat PVDF.
Piezoelectric sensors fabricated using the nanoweb samples were subjected to dynamic pressure (1
kgf, 1.0 Hz) condition and their piezoelectric output signals were analysed to optimize the PVDF/HBP
content under the measured conditions [2,3].
References:
1. D.M. Dhevi, A.A. Prabu, H. Kim, M. Pathak, J. Polym. Res., 21(7), 1-9 (2014).
2. P. Sathiyanathan, A.A. Prabu, K.J. Kim, Macromol. Res., 24, 670-674 (2016).
3. G. Prasad, P. Sathiyanathan, A.A. Prabu, K.J. Kim, Macromol. Res., 25, 981-988 (2017).
194
P102: Polyvinylidene Fluoride/Aliphatic Hyperbranched Polyester (Generation-1) Electrospun
Nanoweb based Piezoelectric Sensors
P. Lakshmi Prabaa, Priyanka Yadav
a, R. Gunasekhar
a, B. Indumathy, M.S. Reza
b, Hongdoo Kim
b,**, A.
Anand Prabua,*
aDepartment of Chemistry, School of Advanced Science, Vellore Institute of Technology, Vellore
632014, Tamil Nadu, India bDepartment of Advanced Materials Engineering for Information & Electronics, Kyung Hee University,
Gyeonggi-do 17104, Korea
In the present study, aliphatic hyperbranched polyester of 1st generation (Al-HBP-G1) was
synthesized using pentaerythritol (PE) as core and dimethylol propionic acid (DMPA) as aliphatic
monomer by one-shot melt-polycondensation method (140 oC, 20 h, N2 atm.). Though the synthesis
methodology is already reported [1], we studied the effect of reduced pressure at regular intervals on
the Al-HBP-G1 reaction kinetics, which is unreported so far. Samples collected at regular intervals of
time were analysed using FT-IR, NMR (H1 & C
13) and thermal analyses (DSC, TGA) for optimizing the
reaction conditions and for understanding the structural changes during HBP formation as a function
of reaction time. Further, electrospinning was done with neat PVDF and its blends with Al-HBP-G1 (0,
10, 20, 30 and 40 wt.% of HBP w.r.t. PVDF) under controlled electrospinning conditions. The
nanoweb samples were analysed using FT-IR and XRD, which showed increasing β-crystallinity in
PVDF with increasing HBP content which is an evidence that piezoelectric sensors with higher output
voltage can be possibly achieved using PVDF/HBP blends than that achieved using neat PVDF.
Piezoelectric sensors fabricated using the nanoweb samples were subjected to dynamic pressure (1
kgf, 1.0 Hz) condition and their piezoelectric output signals were analysed to optimize the PVDF/HBP
content under the measured conditions [2,3].
References
1. D.M. Dhevi, A.A. Prabu, H. Kim, M. Pathak, J. Polym. Res., 21(7), 1-9 (2014).
2. P. Sathiyanathan, A.A. Prabu, K.J. Kim, Macromol. Res., 24, 670-674 (2016).
3. G. Prasad, P. Sathiyanathan, A.A. Prabu, K.J. Kim, Macromol. Res., 25, 981-988 (2017).
195
P103: Stabilization of collagen using amine functionalized TiO2 nanoparticles
S. Nagaraj, P. Thanikaivelan*
Advanced materials laboratory CSIR-Central Leather Research Institute, Adyar, Chennai 600020
Crosslinking proteins such as collagen using physical and chemical methods offers an enhanced
thermal stability and mechanical properties.1 Being a biomolecule, adopting nanotechnology for
crosslinking the collagen would provide additional advantages in realizing its usage in the perspective
of both biomedical and industrial application.2 In this work, we report a method to stabilize collagen
fibres by using 3-aminopropyltriethoxysilane (APTES) functionalized TiO2 nanoparticles via a method
utilizing N-hydroxysuccinimide (NHS) and 1‐ethyl‐3‐(dimethylaminopropyl)carbodi‐imide (EDC). NHS
and EDC together activate the carboxylic acid groups of collagen to give O-acylisourea groups, which
will react with terminal amino groups of APTES functionalized TiO2 nanoparticles. Powder X-ray
diffraction (XRD), scanning electron microscopy (SEM) and 13
C-nuclear magnetic resonance spectra
(13
C-NMR) were the characterization techniques carried out for TiO2 and APTES functionalized TiO2
nanoparticles. APTES functionalized TiO2 nanoparticle crosslinking increases the hydrothermal
stability of collagen measured by using differential scanning calorimetry (DSC) ⁓ 85 °C suggesting
that functionalized nanoparticle is able to improve thermal stability of collagen fibres. Circular
dichroism and FT-IR spectra revealed that there is no alteration in the secondary structure of collagen
fibers on the treatment with functionalized nanoparticles. Hence, we propose the use of APTES
functionalized TiO2 nanoparticles for the effective crosslinking of collagen fibres.
References:
1. Ma, L.; Gao, C.; Mao, Z.; Zhou, J.; Shen, J., Biomaterials 2004, 25 (15), 2997-3004.
2. Nagaraj, S.; Easwaramoorthi, S.; Rao, J. R.; Thanikaivelan, P., International journal of
biological macromolecules 2019, 131, 779-786.
196
P104: Di- and Trinuclear Pt(II) Complexes of Pyridinyl Benzimidazole Ligands as Anticancer
Agents: Effect of Nuclearity and Ancillary Ligands
N. U. Prajith and V. Alexander*
Department of Chemistry, Loyola College, Chennai 600034, India
The lipophilicity and anticancer activity of the dinuclear platinum(II) complexes [(Am-py)2Pt--(L1)-
Pt(Am-py)2](ClO4)4 (1) and [(HO-py)2Pt--(L1)-Pt(HO-py)2](ClO4)4 (2) and the trinuclear complexes
[((Am-py)2Pt)3-3-(L2)](ClO4)6 (3) and [((HO-py)2Pt)3-3-(L2)](ClO4)6 (4) of the pyridinyl benzimidazole
ligands L1 and L2 and their dependence on the nature of ancillary ligands and nuclearity are
reported. The complexes 2 and 4 containing 3-hydroxypyridine are more hydrophilic than 1 and
3 containing 4-aminopyridine ancillary ligand and the logPo/w value decreases with increase in
nuclearity. The dinuclear complexes 1 and 2 demonstrate higher cytotoxicity (IC50 values 24–29 and
29–34 M, respectively) on the HeLa, MCF-7, and HepG2 cell lines than the trinuclear complexes 3
and 4 (IC50 values 39–48 and 46–58 M, respectively). The IC50 values of the complexes 1-4 on Vero
cell line are 47, 51, 65, and 72 M, respectively. The complexes induce cell cycle arrest in the G0/G1
phase. The ethidium bromide/acridine orange dual staining assay indicates both apoptotic and
necrotic cell death while annexin V-alexa fluor 488/propidium iodide apoptosis assay shows necrotic
pathway of cell death. The dinuclear complexes 1 and 2 trigger necrosis at lower concentration, while
at higher doses apoptotic mode of cell death is observed. The trinuclear complexes 3 and 4 prompt
necrotic mode of cell death in a dose dependent manner.
Annexin V-Alexa fluor488/PI Assay
Cytotoxicity
EB/AO dual staining assay
1 2 3 4
197
P105: Phase Formation and in-Vitro bioactivity evaluations of Zinc and Silver co-substituted
Strontium Phosphosilicate composites for Orthopaedic applications
Chetan, U. Vijayalakshmi*
Department of Chemistry, School of Advanced Sciences,Vellore Institute of Technology, Vellore,
Tamil Nadu, INDIA.
The exploitation of structural biocompatible features of apatite coupled with antibacterial properties of
inorganic dopants forms basis of the study.[1]
Synthesis of Zinc and Silver co-substituted Strontium
phosphosilicate was attempted in a low pH acidic medium with an equal concentration of dopants
increasing hierarchically for structural and Biological evaluations. Aqueous Sol-Gel technique ensured
proper reactivity in the reaction mixture.[2]
The acidic medium was found to be more applicable on
account of the isoelectric point of silica leading to formation of secondary Sr2SiO4 phase apart from
Sr2P2O7. Sintering formed stable crystalline phases evident from diffraction data showing very little
change in spectra confirming proper incorporation of dopants at respective lattice sites. Infrared
spectroscopy Identification of characteristic bands in infrared spectra confirmed the integrity of crystal
lattice with minor changes over substitution. The morphological features showed minimal differences
from the parent material. Biological evaluations showed the successful seeding of amorphous apatite
within two days of SBF immersion and the antibacterial properties were enhanced upon incorporation
of Zinc and Silver as compared to pure phase. Moreover, MTT assay of samples with MG-63 Cell
lines showed proper cytocompatibility at low release concentration that decreases with an increase in
release concentration of samples.[3]
References:
1. Shen, Y., Tok, A. and Dong, Z. Journal of the American Ceramic Society, 2010, 93, 1176–
1182.
2. Daniel Arcos, María Vallet-Regí, Acta Biomaterialia, 2010, 6, 2874–2888
3. Fu YF, Chen DM.. Journal of Oral Tissue Engineering. 2005,2(2),76-80
198
P106: Piezoelectric Sensors based on Electrospun PVDF and its Blends with Aromatic
Hyperbranched Polyester
Pulak Pratik Ganesha, R. Gunasekhar
a, B. Indumathy
a, M.S. Reza
b, Hongdoo Kim
b,**,A. Anand
Prabua,*
a Department of Chemistry, School of Advanced Science, Vellore Institute of Technology, Vellore
632014, Tamil Nadu, India b
Department of Advanced Materials Engineering for Information & Electronics, Kyung Hee University,
Gyeonggi-do 17104, Korea
In this study, aromatic hyperbranched polyester of first generation (Ar-HBP-G1) was synthesized
using solution polycondensation of pentaerythritol (PE) as core molecule, diphenolic acid (DPA) as
monomer and DMF as solvent at 130 °C for 23 h under inert atmosphere. The synthesized Ar-HBP-
G1 was characterized using spectral (FTIR-ATR, NMR) and thermal analyses (DSC, TGA). Reaction
kinetics studied using FTIR data was used to optimize the polymerization conditions. Further,
electrospinning of neat PVDF and its blends with Ar-HBP-G1 as a function of varying HBP content (0,
10, 20, 30 and 40 wt.-% of Ar-HBP w.r.t. PVDF content) were carried out under controlled
electrospinning conditions, and studied for their crystallization behaviour using FTIR and XRD
analysis. FTIR quantitative analysis showed higher β-crystallinity in PVDF with increasing Ar-HBP
content which is a favourable condition for fabricating high performance piezoelectric sensor devices.
Electrospun nanoweb samples were measured for their piezoelectric output signals under applied
pressure of 1 kgf and released periodically at 1.0 Hz. Among the four samples, PVDF/HBP-G1
(90/10) sample exhibited higher peak-to-peak (Vp-p) piezoelectric output signal (+6.42 V) than neat
PVDF (+0.95 V), PVDF/HBP-G2 (90:10) (+4.03 V) and PVDF/HBP-G3 (90:10) (+4.13 V).
Piezoelectric signals were also measured by varying load and frequency of the sensor, which showed
increasing output voltage compared to neat PVDF. From the Vp-p data, it can be concluded that the
addition of Ar-HBP to PVDF plays a vital role in improving its piezoelectric characteristics, which
signifies the importance of this study. Acknowledgement: The authors (R.G. and A.A.P) wish to
thank CSIR, Government of India for supporting this study under CSIR-EMR-II scheme
(03(1450)18/EMR-II dt.05-06-2018). A.A.P also thank VIT for providing „VIT SEED GRANT‟ for
carrying out this research work.
References:
1. D.M. Dhevi, A.A. Prabu, H. Kim, M. Pathak, J. Polym. Res., 21(7), 1-9 (2014).
2. P. Sathiyanathan, A.A. Prabu, K.J. Kim, Macromol. Res., 24, 670-674 (2016).
3. G. Prasad, P. Sathiyanathan, A.A. Prabu, K.J. Kim, Macromol. Res., 25, 981-988 (2017).
199
OH
Br
Br
OH
BrBr
O
S
O
O
Br
Br
OH
BrBr
SO
O OO-
P107: What makes „Bromophenol Blue‟ YELLOW in Methanol?
V. Sabareesh1,*, Aaheli Ghosh
2, Adrita Das
2 and Agniruudrra Sinha
2
1.Advanced Centre for Bio Separation Technology (CBST),
2.School of Bio Sciences and Technology (SBST),Vellore Institute of Technology (VIT), Vellore, Tamil
Nadu – 632 014, India.
Bromophenol Blue (BPB) is a widely and routinely used dye in gel electrophoretic experiments for
nucleotide and protein analysis. It is also used as an acid-base indicator to monitor pH variations in
aqueous solutions. In aqueous solutions, BPB can exist in two forms: neutral or anionic form (Figure
1).1 While, several studies involving BPB have been carried out in aqueous solutions, only a few
investigations have been done in organic solvents. Therefore, we wanted to perform solvatochromic
experiments in different organic solvents, such as, methanol, acetonitrile and acetone. For the sake of
comparison, UV-Visible spectroscopic data were also acquired in water at near-neutral pH (pH ~ 6).
Interestingly, we found that BPB in organic solvents appear as „Yellow-color‟, whereas it gives blue
color in water (pH ~ 6).
Neutral Form (Ring-Closed) Anionic Form (Ring-Opened)
To corroborate this color change, we surmise or hypothesize that BPB might exist in neutral ring-
closed form in organic solvents, whereas the ring-opened anionic form is responsible for it to be in
blue color in water (pH ~ 6). To test this hypothesis, we chose to do experiments using mass
spectrometry (MS), in particular, of electrospray ionization (ESI) based, since it is possible to
unambiguously determine „intact molecular mass‟ (without or negligible molecular fragmentation) by
ESI-MS. Not only intact molecular mass, but it is also possible to obtain information regarding the
number of charges on the molecule, through ESI MS. Thus, ESI - MS data were acquired separately
for BPB solution prepared in methanol and BPB solution dissolved in water (pH ~ 6). The data were
recorded in both positive and negative ion modes and the samples were introduced into the mass
spectrometer (Quattro Premier XE, Waters) by direct infusion method. The ESI-MS data indicate that
the transition from the „blue color to yellow color‟ of BPB upon changing the solvent from water to
methanol may not be due to change from its ring-opened anionic form to ring-closed neutral form. In
other words, charge on the BPB molecule may not be contributing for its solvatochromic behaviour in
the solvents that have been chosen in this study. Further studies are underway for applying other
spectroscopic techniques such as Infrared spectroscopy and Nuclear Magnetic Resonance
spectroscopy to understand, which form of the molecular structure is responsible for the yellow color
of BPB in methanol.
Reference:
1. Madusudan; Vijayan M. Protein Engineering, Design and Selection 1992, 5, 399-404.
200
P108: Development of novel Ruthenium (II) and Iridium (III) based monometallic, bimetallic and
heterobimetallic scaffolds for theranostic application in treatment of cancer
Nilmadhab Roy, Priyankar Paira
Department of Chemistry, School of Advanced Sciences, VIT, Vellore-632014, Tamilnadu, India
We are in a great menace due to unrestricted increase of third most fatal disease, cancer as we are
still unable to discover appropriate medicine to defeat cancer permanently. Although there are some
market available drugs, they are associated with lots of demerits in treatment of cancer and thereby
they are gradually losing their importance. From that point of view, our main objective is to find out the
suitable medicines capable of diagnosing as well as killing of cancer cells and thus we have aspired
to develop i) target specific, ii) cytoselective rendering the normal cell unaffected, iii) water soluble, iv)
cancer cell permeable, v) luminescent drug to get rid from the grip of cancer by using the drug
theranostically, i.e. detection and destruction of cancer cell simultaneously. In order to achieve our
goal, we have tried to prepare novel Ru(II) and Ir(III) based bi metallic and hetero bimetallic drugs in
our laboratory using environmentally benign “Green Methodology” in treatment of cancer
theranostically. The interesting feature of our scaffolds are the presence of two different metals in a
same moiety which can fulfill both the requirements of detection and destruction of cancer cell by
using only one drug at a time as the attachment of iridium metal makes the scaffold more fluorescent
by shifting the emission wavelength to NIR region and compels the scaffolds to act as a good
anticancer agent along with the presence of ruthenium metal. It is noteworthy that we already
succeeded upto in vitro study with that scaffolds and hope it will help in cancer treatment and will act
as live cell imaging probe in near future due to having excellent anticancer activity with good
fluorescent property.
References:
1. Subran S. K., Banerjee S., Mondal A., Paira P., New J. Chem., 40, (2016), 10333.
2. Sarkar B, Mondal A, Madaan Y, Roy N, Moorthy A, Kuo YC, Paira P, Dalton Transactions
(2019), 48 (32), 12257-12271
3. Mondal A., De S., Maiti S., Sarkar B., Sk A. K., Jacob R., Moorthy A., and Paira P.,Journal of
Photochemistry and Photobiology B: Biology, Vol. 178, (2018), pp 380-394.
201
P109: Simple analytical method for the estimation of six potential genotoxic impurities in
Tenofovir disporxil maleate drug using GC-MS technique
S. Elumalai, S.Senthilkumar*
Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology (VIT),
Vellore–632014.
Tenofovir disoproxil maleate is an oral prodrug of Tenofovir, which is a nucleoside reverse
transcriptase inhibitors (NRTIs) with activity against retroviruses, including HIV-1 & 2 and
Hepadnaviridae. Six potential impurities, viz., ethyl bromide, chloromethyl methyl carbonate,
chloromethyl ethyl carbonate, chloromethyl n-propyl carbonate, dichloromethyl isopropyl carbonate
and chloromethyl-N,N-diethyl carbamate have been scrupulously chosen from specific route of
synthesis and evaluated for their genotoxicity using LAZAR toxicity prediction in-silico model QSAR
prediction software, which were showing structural alert for genotoxicity, therefore chosen them this
study. These impurities are highly reactive in nature, and their detection and quantification were
always challenging as the maximum permissible daily dose is 5 ppm based on TTC and recovery was
also impacted because of the sample matrix interference. Therefore, the analytical technique
engaged should be versatile, simple, selective, cost effective yet accurate. In order to overcome
these challenges, we developed an analytical methodology using a hyphenated analytical technique
(GC-MS) with easy sample extraction procedure (to overcome the matrix interference). The detection
limits of each impurity arrived using this method was around 0.07 ppm whereas the quantification
limits were approximately around 0.21 ppm. The method was linear over quantification limit to about
7.0 ppm (i.e., 120% of the actual limit). This method was fully validated in compliance with ICH Q2 R1
requirement with the parameters of system suitability, specificity, linearity, LOD, LOQ, method
precision, intermediate precision and robustness.
202
P110: Development of a Calcium Phsophatebased Bone Adhesive which Aims to Repair
Cranofacial Fractures
Nidhi Nair
Department of Bioscinces, School of Biosecienceand Technology,Vellore Institute of Technology
Vellore–632014.
Conventional bone adhesives often used bone bonding agents to adhere the bone fragments
together. Bone adhesives used earlier had higher mechanical strength but lower biocompatibility. The
introduction of calcium phosphate based bone cements opened possibilities for adhesives which
mimic the natural bone environment. This study aims to form a calcium phosphate based bone
adhesive consisting of polydopamine and oxidised guar gum which has improved mechanical and
cytocompatible properties. This also strives to overcome the impediment of the brittle nature of
calcium phosphate cements. The final calcium phosphate cement has better anti-washout property
and faster setting time owing to guar gum. Formation of hydroxyapatite when polydopamine is added
to the calcium phosphate powder helps to increase the compressive strength of the cement as well as
acts as a precursor for the effective regeneration of the bone.
203
Figure 1: Plot of G′ or G″ (Pa) vs (rad/sec) for
HPC-Iodine hydrogel in presence of borax
Figure 2: Plot of G′ or G″ (Pa) vs (rad/sec) for
HPC-Iodine hydrogel
P111: Rheological behaviour of hydroxypropylcellulose (HPC) hydrogel in the presence of
surfactant
N. Shubhaschandra Singh
Department of Chemistry, D.M College of Science, Imphal , Dhanamanjuri University Manipur
Hydroxypropylcellulose (HPC) (nonionic water soluble polymer) readily forms hydrogel with iodine [1].
HPC-iodine hydrogel was found to be enhances gelling process on the addition of
sodiumdodecylsulphate (SDS) (anionic surfactant). The addition of borax in the HPC-iodine hydrogel
exhibited as a stronger hydrogel [2, 3] with G′ greater than G″ throughout the experimental frequency
range than the HPC-iodine hydrogel in presence of SDS (Figure 1). The behaviour is explained by the
preferential occupation of the active sites of the HPC by the borax through di-diol complexation [2-5].
Therefore, borax has shown comparatively higher affinity towards HPC than both SDS and iodine
(Figure 2). DSC profiles of the HPC-iodine hydrogels also support the proposition of preferential
occupation of the active site of HPC despite showing lower gel melting point temperature.
References:
1. Homendra, N.; Shubhaschandra, S.N., J. Phys. Chem.B 2007, 111, 4098-4102
2. Tayal, A.; Pai, V.B.; Khan, S.A., Macromolecules 1999, 32, 5567-5574.
3. Carlsson, A.; Karlström, G.; Lindman, B., Colloids and Surfaces 1990, 47, 147-165.
4. Deguchi, S.; Kuroda, K.; Akiyoshi, K.; Lindman, B.; Sunamoto, J., Colloid and Surface
A:Physicochemical and Engineering Aspects 1999, 147, 203-211.
5. Khutoryanskiy, D.V.V.; Cascone, M.G. ; Lazzeri, L.; Barbani, N.; Nurkeeva, Z.S.; Mun G. A.
Dubolazov, A.V., Polymer International 2004, 53, 307-311.
204
P112: Facile Synthesis of Quasi-spherical, Hexagonal and Triangular Silver Nanoparticles at
Room Temperature
Salima Begum, R.K. London Singh*
Department of Chemistry.D.M. College of Science, Dhanamanjuri University, Manipur.
)
Rapid and stable green synthesis of silver nanoparticles at room temperature is still a challenge to the
nanotechnologists. Amongst the metal nanoparticles, silver nanoparticle is most attracted.1 Synthesis
of silver nanoparticles using gallic acid as reducing agent and starch as stabilising agent at room
temperature is reported in this paper. UV-visible studies confirmed the formation of silver
nanoparticles by the appearance of surface plasmon resonance (SPR) band at 443 nm and found
stable for months. XRD studies revealed the formation of face centre cubic structure of silver crystal
with preferential orientation along (111) plane with crystallite size of 9.32 ± 1.31 nm. TEM image
showed the formation of quasi-spherical, highly facet hexagonal silver nanoplates and triangular silver
nanoparticles. EDX analysis confirmed the Ag crystal by the presence of energy peak at 3 eV.
Stabilisation of the nanoparticles with starch is supported by FTIR analysis. The synthesised silver
nanoparticles showed catalytic activity in the degradation of crystal violet (CV) with sodium hydroxide
and finds potential application in the removal of toxic dye from industrial effluents and environment.2
Figure 1: SPR of starch-stabilised AgNPs Figure 2: TEM micrograph of synthesised AgNPs
Figure 3: Catalytic degradation of CV with NaOH in the presence of starch-stabilised AgNPs
References:
1. Sharma, K.; Singh, G.; Kumar, M.; Bhalla, V. RSC Adv., 2015, 5 (33), 25781–25788
2. Goswami, M.; Baruah, D.; Das, A.M. New J. Chem., 2018, 42, 10868-10878
205
P113: Sierpiński triangle to pyramid via concerted interplay of weak interactions
Rajarshi Sarkar*,a,g
Tingzheng Xie,a Kevin J. Endres,
b Wang Zilu,
a Charles N. Moorefield,
c Mary Jane
Saunders,d Anil K. Patri,
e Chrys Wesdemiotis,
b* Andrey V. Dobrynin,
George R. Newkome
a,b,f*
Depts of aPolymer Science and
bChemistry, The University of Akron, Akron, Ohio 44256 USA;
cDendronex LLC, 109 Runway Drive, Lubbock, Texas 79416 USA;
dDepartment of Biological
Sciences, Florida Atlantic University, Boca Raton, Florida 33431 USA; eNCTR-ORA Nanotechnology
Core Facility, National Center for Toxicological Research, U.S. Food & Drug Administration, HFT-30,
3900 NCTR Road, Jefferson, Arkansas 72079 USA; fCenter for Molecular Biology and Biotechnology,
Florida Atlantic University, 5353 Parkside Drive, Jupiter, Florida 33458 USA, gSVKM‟S NMIMS Indore,
Super Corridor Rd, Gandhi Nagar, Indore, Madhya Pradesh 452005
:
We have demonstrated that self-assembled Sierpiński triangle with alkylated corners undergoes
further self-assembly to produce megastructural Sierpiński pyramids, driven by the facile lipophilic-
lipophilic association and complementary perfect-fit of building blocks. The formation of such 2D & 3D
structures were verified by combination of the microscopic and multiscale simulation techniques.
Figure caption/Scheme: Self-assembly of Sierpiński pyramid
References:
1. Daum, B.; Quax, T. E. F.; Sachse, M.; Mills, D. J.; Reimann, J.; Yildiz, Ö.; Häder, S.;
Saveanu, C.; Forterre, P.; Albers, S.-V.; Kühlbrandt, W. Proc. Natl. Acad. Sci. 2014, 111,
3829.
2. Sarkar, R.; Guo, K.; Moorefield, C. N.; Saunders, M. J.; Wesdemiotis, C.; Newkome, G. R.
Angew. Chem. Int. Ed. 2014, 53, 12182.
3. Sarkar, R.; Guo, Z.; Li, J.; Burai, T. N.; Moorefield, C. N.; Wesdemiotis, C.; Newkome, G. R.
Chem. Commun. 2015, 51, 12851.
206
P114: Imidazolium ionic liquids towards the Mg/S batteries
Santosh N. Chavan1*
, and Vatsala Rani J. 1*
Polymer and Functional Material Division 1 Indian Institute of Chemical Technology Hyderabad, Hyderabad, India
Rechargeable magnesium (RMB) battery has been promising candidate1,2
for future battery
generation due to its safety Mg anode. In this combination sulphur cathode is one of the safe, low-
cost and high volumetric electrochemical storage system.3,4
Electrolyte is one of the challenging task
in this system due to Mg compatibility and sulphur (polysulfide) solubility.1 Common anion used in
electrolyte system provides fast movement of [Mg2+
(BF4)n] and [(Mg2+
(TFSI-)n] adduct as well as
suppress the polysulfide solubility due to anion concentration. Effectively the passivation of Mg2+
,
intercalation into electrodes and transportation get enhanced. These effect truly exist into Mg2+
kinetics in the Mg/S batter cycling and conductivity results. The BF4- and TFSI
- WCA (weakly
coordinating anion) tuned with imidazolium ionic liquid and common anion Mg (BF4-)2 and Mg (TFSI
-)2
into Mg/S battery with sulphur cathode material. The fluorinated anionic ionic liquid prohibit the
dissolution of sulphur than the localized negative charge anionic ionic liquid and effectively enhance in
the suppressing polysulfide shuttle effect. This is shown by longer cycle capacity in full cell and
electrolytes are analysed after s by UV, electrode surfaces by SEM-XPS.
References:
1. Wang, P.; Buchmeiser, M. R. Adv. Funct. Mater., 2019, doi.org/10.1002/adfm.201905248.
2. Chavan, S. N.; Tiwari, A.; Nagaiah, T. C.; Mandal, D. Phys. Chem. Chem. Phys. 2016, 18,
16116.
3. Wang, J.; Lin, F.; Jia, H.; Yang, J.; Monroe, C. W.; NuLi, Y. Angew. Chem. Int. Ed. 2014, 53,
10099.
4. Kanakaiah, V.; Latha, M.; Sravan, B.; Palanisamy, A.; Rani, J. V. J. Electrochem. Soc. 2014,
161, A1586.
207
P115: Ionic Liquid-Immobilized Proline(s) Organocatalyst Catalysed One-Pot Multi-Component
Mannich Reaction under Solvent-Free Condition
Prabhakara M D, Barnali Maiti*
Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology VIT, Vellore–
632014.
A highly efficient clean and simple methodology has been established for the one-pot multi-
component Mannich reaction using ionic liquid immobilized proline(s) organocatalyst under solvent-
free conditions. The three-component comprising of substituted acetophenones substituted aromatic
aldehydes and substituted aromatic amines underwent Mannich reactions in one-pot in presence of 7
mol% of ionic liquid immobilized proline(s) organocatalyst to provide β-amino carbonyl compounds in
2-3 h at room temperature with excellent yields. This methodology delivers several advantages such
as short reaction time, mild reaction conditions, multi-component approach, transition metal-free, low
catalyst loading percentage, and solvent-free synthesis. The ionic liquid immobilized proline(s)
organocatalyst was recycled and reused six times without significant loss of its catalytic activity.
References:
1. Miao, W.; and Chan, T. H. Adv. Synth. Catal. 2006, 348, 1711.
2. Lisnyak, V. G.; Kucherenko, A. S.; Valeev, E. F.; Zlotin, S. G. J. Org. Chem. 2015, 80, 9570.
208
P116: Photoinduced Solvatochromic Properties and Biomacromolecular Interaction of New
Indazole Derivatives.
A.Roniboss, Kaushik Chanda, Balamurali MM*.
Chemistry Division.Vellore Institute of Technology,Chennai campus, Chennai,India.
Heterocyclic compounds obtained by diversity-oriented synthesis are widely found in natural products
and bioactive molecules and have a vast array of applications across numerous fields. Over the last
decade, researchers in drug discovery have paid more attention to indazole derivatives, as this moiety
acts as a bioisostere of indoles and benzimidazoles. Indazole derivatives scarcely occur in nature, but
molecules with 2H-indazole moieties have a wide range of biological properties, such as antitumor
activity, HIV-protease inhibition, anti-HIV activities, anti-inflammatory activity, modulation of estrogen
receptors and anti cancer activity, antifungal, antibacterial. Moreover, in addition to these biological
activities, indazole scaffolds also exhibit photophysical properties for potential theranostic
applications. Herein we discuss the various electronic properties based on the effect of substituents
and the ability of these derivatives to interact with biomacromolecules.
References:
1. Hu, F.; Szostak, M. Adv.Synth.2015, 357, 2583-2614.
2. Behrouz, S. J. Heterocyclic. Chem.2017, 54, 1863-1871.
209
P117: Determining the Role of Mechanical Strength on EMT using a Novel PVA-PEG-HAp 3-D
Scaffold
Simrit Safarulla1, Amit Kumar Jaiswal
2*
1School of Biosciences and Technology, VIT, Vellore-632014,
2Centre for Biomaterials, Cellular, and Molecular Theragnostic, VIT, Vellore-632014
Epithelial to mesenchymal transition (EMT) is the primary culprit of metastatic cancer. Recent
evidences show that sarcoma, a soft tissue cancer, also exhibits EMT like behaviour which results in
cancer cell invasion into the lymph nodes making the prognosis worse.1 EMT is influenced by its
microenvironment and one such property, tissue stiffness has been accepted as a cancer biomarker.2
This study is an attempt to elucidate the mechano-sensitivity of primary bone cancers in a 3-D bone
microenvironment. A polyvinyl alcohol/ poly ethylene glycol/ hydroxy apatite (PVA/PEG/HAp) scaffold
was prepared by 6 consecutive freeze-thaw cycles. PVA, PEG and HAp at 14%(wt./v), 6% (wt./v) and
20% (wt./wt.) showed impressive compressive strength of 24.07±12.06 MPa in dry conditions. The
swelling index and the qualitative degradation assay proved the water retention capability and stability
of the scaffold.
References:
1. Sannino, G.; Marchetto, A.; Kirchner, T.; Grünewald, T. G. P. Cancer Res. 2017, 77 (17),
4556 LP – 4561. https://doi.org/10.1158/0008-5472.CAN-17-0032.
2. Martinez, B.; Yang, Y.; Harker, D. M. R.; Farrar, C.; Mukundan, H.; Nath, P.; Mascareñas, D.
Frontiers in Cell and Developmental Biology . 2019, p 199.
210
P118: A comparative Catalytic Study of Hydrotalcite/SBA-15 Nanocomposites for the Efficient
Conversion of Biomass-derived Substrates
Marimuthu Manikandan, Ayyappan Arjunan, Palanivelu Sangeetha*
Chemistry Division, School of Advanced Sciences,Vellore Institute of Technology, Vandalur -
Kelambakkam road,Chennai – 600 127.
Hydrotalcites (HT) have a broad spectrum of applications as robust heterogeneous catalysts for
various chemical transformations.1 The reactivity of HT based catalysts can be tailored by introducing
siliceous material either into the internal framework or at the external framework. The modification on
the HT framework with silica based mesostructure that gives rise to the formation of versatile Lewis
base, Brønsted base and redox‐active catalytic sites.2 Understanding the nature and catalytic role of
such sites is crucial for guiding the design of new and improved HT/SBA-15 based nanocomposite
catalysts.3 This work presents the comparative evaluation on the catalytic performance of HT@SBA-
15 and SBA-15@HT for biomass conversion. The influence of the preparation methods, including
one-pot synthesis and post-synthetic intercalation, was examined. The textural and physicochemical
properties of synthesized materials have been evaluated by XRD, SEM, TEM, and CO2-TPD
characterization studies. Both composites exhibited distinct catalytic activity towards the conversion of
biomass derived substrates to fine chemicals. Characterization studies conferred that the fine-tuning
of basic sites on the nanocomposites has a vital role on the catalytic performance. The role of active
sites in addressing the structural features in nanocomposites and understanding reaction pathway
relations is discussed. Special attention is devoted to such reactivity phenomena as active site
cooperativity, catalyst multifunctionality as well as confinement‐enhanced multisite reactivity
commonly encountered in mesoporous catalysis.
Figure: Graphical representation of the comparative catalytic performance of hydrotalcite/SBA-15
nanocomposites
References:
1. Manikandan, M.; Prabu, M.; Ashok Kumar, S. K.; Sangeetha, P.; Vijayaragavan, R, Mol.
Catal. 2018, 460, 53-62.
2. Creasey, J. J.; Parlett, C. M.; Manayil, J. C.; Isaacs, M. A.; Wilson, K.; Lee, A. F, Green
Chem., 2015, 17, 2398-2405.
3. Sun, L.B.; Liu, X. Q.; Zhou, H. C, Chem. Soc. Rev., 2015, 44, 5092-5147.
211
P119: N-Heterocyclic Carbene Catalysed acylation of 2-oxindoles using aldehydes to form 3-
alkenyloxindoles by C-C bond formation
Karthick Muthuvel,Thirumanavelan Gandhi*
Department of chemistry, School of Advanced science,Vellore Institute of Technology, Vellore Tamil
Nadu-632014
N-Heterocyclic carbenes (NHCs) have emerged as a powerful class of organocatalysts that mediate a
variety of organic transformations1. The diverse reactivity of NHCs in organocatalysis is due to the
possibility of different modes of action. Carbon–carbon bond forming reactions of enolates and their
synthetic equivalents constitute the bedrock of organic synthesis. Herein we report the NHC catalysed
acylation of 2-oxindoles using aldehydes to form 3-alkenyloxindoles by C-C bond formation in
moderate to good yields under mild reaction conditions. The reaction likely proceeds via the
generation of Breslow intermediate2. It is a 100% atom-economic process.
References:
1. Menon, R. S; Biju, A. T; Nair, V. Beilstein J. Org. Chem. 2016, 12, 444.
2. Breslow, R. J. Am. Chem. Soc. 1958, 80, 3719.
212
P120: Multi-Component approach for synthesis of quinolinyl-1,4-dihydropyridines and in vitro
evaluation of anticancer activity against MCF7
Selvendran Suresh,a Biswarup Basu,
b Souvik Dos,
b Kamran Waidha
c Saravanakumar Rajendran
a*
aChemistry division, School of Advanced Sciences, Vellore Institute of Technology Chennai Campus,
Chennai-600 127, Tamilnadu, India.bChittaranjan National Cancer Institute, Chitranjan, S.P.
Mukherjee Rd,Kolkata-700026. cAmity Institute of Biotechnology, Amity University Uttar Pradesh, ,
Noida-201303,India
Quinolines and 1,4-dihydropyridines are common to bio-active molecules and many commercial
drugs.1 Here we present a highly efficient and chemo-selective process for the synthesis of
polysubstituted quinolinyl-1, 4-dihydropyridines using a one-pot multicomponent approach and
evaluated their anticancer activity against the breast cancer cell line, MCF 7 via MTT assay in vitro.
Tetrazolo [1,5-a]quinoline-4-carbaldehyde, 3-oxo-3-phenylpropanenitrile, and β-enamine were reacted
in the presence of trimethylamine to obtain highly functionalized quinolinyl-1,4-dihydropyridines. The
product formation was ascertained by various spectroscopic analysis. Molecular structure of one of
the quinolinyl-1, 4-dihydropyridine derivatives is confirmed by single crystal X-ray diffraction. Among
the compounds evaluated, SKS19 was the most cytotoxicity, IC50 = 7.87 µM. Molecular docking was
conducted to understand the mechanism of inhibition. The above study corroborate quinolinyl-1,4-
dihydropyridines as a valuable scaffold to develop anticancer drug.
Scheme 1: Synthesis of polysubstituted quinolinyl-1, 4-dihydropyridines.
References:
1) Isaivani, D.; Padmini, V.; Bhuvanesh, N. ACS Comb. Sci. 2016,18, 5, 236.
2) Sandip, V. B.; Manish, P. P. Ind. J. Chem., 2012, 51B, 1388.
213
P121: Thermal and chemical stability studies of „Cs‟ and „Sr‟ ions immobilized simulated
crystalline apatite ceramic wasteform
Ramya Ravikumar and Buvaneswari Gopal * Department of Chemistry, School of Advanced Sciences VIT, Vellore-632 014
High-level nuclear waste stream constitutes both short- and long-lived radionuclides. Among the
short-lived radionuclides, caesium (Cs) and strontium (Sr) are the most heat generating fission
products that is also highly mobile in aqueous media.1 Hence it is vital to contain them in a stable host
matrix (primary barrier system) in order to isolate from biosphere.2,3
Lacunar apatite compound
NaPb4(PO4)3 was examined for immobilization of „Cs‟ and „Sr‟ ions, based on which simulated
wasteform of the formula Na0.9Cs0.1Pb3Sr(PO4)3 was designed. The X-ray diffraction analysis reveals
that the obtained apatite is a single phasic and isostructural with host matrix [NaPb4(PO4)3]. The
wasteform shows improved thermal stability and exhibits anisotropic thermal expansion behavior with
no phase transformation or any kind of thermal distress in the temperature range studied (RT- 973K).
The calculated average thermal expansion co-efficient (αavg) is found to be 14.4 x 10-6
K-1
with
preferential crystallographic expansion along c-axis. The chemical durability of the wasteform was
studied by MCC-5 dynamic leach test. The results indicate incongruent leaching of ions and negligible
leaching of Cs+ ion, with LRCs =10
-6- 10
-8 g/m
2/d, LRNa= 10
-2 g/m
2/d, LRPb = 10
-4 - 10
-6 g/m
2/d, LRSr =10
-
3 -10
-4g/m
2/d and LRP =10
-2 -10
-3g/m
2/d.
References:
1. Forsberg, C. W. Nucl. Technol. 2017, 131 (2), 252–268.
2. Neumeier, S.; Arinicheva, Y.; Ji, Y.; Heuser, J. M.; Kowalski, P. M.; Kegler, P.; Schlenz, H.;
Bosbach, Di.; Deissmann, G. Radiochim. Acta 2017, 105 (11), 961–984.
3. Orlova, A. I.; Ojovan, M. I. Materials. 2019, 12 (16), 2638.
214
P122: Photocatalytic activity study of SnTiO3-g-C3N4 nanocomposites towards degradation of
toxic rhodamine B dye from polluted water
Vignesh A., Boya Palajonna Narasaiah and Badal Kumar Mandal*
Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore-
632014, Tamilnadu, India.
Nowadays synthesis of photocatalytic materials is becoming important due to severe water pollution
from wastewater discharge of textile and pigment industries. Remediation of toxic organic dyes from
polluted water is an essential task to clean up water for avoiding further damage of our environment.
Hence scientists are searching new materials for degradation of organic dyes from water. In this
regards researchers are synthesizing novel materials which are capable of degrading organic dyes
under irradiation of visible light. In this study we have synthesized graphitic carbon nitride
nanomaterials and its metal oxide nanocomposites for the degradation of rhodamine B (Rh-B) dyes
after irradiation of visible as well as UV light (1-4). After characterization of the synthesized
nanomaterials using different instrumental techniques we have checked the effects of pH,
photocatalyst dose and different metal oxide graphitic carbon nitride nanocomposites on degradation
efficiency of Rh-B dyes. In addition, we have compared the degradation efficiency of different
nanocomposites between visible and UV light exposure (Fig. 1).
Figure 1: Photodegradation of Rh-B by SnTiO3-g-C3N4 nanocomposites under UV and visible light
exposure
References:
1. Kumar, A., Kumar, A., Sharma, G., Al-Muhtaseb, A.H., Naushad, M., Ghfar, A.A., Stadler, F.J.,
Chemical Engineering Journal 2018, 334, 462–478.
2. Li, G., Nie, X., Gao, Y., An, T., Appl. Catalysis B: Environ. 2016, 180, 726–732.
3. Jo, W.-K., Natarajan, T.S., Journal of Colloid and Interface Science 2016, 482, 58–72.
4. Kumar, A., Kumar, A., Sharma, G., Al-Muhtaseb, A.H., Naushad, M., Ghfar, A.A., Stadler, F.J.,
Chemical Engineering Journal 2018, 334, 462–478.
215
P123 Sol-gel Combustion Synthesis of Merwinite and its Biomedical Applications
Subhashree Praharaj, Senthil Kumar Venkatraman, and Sasikumar Swamiappan
a Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore-
632014,
Tamil Nadu, India
The multidisciplinary attribute of biomaterials requires scientists to contrive and concoct the
material, engineers to design and fabricate the prosthesis, and physicians to swot the response of
natural tissues on artificial biomaterials implanted in the body. Globally, it has been appraised that
about 60% of artificial bone substitutes are mustered of bioceramics. Thus, much enthrallment has
been rafted towards the use of different bioceramics for bioactive fixation of artificial implants. Energy
efficient sol-gel combustion method has been adopted for the synthesis of merwinite. Citric acid was
employed as a fuel while nitric acid played dual role as catalyst and oxidizer during gelation and
combustion respectively. The obtained merwinite was characterized by XRD and FT-IR to confirm the
phase purity. SEM/EDAX analysis wasemployed to study the morphology and elemental composition
of the material. The bioactivity of merwinite was investigated by immersing the scaffold in SBF. The
surface after immersion reveals the presence of hydroxyapatite layer over the surface. The presence
of antibacterial activity was confirmed using the zone of inhibition occurred around the test samplein
the bacterial lawn culture. The mechanical strength was found to be in the range of cortical bone.
Keywords: Merwinite, Citricacid, Combustion, Bioactivity, Antibacterial activity and Mechanical
strength
216
P124 A Review on Synthesis of Sugar Derived Biomolecules and Its Applications in
Asymmetric Synthesis
M. Priyanka, I. Usha Naga Lakshmi, P. Sushma, A. Srivani, R. Jayachandra and
Sabbasani Rajashekar Reddy*
Synthesis of D-Glucose, D-Ribose, D-Xylose, D-Galactose derived chiral ionic liquids by simple
approaches are described, which are characterised by NMR, ESI-MS. Carbohydrate based CIL‟s are
chemically stable and have used as reusable solvents and chiral catalysts for asymmetric Michael
addition reactions. Developed CCIL‟s were successfully employed in asymmetric Michael addition
reactions to produce Michael adducts in high yield with moderate enantio-selectivity. Further the
CCILs explored for the chiral discrimination of racemic Mosher‟s Acid.
Key words: Carbohydrates, Natural resources, Chiral Ionic Liquids, Asymmetric synthesis
Scheme 1: Recent work from our laboratory using natural carbohydrates
References: 1. (a). R.Jayachandra and S. R, Reddy, Trends in Carbo. Res. 2015, 7, 60. (b). R.Jayachandra, R. Lakshmipathy and S. R, Reddy. J. Mol. Liquids 2016, 219, 1172. (c). R. Jayachandra and S. Rajasekhara Reddy* Balakrishna. Chemistry Select. 2016, 1, 2341-2343. (d).. R. Jayachandra and S. R, ReddyR. Sc Advances. 2016, 6, 39758. (e). R. Jayachandra , S. R, Reddy, and R. Lakshmipathy. Environmental Progress & Sustainable Energy. 2019, S1-S450.
217
P125 An Overview on Regioselective Cascade Approaches for the Synthesis of 6H-Benzochromene, 6H-Benzochrome-6-ones and its Scope
Pooja Garg, B.Muralidhar, Gracevictoria Govada, I. Usha Naga Lakshmi, and Sabbasani Rajasekhara
Reddy*
.
Department of Chemistry, School of Advanced Science.
Vellore Institute of Technology, Vellore..
Polycyclic heterocycles with annulations of benzochromene framework are widely distributed in the
nature and have great biological and pharmacological significance. Numerous natural products in
which benzene ring is fused angularly or linearly to a chromene ring system have been isolated,
synthesized, and characterized by various spectroscopy techniques and single crystal X-ray
diffraction analysis. Depending upon the fusion of benzene ring to different sites of chromene ring,
various benzochromene systems such as benzo[c]-, benzo[f]-, benzo-[g]-, and benzo[h]chromenes
are reported. Present work will describe the various synthetic strategies to construct the 6H-
Benzo[C]chromene and 6-H Benzo[C]chromenone analogues and its scope.
Scheme.1:Synthesis of 6H-benzo[C]chromene and 6H-benzo[C]chromenone.
References:
[1] (a) Villuri, B.K.; Ichake, S.S.; Reddy, S.R.; Kavala, V.; Bandi, V.; Kuoand, C-W.; Yao, C-F.; J. Org. Chem.2018, 17, 10241. (b) Bandi, V.; Kavala, V.; Konala, A.; Hsu, C-H.; Villuri, B. K.; Reddy, S. R.; Lin, L.; Kuo, C-W.; Yao, C-F. J. Org. Chem.2019, 84, 3036. (c) Sachin, S. I.; Kumar, V. B.; Reddy, S. R.; Kavala,V.; Yao, C-F. Org. Lett.2019, 21, 2256. [2] (a) Muralidhar, B. and Reddy, S R Bull. Chem. Soc. Jpn.,2018, 91, 65.(b) Naidu, S.; and Reddy, S..R. RSC Advances.2016, 6, 62742.(c) Reddy, C. B. R.; Reddy, S.R.; Naidu, S. Catal. Commu.2014, 56, 50. [3] (a)Ramendra, P.; Vishnu Ji, R.Chem Rev. 2004, 114, 10476 (b) Iaroshenko, V.O.;
Abbasi, M.S.A.; Villiger, A.; Langer, P. Tetrahedron Lett.2011, 52, 5910. (c) Bhattacharya,
P.; Senapati, K.; Chattopadhyay, K.; Mandal, S.M.; Basak, A. RSC Advances2015, 5, 61562.
218
P126 Overview on Synthesis of Sugar Based Ionic Liquids for Sustainable Societal
Applications
P. Krishnaraj, M.Priyaunka, R. Jayachandra and Sabbasani Rajashekar Reddy*
School of Advanced Sciences, Department of Chemistry, VIT University, Vellore-632014, India.
Sugars are the most abundant bio-organic molecules. Exploring these molecules into value
added applications are most important area of research work due its nontoxic in nature wide
availability. Applications of sugar derived ionic liquids were never been explored purification of water.
However, carbohydrate based chiral auxiliaries, chiral catalysts and reagents have shown excellent
applications towards asymmetric synthesis. Of late, our group reported the syntheses of sugar
derived ionic liquids by simple synthetic approaches. Which are characterised by various analytical
techniques. Of late, removal of toxic metals ion like Pd+2,
Cd+2
etc., from the aqueous solutions is
important area of research work. In this presentation, we are planned the overview the synthesis of
sugar based ionic liquids and its applications in removal of toxic metals such as like Pd+2,
Cd+2
etc.,
from aqueous solution.
Key words: Carbohydrates, Synthesis, Sequestration and toxic metals
Scheme 1: Recent work from our laboratory using natural carbohydrates
References:
1. (a). R.Jayachandra and S. R, Reddy, Trends in Carbo. Res. 2015, 7, 60. (b). R.Jayachandra, R.
Lakshmipathy and S. R, Reddy. J. Mol. Liquids 2016, 219, 1172. (c). R. Jayachandra and S.
Rajasekhara Reddy* Balakrishna. Chemistry Select. 2016, 1, 2341-2343. (d).. R. Jayachandra and S.
R, ReddyR. Sc Advances. 2016, 6, 39758. (e). R. Jayachandra , S. R, Reddy, and R. Lakshmipathy.
Environmental Progress & Sustainable Energy. 2019, S1-S450.
219
P127 Benzo [4, 5] thiazolo [3, 2-a] pyrimidine-3-carboxylate based Colorimetric Sensor for the
Detection of Fe3+ and Cr3+ ions
Shanthi Seenan and Kulathu Iyer Sathiyanarayanan* Department of Chemistry, School of
Advanced Sciences, Vellore Institute of Technology, Vellore-632014
ABSTRACT
Benzo [4, 5] thiazolo [3, 2-a] pyrimidine-3-carboxylate (4a) was synthesized. The changes in
absorption properties of compound 4a in the presence of various cations were evaluated.
Compound 4a can acted as colorimetric sensor for highly sensitive and selective detection of
Fe3+
and Cr3+
in acetonitrile solvent. Using measurements of absorbance intensity, the
binding constant for 4a+Fe3+
complex and 4a+ Cr3+
complex was found to be 1.958×108 M
-1
and with the lower detection limit of 52 nM and 112 nM respectively.1H NMR titration,FT-
IR, ESI-Mass spectrum, and Job's plot were taken to confirm the mechanism of the specific
reaction and colorimetric sensing of 4a+Fe3+
and 4a+Cr3+
.The application of compound 4a
for the determination of Fe3+
in spiked samples of iron tablet in changed environmental water
samples showed a satisfactory result with good recovery.
References:
1.Sahu, P. K.; Sahu, P. K.; Agarwal, D. D. Efficient and Facile Synthesis of Heterocycles and Their
Mechanistic Consideration Using Kaolin. RSC Adv.2013, 3, 9854–9864.
2. Tripathi, M.; Reddy, P.; Rawat, D. Chemistry & Biology Interface. Chem. Biol.2014, 4, 1–22.
3. Qu, Q.; Wang, F.; Zhao, Q.; Chen, X.; Zou, W. A Colorimetric Fe3+
Sensor Based on an Anionic
Poly (3, 4-Propylenedioxythiophene) Derivative. Sensors Actuators B Chem.2017, 244, 891–896.
4.Arockiam, J. B.; Ayyanar, S. Benzothiazole, Pyridine Functionalized Triphenylamine Based
Fluorophore for Solid State Fluorescence Switching, Fe3+
and Picric Acid Sensing. Sensors and
Actuators, B: Chemical.2017, 242, 535–544.
220
P128 Rational synthesis of tetrahydrodibenzophenanthridine and phenanthroimidazole as
efficient blue emitters and its applications
ManojkumarDhanthalaThiyagarajana, UmamaheshBalijapalli
a, b, SohrabNasiri
c, DmytroVolyniuk
c,
JurateSimokaitienecc, SathiyanarayananKulathuIyer
*a, JuozasVidasGražulevi ius
*c and
Prof.Madhvesh Pathak*a
Department of Chemistry
SAS, Vellore Institute of Technology, Vellore-632014.
Ten luminophores based on tetrahydrodibenzophenanthridine (THDP) and phenanthroimidazole (PI) were designed, synthesized and characterized for their thermal, electrochemical, electro-optical, charge-transporting characteristics and electroluminescent properties. The blue luminophores exhibited high photoluminescence quantum yields of 66-93% in toluene solutions and of 5-59% in solid films. The highest values were observed for the derivative of THDP and PI containing methoxy group. The compounds showed close values of ionization potentials (5.74-6.11 eV) and electron affinities (2.71-3.06 eV). The selected compounds were tested in electroluminescent devices for the preparation of non-doped light-emitting layers. The best device fabricated using derivative of THDP and PI with methoxy groups showed blue electroluminescence with brightness of 10000 cd/m
2 at high
applied voltages. We performed DFT calculations, and observed lowest singlet-triplet gap (∆EST) values of 0.33 and 0.03 eV, oscillator strength (f) values of 0.034 and 0.008 for CN and NO2 derivatives. Interestingly, we observed that compounds 3g and 3i showed HOMO and LUMO levels of almost similar energy gap (Eg) of 3.60 eV and we observed deeper HOMO values of -5.30, -5.33 eV and LUMO values of -1.94, -2.77 eV.
Graphical abstract
References:
1. G. M. Farinola, R. Ragni, Chemical Society Reviews.2011, 40, 3467-3482.
2. H. Ulla, B. Garudachari, M. N. Satyanarayan, G. Umesh, A. M. Isloor, Optical Materials.2014, 36,
704-711
3. M. A. Baldo, M. E. Thompson, S. R. Forrest, Nature.2000, 403, 750-753
4. J. Tagare, S. Vaidyanathan, Journal of Materials Chemistry C.2018, 6, 10138-10173.
221
P129 Ni(II) Assisted Catalytic Transfer Hydrogenation Reactions of Carbonyl Compounds
Rakesh R Panicker, Sadhana Venkatesh, Chayan Pandya and Akella Sivaramakrishna*
Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology,
Vellore – 63 2014, Tamil Nadu, India.
The catalytic transfer hydrogenation reactions of a series of aromatic and aliphatic carbonyl
compounds were investigated using divalent Ni(II)-diphosphine complexes of the type [L2NiCl2]
(where L2 = 1,1-bis(diphenylphosphino)methane (dppm), 1,2-bis(diphenylphosphino)ethane (dppe),
1,3-bis(diphenylphosphino)propane (dppp) and 1,1-bis(diphenylphosphino)ferrocene (dppf)). This is a
single-step reaction in the presence of potassium hydroxide and isopropyl alcohol to give
corresponding alcohols. This protocol tolerates other sensitive functional group like olefinic double
bonds, but also achieves high chemoselectivity. All the reactions were monitored by GC and GC-MS.
The plausible mechanism was also discussed. The method reported in the present paper is simple,
cost-effective and provides excellent conversions. Nickel-diphosphine complexes appear as a
potential alternative to the expensive transition metal complexes.
Key words: Nickel(II)-diphosphine complex, catalytic transfer hydrogenation, carbonyl compounds,
alcohols.
222
P130 New Phosphine Oxide based Cerium (IV) Complexes: Synthesis, Structural
Characterization and their Coordination Behaviour
Vijai Anand A S, and Akella Sivaramakrishna* Department of Chemistry
Vellore Institute of Technology, Vellore, Tamilnadu, India. Pincode- 632014
The availability of a range of various lanthanoid metals, coupled with a large amount of different
ligands, provides an effective way to systematically fine-tune the properties of the coordination
complexes of lanthanides1.This helps to control their catalytic behaviour efficiently, such as
chemoselectivity, enantioselectivity and diasterioselectivity. Reactions involving organolanthanoid
catalysts involve mild inert reaction conditions. Hydrocarbon solvents are generally used for catalytic
reactions as they are able to bind to the Lanthanide center. The presence of bulkier R groups can
significantly affect the catalytic activity due to the steric demands of the ligands, which can hinder the
association of the lanthanoid with the desired organic substrate, but also allows specificity to be built
into the catalyst. The present work is mainly focused on synthesis of selected new cerium complexes
using phosphine oxides as binders. But the literature on chemistry and applications of these
complexes is very limited 2. The prepared cerium complexes were characterized by spectroscopic and
analytical techniques. The coordination behaviour of these complexes with respect to solvent, nature
of ligand, temperature and ligand crossover is investigated.
Keywords: Cerium, Phosphine Oxide, Coordination behaviour, Organic reactions.
References:
1. Housecroft, C.E.; Sharp, A.G. J. Chem. Educ. (2003),80, 7, 747
2. Nair, V.; Balagopal, L.; Rajan, R.; Mathew, J. Acc. Chem. Res. (2004), 37(1), 21-30. and
Coles, S. J.; Fieldhouse, S. J.; Klooster, W. T.; Platt, A. W. Polyhedron. (2019), 161, 346-351.
223
P131 Photocatalytic Remediation of Environmentally Toxic Dyes by ZnTiO3/g-C3N4
Nanocomposites
Sim Simon., Boya Palajonnala Narasaiah and Badal Kumar Mandal*
Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore-
632014, Tamilnadu, India.
The dyes are hazardous to the environment. Even 1 mg/L of dye can cause serious problems
to environments [1]. Dye concentration higher than 1mg/L caused by the direct discharge of
textile effluents can give rise to contamination of water and soil which causes severe
problems to ecosystem [2]. Hence, it is necessary to develop remediation methods through
successive cheaper possible routes for making this toxic form of dyes or dye effluents to non-
toxic form like mineral acids and H2O [3]. So, in this work we mainly focused on synthesis of
ZnO, TiO2, ZnTiO2, g-C3N4, ZnO-g-C3N4, TiO2-g-C3N4 and ZnTiO2-g-C3N4 through a
chemical route for dye degradation. Nanocomposites were characterized using XRD, UV-
DRS, UV-Visible spectroscopy. The synthesized different nanocomposites were checked for
the degradation of direct methylene blue under UV and Visible light using Heber photo
reactor. Degradation of dyes was monitored periodically using UV-Visible spectroscopy.
Results indicate that the synthesized nanocomposites exhibited higher degradation efficiency
to MB dye under UV-irradiation within shorter time compared to visible light exposure. The
results of this study suggest that the synthesized nanocomposites could be promising
materials for photocatalytic degradation of dyes or environmental remediation.
Figure 1: Photodegradation of MB by ZnTiO3-g-C3N4 nanocomposites under UV and visible
light exposure
References:
1. Li Li, Shu-Qing Sun, Yong-Xing Wang, Chuan-Yi Wang, Journal of Photochemistry and
Photobiology A: Chemistry 2018, 355, 16-24.
2. Eunyong Jang, Dae Woong Kim, Seong Hwan Hong, Young Min Park, Tae Joo Park, Applied
Surface Science 2019, 487, 206–210.
3. Masoud Salavati-Niasari, Faezeh Soofivand, Ali Sobhani-Nasab, Maryam Shakouri-Arani,
AliYeganeh Faal, Samira Bagheri, Advanced Powder Technology 2016, 27, 2066-2075.
224
P132 Synergistic effect of cinnamon-chitosan Schiff base in wastewater treatment
Thandapani Gomathi*, E. Swetha and P.N. Sudha
PG and Research Department of Chemistry,
D.K.M. College for Women, Vellore, Tamil Nadu, India
The aim of this study was to evaluate the synergistic effect cinnamon and chitosan on the
removal of methylene blue dye and chromium from aqueous solution. Ethanol extract of cinnamon
bark was mixed with chitosan solution to prepare Cinnamon-chitosan Schiff base (ECCSB) and
analyzed using FTIR and XRD for its formation and suitability for wastewater treatment. FTIR results
confirmed the formation of Schiff base by showing band at 1647 cm-1
. XRD analysis showed that the
prepared cinnamon-chitosan Schiff base was amorphous in nature with the degree of crystalinity 9%.
The porosity measured via liquid displacement method showed the porosity of 88.86% and the
prepared Chitosan cinnamon Schiff Base showed good antioxidant and antimicrobial activity. In vitro
biodegradation assay revealed that the time increases the percentage of degradation also increases.
Batch adsorption study was carried out for the removal of methylene blue dye and chromium metal
ion by varying the parameters such as pH, adsorbent dose, contact time and initial concentration. The
experimental data were analyzed by the Langmuir and Freundlich isotherm models, the results were
well fitted to the Frundlich isotherm model. The kinetics experimental data properly correlated with the
pseudo second order kinetic model than the pseudo first order kinetics. The results indicate that
ECCSB could be employed as the promising material for wastewater treatment even at low
concentration.
Keywords: Cinnanon, Chitosan Schiff base, Methylene blue, Batch adsorption study
References:
1. Hossein, N.; Zahra, Z.; Abolfazl, M.; Mahdi, S.; Ali, K. Journal of Medicinal Plants Research,
2013, 7, 1339–1343.
2. Ismat, H.; Ali Mohammed, K.; Al Mesfer Mohammad I.; Khan, Mohd Danish; Majed, M.
Alghamdi, Processes 2019, 7(4), 217.
225
P133. Synthesis, Characterisation and Sorption studies for the removal of Cr (VI) using doubly
grafted Chitosan oligosaccharide blend (COS – g – MAH - g – AA / PPG)
G. Kotteeswari and P. N. Sudha*
PG and Research Department of Chemistry,
D. K. M College for Women, Vellore, Tamilnadu, India
Chitosan oligosaccharide biopolymer has outstanding advantages over chitin and chitosan. It is water
soluble, non-toxic, biocompatible and offer possibilities of chemical modifications for various
applications. In this present study chitosan oligosaccharide is modified as chitosan oligosaccharide –
g – maleic anhydride – g – acryl amide / poly propylene glycol blend. The prepared blend was
analysed using FTIR, XRD, TGA, DSC and SEM analysis. Batch adsorption studies were carried out
to find the adsorption efficiency of the material prepared by varying the parameters such as adsorbent
dose, contact time, pH and initial concentration of the metal solution. The results are fitted with
Langmuir and Freundlich isotherm models. Desorption studies were done by varying contact time.
Key words: Chitosan oligosaccharide, maleic anhydride, acrylamide, poly propylene glycol,
blending, adsorption, desorption, Langmuir and Freundlich isotherms.
References
1. Vilela, P.B.; Dalalibera, A.; Duminelli, E.C.; Becegato, V.A.; Paulino, A.T. Environ Sci Pollut
Res Int. 2019, 26(28), 28481-28489.
2. Vusumzi, E.P.; Nikita, T.T.; Lawrence, M.M. RSC Advances, 2019, 45.
226
P134 Enhancing cell penetration and proliferation in Nanochitosan /Silk Fibroin binary
Scaffolds Using MC3T3-E1 Cell Line for tissue engineering applications
S. Gokila, T. Gomathi, Anil Sukumaran and P.N. Sudha*
Biomaterials Research Lab, Department of Chemistry, D.K.M. College for Women, Vellore,
TamilNadu, India.
NanoChitosan /Silk-Fibroin of binary scaffold was prepared and chemically crosslinked were geared
up by the simple ionic cross linking method using TPP to get better bioavailability . Thermal and
morphological studies were performed for the prepared binary scaffolds. Characterizations of the
binary scaffold were investigated by thermo gravimetric analysis (TGA), differential calorimetry
(DSC). TGA and DSC studies reveal that the thermal stability of the blend is enhanced to carry out
biomedical applications. In-vitro cell culture study using MC3T3-E1 cells has shown an enhanced
cell attachment, proliferation and differentiation. An enhanced scaffold porosity, hydrophilicity, cell
adhesion and cell proliferation were further achieved by the incorporation of the binary Scaffolds
NCS/SF. Some of the assays studied in the cell line- MC3T3-E1 include, ALP and Fluorescent Assay.
Antimicrobial studies were also done and sample has the potential to kill the microorganisms to a
greater extent. In addition to biocompatibility and satisfactory cell affinity, this material will have great
potential applications in the field of bone tissue engineering. In the near future, it is most likely that
the NCS/SF scaffold based systems would help to reconcile the clinical and commercial demands in
tissue engineering.
Keywords: silk fibroin, Nanochitosan, biomaterial, scaffolds, cell culture, in vitro studies.
References
Sangeethaa, V; Sudha, P.N; gomathi, T ; jayaprabakar, J, Journal of Nanomaterials and
Biostructures. 2019, 14, 963-972.
227
P135 Removal of Toxic Heavy Metal Chromium Using
Nanochitosan/Carboxymethylcellulose/Graphene Oxide Nano Composite
S. Sugashini and P.N. Sudha*
Biomaterials Research Lab, Department of Chemistry, DKM College for Women (Autonomous),
Vellore, India
The removal of heavy metals from wastewater is essential to avoid pollution. In the present
work ternary Nanochitosan(NC)/Carboxymethyl cellulose (CMC)/ Graphene Oxide(GO)
nanocomposite was used under different experimental conditions for the removal of Chromium from
water. Advanced analytical techniques such as FT-IR, XRD, TGA and DSC were used to study the
physicochemical properties of the composite. The Batch adsorption studies were conducted using the
prepared ternary nanocomposite by varying the parameters such as pH, adsorbent dosage, contact
time and initial Cr(VI) ion concentration. The adsorption data has been used to explain the kinetic
model, Langmuir and Freundlich isotherm equations. From the results it is proved that NC/CMC/GO
nanocomposite was formed and can be used as a promising material for treating industrial effluents.
Keywords: Nanochitosan, Carboxymethyl cellulose, Graphene oxide, Nanocomposite chromium (VI)
adsorption.
Reference:
1. Leonard, A,; Lauwerys, R.R, Mutat. Res. 1980, 76,227-239.
2. Langard, S. Biological and environmental Aspects of Chromium. McGraw Hill Book Co., Inc, New
York. 1893, 314.
228
P136. Removal of Cr (VI) from Aqueous Solution using Orange Peel-based Biosorbents
S. Pavithra and P.N. Sudha*
Biomaterials Research Lab, Department of Chemistry, DKM College for Women (Autonomous),
Vellore, India.
Now-a-days, adsorption has been recognized as an effective method to remove heavy metals ions in
water sources. Chromium is a considerable environmental concern as it is widely used in leather
tanning, electroplating, metal finishing and chromate preparation. Chromium occurs in aqueous
environment in trivalent and hexavalent forms. Hexavalent chromium is more toxic than the trivalent
form because of its carcinogenic and mutagenic effects. During the last decade, hydrogels have been
used as potential adsorbents for removal of contaminants from aqueous solution. A novel hydrogel
based on the orange peel (OP) and chitosan was prepared by solgel method. This work is focused
on studying removal of chromium (VI) from aqueous solution by orange peel-based adsorbents (OP,
OP-Chitosan). Effects of pH and adsorbent dosage on the adsorption of Cr (VI) were evaluated in
order to determine suitable conditions for carrying out adsorption process. The prepared hydrogel was
characterized using various analytical techniques such as FT-IR, XRD, Thermal studies (TGA and
DSC) studies. The swelling behaviour was determined as a function of swelling time. The developed
hydrogel was used for the removal of Cr6+
from synthetic water.
Keywords: Adsorption, Biosorbent, Chromium, Orange peel, Chitosan.
References
1. Tejada-Tovar, C; Gonzalez-Delgado, A.D; and Villabona-Ortiz, A, Indian Journal of Science
and Technology 2018, 11(13).
2. Jisha, T.J; Lubna, C.H; Habeeba, V; IJARIIE 2017, 3(4).
229
P137 Synthesis, characterization and biomedical applications of chitosan and carboxymethyl
chitosan – salicylaldehyde cobalt complexes
C. Mujeebur Rahman and M. S. Dastageer*
Department of Chemistry,
C. Abdul Hakeem College, Melvisharam, Vellore, Tamil Nadu, India
The present study was aimed to carry out by synthesizing new chitosan and carboxymethyl chitosan
Schiff bases using salicylaldehyde to investigate their efficiency and to study their activity for
biomedical application. These Schiff bases are then complexed with the transition metals such as
cobalt and these novel derivatives were characterized to analyse their formation, thermal stability and
its physical state, through FTIR, TGA, DSC and XRD. FTIR spectral analysis showed characteristic
bands confirming the Schiff base formation and its metal complexes which are coordinated to the
Schiff base ligands. The characteristic peaks in the range of 1600 - 1680 cm-1
confirms the presence
of the C=N imine linkage and aromatic C=C group. The thermogram results revealed that there was a
change in thermal behaviour in all the Schiff base polymers and their complexes. From the XRD
investigations it could be found out that the derivatives showed poor crystallinity. In vitro antimicrobial
studies and cytotoxicity studies were carried out for the prepared derivatives to study its suitability for
biomedical applications. The results revealed that the materials had an appropriate surface for the
sequential responses, which are essential for cell survival and function.
Keywords: Schiff base complexes, Chitosan, Carboxymethyl chitosan, Biomedical application
References:
1. Joydeep Dutta; Pradip Kumar Dutta. In Chitin, Citosan, Ologosaccharides and their Derivatives.
Biological Applications. Ed. Se-Kwon Kim. CRC Press. 2010, 195-214.
2. Keegan, G.M.; Learmonth, I.D.; Case, C. Crit. Revs. Toxicology. 2008, 38, 645-674.
230
P 138. Wound healing applications of biosilica/silk fibrion/polyurethane foam blend
P. Supriya Prasad and M. Deepa*
Department of Chemistry,
Muthurangam Government Arts College, Vellore, Tamil Nadu, India
(*Corresponding author: Email:
Biosilica based material have a good application in the biomedical field, especially in would healing
application. Microbial contamination in wounds leading to severe sepsis can be treated with
antiseptics and frequent treatment with antiseptics leads to staining of skin, burning, and irritation at
the application site. Thus, the present was aimed to formulate biosilica/silk fibrion/polyurethane foam
blend with antimicrobial properties for accelerated wound healing. The prepared wound dressing
material was characterized using Fourier transform infrared spectroscopy for its formation. The
suitability of the material was evaluated by antimicrobial studies and the results revealed that
biosilica/silk fibrion/polyurethane foam blend have higher bactericidal activity. The in vivo animal tests
were employed to confirm the biocompatibility of the blend as wound-dressing application. An in vivo
model revealed that biosilica/silk fibrion/polyurethane foam blend had superior wound closure as
supported by results of histopathology. Based on the results, biosilica/silk fibrion/polyurethane foam
blend will become a promising biomaterial for wound dressing application.
Keywords: Biosilica, polyurethane foam, wound healing application
References:
1. Yuvarani, I.; Sunil Jai Kumar; Jayachandran Venkatesan; Se-kwon Kim; Sudha, P.N.
Materials Science, 2012, 10.1166/jbt.2012.1037
231
P139. Bactericidal effect of Murraya Koenigii sparg leaf extract modified CaO nanoparticles
S. Ananda, P. N. Sudha
b, R. Arunadevi*
b,
aEntomology Research Institute, Loyola College, Chennai-600034, Tamil Nadu, India.
bDepartment of Chemistry, D. K. M. College for Women (Autonomous), Vellore-632001, Tamilnadu,
India.
With an increase in antibiotic resistance, a growing interest in developing new antimicrobial agents
has gained popularity. Metal-and metal-oxide-based nanoparticles, surface-to-volume is able to
distinguish bacterial cells from mammalian cells and can provide long-term antibacterial activity. CaO
nanoparticles were synthesized using Murraya Koenigii sparg leaf extract by biogenic method. The
products were characterized by Scanning electron microscope (SEM), Ultra violet visible diffuse
reflectance spectra (UV-vis-DRS), energy dispersive X-ray spectroscopy (EDX), photoluminescence
spectroscopy (PL) and x-ray diffraction (XRD) techniques. The band gap were observed to be 5.67
and 5.3 eV, CaO and Murraya Koenigii sparg (MKCA) leaf extract modified CaO respectively. The
results of SEM revealed that development of MKCA nanoparticles have flake with plate like
morphology. We used these nanomaterials to evaluate their antibacterial activity against both Gram-
negative and Gram-positive bacteria.
Figure: SEM image of MKCA
References:
1. Arunadevi, R.; Kavitha, B.; Rajarajan, M.; Suganthi, A.; Jeyamurugan, A.; Surfaces and
Interfaces, 2018, 10, 32–44.
2. Gajjar, P.; Pettee, B.; Britt, DW.; Huang, W.; Johnson, WP.; Anderson, AJ.; J Biol Eng. 2009,
3 (9), 1-13.
232
P140 Chemical modification of Chitosan Oligosaccharide derivatives for the Removal of
Cadmium(II) ions from aqueous solution.
E.Radha and P.N.Sudha*
Biomaterial Research lab, PG & Research Department of Chemistry,
D.K.M. College for Women, Vellore, Tamilnadu, India
To develop low-cost and environmentally responsive polymeric materials for enrichment,
remediation of metal ions from aqueous solution, novel reactive graft copolymers based on Chitosan
Oligosaccharide were synthesized by grafting and blending process. Structural aspects of graft
copolymers have been characterized by FTIR, XRD, TGA and SEM analysis. The sorption capacity
was brought under batch mode to suit the optimal parameter viz., initial concentration, adsorbent
dose, pH, and agitation time which influences the sorption. Experimental data were analyzed by
Langmuir, Freundlich and Temkin adsorption isotherms. The isotherm study revealed that the
equilibrium adsorption is well-fitted to the Freundlich isotherm. The adsorbed sample was
characterized by SEM –EDAX and FTIR analysis, which confirmed that interaction between adsorbate
and adsorbent took place effectively. The metal loaded sorbent was taken for desorption studies. The
desorption kinetic studies showed that the desorption process follows pseudo second order kinetics.
Keywords: Chitosan oligosaccharide(COS), Grafting, Blending, Adsorption, Desorption
References
1 Sun, T; Hu, D.M; Xie, J, Natural Product Research and Development, 2012, 164-167, 190.
2 Prakash, N; Sudha, P.N; Renganathan, N.G, 2012, Environ. Sci.Pollut. Res. 19, 2930–2941.