undergraduate student chemistry conference...2018/04/13 · welcome message from dr. ian hamilton,...

46th Southern Ontario

Undergraduate Student

Chemistry Conference

March 24th, 2018

Hosted by the Department of Chemistry and

Biochemistry

#SOUSCC2018

Campus

Map#SOUSCC2018

Welcome Message from Dr. Ian Hamilton, Department Chair, Chemistry and Biochemistry

On behalf of the Department of Chemistry and Biochemistry, I am delighted to welcome you to the 46th Southern Ontario Undergraduate Student Chemistry Conference at Wilfrid Laurier University, Waterloo, Ontario. We hope that while you’re here you have the opportunity to talk with our faculty and students about our research facilities and graduate programs.

The SOUSCC 2018 program includes 103 oral presentations and 33 poster presentations for a total of 136 presentations from excellent undergraduate students in universities across southern Ontario. We are also pleased to welcome Dr. Cathleen Crudden, from Queen’s University, as our plenary speaker.

This conference would not be possible without our sponsors and volunteers, so we thank them greatly. The majority of our volunteers are undergraduate students dedicated to their studies and we appreciate their time commitment. These students were coordinated by our Laurier Chemistry Association (LCA), current holders of the Canadian Society for Chemistry (CSC) Student Chapter Merit Award.

We hope that SOUSCC46 serves as an inspiration to you, the next generation of chemists and biochemists, and allows you to share and celebrate your research with your peers, colleagues, and friends.

Yours sincerely,

Ian Hamilton, Professor and Chair Department of Chemistry and Biochemistry Wilfrid Laurier University

Cathleen Crudden (Queen's University)

Cathleen Crudden is full Professor and Canada Research Chair (Tier 1) atQueen’s University. She also holds a cross appointment as a ResearchProfessor at the Institute of Transformative Bio-Molecules (ITbM) in NagoyaJapan. She is one of only four international faculty at ITbM, where she runs asatellite lab funded by the Japanese government. She has won numerousresearch awards including the 2018 Canadian Catalysis Society Award, the2017 R. U. Lemieux award and the 2011 Clara Benson award. She is a fellowof the Chemical Institute of Canada (2014) and the Royal Society ofChemistry (UK, 2017). She was a Killam Research Fellow from 2015-2016.Cathleen has been a visiting professor in the labs of Professor Ryoji Noyori,was awarded a Global Center of Excellence Professorship at Kyoto Universityand a Visiting Professorship in Tarragona, Spain.

Cathleen was one of the first grantees of the CREATE program ($1.6M,2010-2016) and is PI on a successful 2014 CFI grant for $8.8M in the area ofsurface science. She is also one of two Canadians that are part of a Japan–Germany–Canada trilateral research partnership.

Cathleen was President of the Canadian Society for Chemistry in2012/2013 and served on the Board of Directors for two terms representingthe Catalysis Division. She also served on the Editorial Advisory Board forACCN for ten years, and has been one of two Canadian members of theorganizing committee of Pacifichem for the past 10 years. She is chair of theNSERC–Chemistry Liaison Panel.

Cathleen is Associate Editor for ACS Catalysis and sits on the editorial advisory boards of Chemical Record (Japan), Synthesis, Organometallics, ACSOmega and Chemical and Engineering News. Her work in catalysis and materials has received significant acclaim, with recent work identifying a new class of carbon-based SAMs being called "game changing" and "the new gold standard" by international experts in the area.

Dr. Cathleen

Crudden#SOUSCC2018Plenary Speaker

Organizing Committee Members for SOUSCC46

Steve MacNeil Lillian DeBruin Louise Dawe Ken Maly Lana Hiscock

Zahra Yussuf

A warm thank you to our judges. Your expertise and generosity with your time is sincerely appreciated.

Thank You!

#SOUSCC2018

This Photo by Unknown Author is licensed under CC BY-SA

http://2008chemistry11.wikispaces.com/Emil+Erlenmeyer

https://creativecommons.org/licenses/by-sa/3.0/

THANK

YOU

TO OUR SPONSORS

Canadian Association of

Theoretical Chemists

Pearson Education Canada

Chemical Institute of

Canada

Chemical Education Fund

Divisions: Biological and Medicinal

Chemistry, Analytical, Chemistry

Education, Environment, Inorganic,

Organic, Physical, Theoretical and

Computational, Materials Chemistry

Local Sections: Peterborough and

Toronto

Wiley

Wilfrid Laurier University

Department of Chemistry and Biochemistry, Faculty of

Science Students’ Association, Faculty of Science,

Office of the Vice-President: Academic, Teaching and

Learning, Office of Research Services

CEM Corporation

Mirexus Inc.

University of Windsor

Department of Chemistry

and Biochemistry

#SOUSCC2018

THANK

YOU TO OUR VOLUNTEERS

Sincerest thanks to all the volunteers who have helped run SOUSCC

2018 at Wilfrid Laurier University. Your contributions before and

during the conference were greatly appreciated. A special thank you

goes out to Emrys for designing our volunteer shirts and the

members of the Laurier Chemistry Association for planning the

social events and organizing a photo booth for the banquet. Thank

you all so much for your hard work, commitment, and effort. This

conference would not have been possible without the help of each

and every one of you.

"Alone we can do so little; together we can do so much.”Helen Keller

Tala Aduadas Kwasi Adjei

Hira Ahmad

Kissa Batul Breanna Chapman Ruhana Chowhan

Robert Clarke Rachel Dickie

Patryk Dorozynski Heather Gaebler Shaeley Gibbons Chenique Gilroy

Emrys Halbertsma Timothy Ho

Neil Jurkiewicz Hailey Keeler Zoe Mowbray

Brittany Nagy

Rahma Noushin

Amanda Pang

Kevin Pattison

Ummesalama Potia

Alena Pratasouskaya

Nicole Ritter

Kayla Samms

Fredrick Sato

Edward Schmidt

Elizabeth Silva

Misha Singh

Dana Sowa

James Stevenson

Mayuran Sweentherarajah

Amisha Yadav

#SOUSCC2018

Program at a Glance

8:15-9:15am

Registration &

Coffee Bricker Academic (BA) Foyer

Poster Set-up Paul Martin Center (PMC)

9:15-9:30am Opening Remarks BA201

9:30-10:20am Keynote lecture

10:30-12:10pm

Session 1

BA110 BA111 BA112 BA208 BA209 BA210 BA211

IN/M

1

IN/M

2 OR 1 PCT 1 AN 1 B/M 1 GEN

12:10-

12:40pm Lunch Senate & Board Chamber

12:40-1:40pm Poster Session Paul Martin Center (PMC)

1:40-3:20pm Session2

BA110 BA111 BA112 BA208 BA209 BA210 BA211

IN/M 3

IN/M 4

OR 2 PCT 2 AN2 B/M 2 B/M 4

3:20-3:50pm Coffee Break

3:50-5:30pm Session 3

BA110 BA111 BA112 BA208 BA209 BA210 BA211

IN/M 5

IN/M 6

OR 3 PCT 3 PCT 4 B/M 3 B/M 5

5:40-6:00pmJudges' Meeting SR113

Poster Take-down Paul Martin Center (PMC)

6:00-9:00pm Banquet & Awards Turret

IN/M Inorganic & Materials OR Organic

B/M Biological & Medicinal AN Analytical

PCT

Physical; Comp;

Theoretical GEN General

#SOUSCC2018

Detailed Oral Presentation Schedule

Room

ID Name Title

10:30-10:50am 34 CruzDesigning Patchy Rod-Like Micelles: Manipulating

Competitive Seeded-Growth Kinetics and Visualizing

Patchiness by Selective Staining

10:50-11:10am 51 VentimigliaSynthesis of a Fluorogenic Substrate to Monitor Redox

activity in Cystathionine

11:10-11:30am 63 PlummerEffects of Metacognitive Practices on Introductory Organic

Chemistry Students. A Closer Look at Learning Task

Inventories

11:30-11:50am 83 Bani MS in probing protein-small molecule interaction

11:50-12:10pm 91 YousifSynthesis of small molecule biological antifreezes and

applications in cryopreservation

Room

ID Name Title

10:30-10:50am 21 AdjeiNickel & Palladium (N,O)-Donor Ligand Complexes:

Structure & Catalysis

10:50-11:10am 33 Yunyaeva Ionic Networks for Controlled Drug Delivery

11:10-11:30am 84 DengOptimized synthesis of pyridine-based porphyrins for

comparative homogeneous electrocatalytic reduction of CO2

11:30-11:50am 85 ChanAlignment of multi-walled carbon nanotubes on a silicon

substrate using an alignment relay technique

11:50-12:10pm 90 Abdulla The Analysis of Carbene-Stabilized Phosphorus(I) Cations

Room

ID Name Title

10:30-10:50am 28 GillSynthesis and characterization of hydrophobic In-fumarate

metal-organic frameworks

10:50-11:10am 30 Gray TiO2 Graphene Hybrids

11:10-11:30am 46 HungCatalytically Active Silicon Hydride Nanosheets for CO2

Reduction

11:30-11:50am 100 FerragSynthesis and characterization of high-swelling hydrogels

of Polyacrylamide and Polyvinylpyrrolidone cross-linked

with N-methylenebisacrylamide

11:50-12:10pm 105 ClassenSynthesis of Thermo-responsive and Self-immolative

Polymers from Poly(ethyl glyoxylate)

IN/M 2

BA111

GEN 1

BA211

IN/M 1

BA110

Room

ID Name Title

1:40-2:00pm 47 KiteleyExploring Alternative Methods for the Synthesis of

Difunctional Germanes

2:00-2:20pm 68 NascimentoDiscovering Frustrated Lewis Pairs Through Phosphenium

Cations

2:20-2:40pm 72 LyBright electrochemiluminescence from carbon quantum

dots at low costs

2:40-3:00pm 99 KooSynthesis of Novel Benzosiloles as Electrochemiluminescent

chromophores

3:00-3:20pm 135 LabinePhotoelectrochemical Reduction of Carbon Dioxide using

Mesoporous Titanium Dioxide Modified with Copper

Nanoparticles.

Room

ID Name Title

1:40-2:00pm 17 BraithwaiteThe Effects of Hydrogen Peroxide on the Corrosion of

Simulated Spent Nuclear Fuel (SIMFUEL)

2:00-2:20pm 44 ParkPhosphine Michael Addition to Maleimides for Nanomaterial

Modification

2:20-2:40pm 53 Nguyen Conductive Stretchable Fibres for Imperceptible Electronics

2:40-3:00pm 57 Nilsson Hemilabile NHCs for Oxidation Chemistry with Ni(II)

3:00-3:20pm 81 NoadeAlumina Sol Gel and Polydimethylsiloxane Composite

Interlayers for Increased Stretchability in Deformable

Electronic Devices

Room

ID Name Title

3:50-4:10pm 12 Poisson“Smart” self-assembled chromogenic materials on

enhanced screen printed nanosurfaces.

4:10-4:30pm 20 PetrovskiPurification of Fullerenes by Flash Column Chromatography

with Functionalized Iptycene onto Silica Gel

4:30-4:50pm 92 McLaughlinInert-Bond Activation Using a Pentanuclear Nickel Hydride

Cluster

4:50-5:10pm 102 Ravichandran Determination of Phosphonium Salt Dissociation Constants

5:10-5:30pm 134 PottierN-Heterocyclic Carbene Ligated t-Butylthiolates of Ag(I)

and Cu(I)

IN/M 5

BA110

IN/M 3

BA110

IN/M4

BA111

Room

ID Name Title

3:50-4:10pm 10 RielAdsorption Studies on Carbon Substrates: Quantification of

Glucose

4:10-4:30pm 55 StephensReactivity Studies of a Stabilized Low-Coordinate Palladium

Complex

4:30-4:50pm 65 RazumkovSynthesis of New Phosphorus-containing Functional Groups

Using 2-Phosphaethynolate Anion

4:50-5:10pm 70 St. Onge Utilization of Pincer Ligands in Main Group Chemistry

5:10-5:30pm 118 SuhReactivity and Tuning of a Pentanuclear Nickel Carbide

Cluster

Room

ID Name Title

10:30-10:50am 8Del Mundo

Cruz

Exploring the Diels-Alder Reaction for Structured Silicone

Materials

10:50-11:10am 48 Dickson Insertion of Electrophilic Alkynes into Silylamines

11:10-11:30am 111 BurtonDomino Palladium–Hydride Insertion/C–H Bond Activation:

Cycloisomerization of 1,6-Diynes

11:30-11:50am 119 Bridge Progress Toward the Formal Synthesis of Chanoclavine I

11:50-12:10pm 122 Desai Synthetic Approach to Produce a C-glycoside Tn Antigen

Room

ID Name Title

1:40-2:00pm 67 WojtkiewiczIncreasing Stretchability of Conjugated Polymers Using

Metal-Ligand Coordination

2:00-2:20pm 96 PalDiastereoselective Preparation of Chiral Amino Sulfoxides

Through Sulfenate Chemistry

2:20-2:40pm 103 JeevaSynthesis of New Reactive BODIPY Dyes and their

Applications in Solar Cells

2:40-3:00pm 125 Kapeniak Expanding the Role of CO2 Surrogates in Organic Synthesis

3:00-3:20pm 132 Liu Synthesis of sugar-derived aryl ethers

OR 2

BA112

IN/M 6

BA111

OR 1

BA112

Room

ID Name Title

3:50-4:10pm 35 Short Synthesis of indol-annulated S-containing polycycles

4:10-4:30pm 37 RamserranOptimization of an Enantioselective Desymmetrization of

Malonamides via Intramolecular Buchwald-Hartwig Cross-

Coupling Reaction

4:30-4:50pm 40 PowellExtending π-Conjugation in Boron Difluoride Formazanates

via Sonogashira Coupling

4:50-5:10pm 109 SammonsCyclization and Characterization of cis-1-alkenyl β-

aminoalkyl sulfoxides

5:10-5:30pm 139 BotelhoA New Method for the Activation of Donor-Acceptor

Cyclopropanes

Room

ID Name Title

10:30-10:50am 124 ReidEnzyme Encapsulation and Immobolization of

Deoxyribonuclease 1

10:50-11:10am 86 KailassRatiometric Fluorescent Chemosensing Carboxylesterase 2

Activity

11:10-11:30am 98 ChorolovskiCharacterization of a unusual transcription factor in the

protist, Giardia intestinalis

11:30-11:50am 117 FatimaTemporal and Spatial Expression of Giardia intestinalis

Flavohemoglobin

11:50-12:10pm 24 KrekhnoGene expression analysis of three isotypes of cytochrome

b5 during encystation of Giardia intestinalis

Room

ID Name Title

1:40-2:00pm 6 BickersNuclear Magnetic Resonance Studies of RNA Aptamer-

Fluorophore Complexes

2:00-2:20pm 29 Butler Role of RNase L in Cellular Stress-Induced RNA Disruption

2:20-2:40pm 36 AbdelrahimImproving phosphoprotein yield from an RNA-guided

genetic code recoding system in Escherichia coli

2:40-3:00pm 101 Bodagh Photoactivation of Inhibitors of Anti-Cancer Therapy

3:00-3:20pm 110 BahnamSynthesis and characterization of immunologically active

glycolipids isolated from S. pneumoniae

B/M 2

BA210

OR 3

BA112

B/M 1

BA210

Room

ID Name Title

3:50-4:10pm 2 Tajik Investigation into a Virus-Based Artificial Cellulosome

4:10-4:30pm 4 ShepherdsonEngineering a controlled environment within a spherical

capsule protein

4:30-4:50pm 11 ToDevelopment of Lysyl- and Alanyl-Phosphatidylglycerol

Synthesis to Investigate Bacterial Resistance to

Daptomycin

4:50-5:10pm 93 TanInvestigation on the Contribution of Electronic Effect of Mn-

Porphyrin-Based MRI Contrast Agents on T1 Relaxivity

5:10-5:30pm 115 TuFluorescent integrated stapled ghrelin(1-20) analogues for

the targeting of GHSR-1a in cancer

Room

ID Name Title

1:40-2:00pm 38 RickeardA Comparison and Contrast of Different Construction

Methods of Asymmetric Model Membranes

2:00-2:20pm 76 QureshiAnalysis of the Binding of Bifunctional Aptamers using

Isothermal Titration Calorimetry (ITC)

2:20-2:40pm 82 SchalikeNMR and Electrochemical Analysis of Bovine Cytochrome b5

G62 Deletion Mutant

2:40-3:00pm 107 QaqishSynthesis of the KRN 7000 Glycosphingolipid Acetal Free

Analogue

3:00-3:20pm

Room

ID Name Title

3:50-4:10pm 9 McCordThe Optimization of Enzymes for the Synthesis of Single

Chain Siloxane Phospholipids

4:10-4:30pm 13 PatelAnalyzing Biological Stability of Azobenzene-Containing

Short Interfering RNA

4:30-4:50pm 27 LazzamProbing Biofilm-Forming Bacteria with N-Acetyl

Glucosamine Analogues

4:50-5:10pm 78 LiEnzyme-powered Three-Dimensional DNA Walking Device

for Discriminating Single Nucleotide Variants

5:10-5:30pm 114 PalumboUsing Variable Temperature NMR to Examine the Structure

and Stability of Immature Human SOD1

B/M 5

BA211

B/M 3

BA210

B/M 4

BA211

Room

ID Name Title

10:30-10:50am 41 ChoiStructural and Mechanical Properties of Palm Oil in the

Presence of dispersed particulates

10:50-11:10am

11:10-11:30am 112 YeCan Molecular Simulations Help Understand Alzheimer's

Disease?

11:30-11:50am 113 AltenhofOptimal Control of Frequency-Swept Pulses for the

Acquisition of Ultra-Wideline Solid-State NMR Spectra

11:50-12:10pm 137 Cresswell Investigating Vibration-Plasmon Coupling in a Nanoreactor

Room

ID Name Title

1:40-2:00pm 15 De VlugtComputing Bound States of Rotor Chains and Arrays Using

Direct Operation and Renormalization Groups

2:00-2:20pm 25 OlechnowiczInvestigating CO2 Adsorption and Dynamics in the Metal-

Organic Framework ZnAtzOx-MeOH

2:20-2:40pm 43 HoDiscovering the structural stability of CAU-1 and its

properties for CO2 adsorption under extreme pressure by in

situ vibrational spectroscopy

2:40-3:00pm 59 LeGold Nanoclusters and Their Complexes: Experimental and

Computational Studies

3:00-3:20pm 80 LeEffect of Electrolyte Composition on Plasma Electrolytic

Oxidation Coatings on AM60 Magnesium Alloy

Room

ID Name Title

3:50-4:10pm 3 Lott A Novel Instrument for the Study of Gas Phase Ultrafast

Transient Absorption Dynamics in

4‑(N,N‑Dimethylamino)benzonitrile

4:10-4:30pm 23 SzukaloA molecular dynamics investigation on the interplay of

hydrophobic and hyrdrophylic interactions in an aqueous

droplet

4:30-4:50pm 50 LeggeProbing Surface Chemistry at the Monolayer Level with PM-

IRRAS

4:50-5:10pm 121 JosephCorrective method for density-functional calculations of

hyperfine coupling constants

5:10-5:30pm 127 MathersNaphthalene Dithioimides: Analysis of Steric Barriers to

Thionation

PCT 3

BA208

PCT 1

BA208

PCT 2

BA208

Room

ID Name Title

3:50-4:10pm 5 TullyInvestigation of the Permation of Hydrogen in X65 and X70

Carbon Steel

4:10-4:30pm 31 Laylo Electrocleaning Study of Daguerreotypes

4:30-4:50pm 56 NaveedNonlinear Phenomena in the Electrochemical Oxidation of

Bisulfite

4:50-5:10pm 106 MohammadThe Effect of Oxygen and Nitrite on the Corrosion of

Copper under Nuclear Waste Disposal Conditions

5:10-5:30pm 129 MirzoyanNear-field infrared spectroscopic properties of boron nitride

nanotubes upon polymer binding

Room

ID Name Title

10:30-10:50am 22 AlmusnedThe Role of Molybdenum in the Passivity of Ni-Cr-Mo Alloys

in Chloride Containing Environments

10:50-11:10am 26 KorkolaStudying the Folding of an Intrinsically Disordered Human

Protein Using Electrospray Ionization Mass Spectrometry

11:10-11:30am 32 KavuruUnderstanding Conformational Dynamics of Substrate

Binding to GST M2-2 using TRESI-HDX

11:30-11:50am 54 DeckertSelective molecular receptor for the detection and removal

of mercury ions from solutions.

11:50-12:10pm 88 Bulcan-GnirssA Study of the Fluorescent Properties of Rhenium -

Naphthalimide Conjugates

Room

ID Name Title

1:40-2:00pm 1 ShakeelDeveloping a Ligand–Modified Potentiometric Electrode for

the Detection of Aqueous Heavy Metal Ions

2:00-2:20pm 39 Li Chun FongA Biosensor for Au

3+ based on a DNAzyme and Iodide

2:20-2:40pm 58 WongThe Effects of Trivalent Chromium on Human Bladder

Cancer Cells Probed by Scanning Electrochemical

Microscopy

2:40-3:00pm 97 Maloney

Liquid Chromatography- Tandem Mass Spectroscopy

Method Validation and Analysis of Trichothecenes in

Agriculturally Relevant Wheat Samples

3:00-3:20pm 126 KatariaExamining the Effects of Oxidative Damage on Protein

Stability

AN 2

BA209

PCT 4

BA209

AN 1

BA209

#SOUSCC2018

Detailed Poster Schedule

poster # ID Name Title

1 14 Chen Effect of Substrate Surface Stiffness on Bacterial Adhesion

2 16 Fish

Assessing the Structural and Functional Characteristics of the

ADP/ATP Carrier Towards a Comparative Analysis with

Uncoupling Proteins

3 18 MathavarajahCln5 plays a role in adhesion, autophagy, cell differentiation,

and phagocytosis in Dictyostelium discoideum

4 19 BaoDevelop high efficiency electronic structure computational

method for solid state systems calculations

5 42 Leung

A novel enzyme based platform coupled to mass

spectrometry for the identification and screening of toxic

reactive metabolites from anti-thyroid drugs

6 45 AngelucciMeasurements of Atmospheric HCl in Toronto To Understand

Reactive Chlorine Chemistry

7 49 NeterThe Synthesis and Characterization of Alkynyl Substituted

Dibenzanthracenes

8 52 HungStimuli Responsive Hydrogels and their Self-Shaping

Applications

9 60 MoranTowards the synthesis of fluoro-substituted

dibenz[a,c]anthracenes using the Wittig reaction

10 61 Baig

The Use of Microfluidic Chemostats for the Observation of

Conjugation between Escherichia coli S17-1 and BL21(DE3)

pLysS Strains

11 62 AsifOptimizing a Decay Vessel for Continuously Monitoring the

Progression of Soft Tissue Decay in the Laboratory

12 64 KellerBorinic Acid Catalyzed Ring-Opening of an Acyclic 3,4-Epoxy

Alcohol using Substituted Aniline Nucleophiles

13 66 DaoUrea-linked Polymerization of Primary Amino Porphyrin

Complexes in Mild Conditions with CO2

14 69 WongInvestigation of Protein Folding, Aggregation and Substrate

Binding Sites Using High Resolution Mass Spectrometry

15 71 KynePoly(norbornene) Dopamine Polymer Electrode for Lithium

Storage

16 73 NardangeliApplication of Reductive Transposition in the Synthesis of

Pancratistatin

poster # ID Name Title

17 74 Schroeder Mild Metal Mediated Cyclization of a Thiourea to a Substituted

2-Aminobenzothiazole

18 75 Thomson Total Synthesis of (-)-Oxycodone

19 77 Lee Nickel-Catalysed Aminations of Diaryl Ethers

20 89 ColomboOptical biosensing of oligonucleotide modified gold

nanoparticles by induced DNA disassembly

21 94 RiddellExploring and optimizing sulfenate alkylation reactions for

applications in natural product synthesis

22 95 FramePreparation of Various β‑Amino Iodides and Bromides for

Alternative Synthetic Approaches to Sulfenate Substitution

23 104 DionisiSynthesis of Cyano-substituted carbene-stabilized

phosphorus(I) cations

24 108 WongDevelopment of a Next Generation Covalent MRI Tag Based

on Manganese Porphyrin

25 116 Jurkiewicz

The secondary structure and membrane association of the M2-

subdomain of TOC159, a protein of the chloroplast outer

membrane

26 120 AdrianoSynthesis of Supramolecular Vanadate Receptors – Structural

Mimics of Vanadium Haloperoxidase

27 123 ZhaoRemarkably High Stabilities of MnTCP: A Non-Gd Extracellular

MRI Contrast Agent

28 128 OlsonSynthesis and Characterization of Mn(I) Complexes for

Asymmetric Polar Bond Reduction

29 131 Mashmoushi Determining the Calcium Bound Structure of Daptomycin

30 133 PatelCrystallization of a Putative Polysaccharide Lyase TDE0626

from Treponema denticola

31 136 NguyenCharacterization of a GH88 Family Glucuronyl Hydrolase from

Tannerella forsythia

32 138 Farac

Synthesis and Characterization of Novel Copper(I) and

Nickel(II) Complexes with a Tetradentate Bis(amino)-Bis(N-

heterocyclic carbene) (CNNC) ligand

#SOUSCC2018

Oral Presentation Abstracts

1 - Developing a Ligand–Modified Potentiometric

Electrode for the Detection of Aqueous Heavy Metal Ions

Zainab Shakeel1, Bryan Koivisto1

1Ryerson University

The rapid detection of heavy metal contaminants such as cadmium, lead, and mercury

present in our water supply is of great importance. Traditional analytical tests designed

to detect these metals use expensive instruments that are time-consuming and

challenging to maintain. To improve analytical testing, handheld analytical devices have

recently gained popularity with market demand projected to reach $9.55 billion USD by

2020 from $8.10 billion USD in 2015, as these provide a user friendly and economically

feasible alternative that delivers instantaneous results. The purpose of this study is to

develop a means to perform both quantitative and qualitative analysis using a spectro-

electrochemical cell. Our heavy metal-detecting device would be comprised of a

phosphorylated heavy metal chelating ligand that is anchored onto titania (TiO2), and is

connected in series to a voltmeter that measures changes in voltage resulting from a

metal binding event.

Current efforts in metal detection involve maximizing binding affinities of the ligand to

Pb2+, Hg2+, and Cd2+ ions, which are soft Lewis acids. In this study, we present our

ligand that pursuit to introduce target-specific binding using nitrogen, oxygen, and sulfur

atoms.

2 - Investigation into a Virus-Based Artificial

Cellulosome

Amanda Tajik1, Taylor Urquhart1, John Honek1

1University of Waterloo

Bacteriophage M13 (dimensions 6 nm x 900 nm) are Escherichia coli targeting viruses,

which have been extensively investigated for applications in phage display. Both

chemical modifications and amino acid mutations can be made to the coat proteins of

M13 without affecting assembly of the viral coat. The current project seeks to employ the

major M13 coat protein, pVIII (2700 copies per phage), for the development of novel

nanodimensional multienzyme complexes, specifically in this case, an artificial

cellulosome. Cellulosomes are multienzyme complexes capable of breaking down

cellulose, which is regularly resistant to facile degradation. Variation of cellulosome

enzyme composition has been shown to control cellulolytic efficiency in natural systems.

A strategy based on the chemical modification of M13 followed by scaffold extension

employing streptavidin-biotin clusters attached to cellulases is being investigated. If

successful, this approach may lead to the fabrication of novel virus-based composite

materials capable of highly controllable cellulolytic activities, allowing for more efficient

harnessing of the energy stored within biopolymers.

3 - A Novel Instrument for the Study of Gas Phase

Ultrafast Transient Absorption Dynamics in

4‑ (N,N‑ Dimethylamino)benzonitrile

Tyler Lott1, Nicolas Rivas1, Ariel Petruk1, Kostyantyn Pichugin1, Germán Sciaini1

1Ultrafast Electron Imaging Laboratory (UeIL), Department of Chemistry, and Waterloo

Institute for Nanotechnology (WIN), University of Waterloo

4‑ (N,N‑ Dimethylamino)benzonitrile) (DMABN) has drawn significant interest within the

field of physical chemistry over the past 60 years. The remarkable dual fluorescent

behaviour which is commonly known to exist has led to many studies concerned with the

characterization and the description of the locally excited (LE) and intramolecular charge

transfer (ICT) states. In particular, the ICT states are the most remarkable and many

contributions have been made and continue to be made to explore the dynamics of

excitation and relaxation. Most notably, fluorescence and transient absorption

measurements have been thoroughly conducted in the condensed phase with limited

experimental research produced to investigate gas phase dynamics. Through a unique

approach to instrumental design, a cell capable of gas phase spectroscopic

measurements has been constructed. Through the employment of femtosecond

transient absorption techniques, the uniquely designed gas-cell is utilized to investigate

the excited state dynamics of DMABN in various gaseous mediums.

4 - Engineering a controlled environment within a

spherical capsule protein

Evan Shepherdson1, Hawa Gyamfi1, John Honek1


Bionanotechnology has tremendous potential to improve current drug discovery

programs through the development of new platforms and strategies for delivery at the

nanoscale. This can be especially critical in the delivery of hydrophobic therapeutics.

Engineering better delivery platforms can serve to stabilize and protect labile compounds

from degradation, increase the solubility of hydrophobic drugs, and preferentially deliver

cargo to specific tissues. Current platforms being explored in this area include

liposomes, micelles, dendrimers, and nanoparticles. Spherical capsule proteins, such as

viral capsids and iron-storage proteins, are naturally evolved complexes, that self-

assemble into defined structures and are controllable by a combination of bioconjugation

as well as genetic strategies. The current project is to explore approaches to engineer

the hydrophobicity of the interior cavity of a nanodimensional (12 nm) spherical capsule

protein and to explore the chemistry and biochemistry of these molecular spaces.

Approaches to the controllable encapsulation of defined micelles by the host capsule

protein will be presented and a discussion of the impact that the structure of the micelle

as well as the protein has on the resulting nanocomposite will be provided.

5 - INVESTIGATION OF THE PERMEATION OF

HYDROGEN IN X65 AND X70 CARBON STEEL

Claire Tully1, Maxwell Goldman1, David Shoesmith1, James Noël1

1The University of Western Ontario

X-series carbon steel (X65 and X70) is used for transmission pipelines in the oil and gas

industry. Pipelines are typically protected from the environment by applying either a

coating or cathodic protection. Applying too much current during cathodic protection can

cause atomic hydrogen to diffuse into the steel, resulting in embrittlement, blisters, and

cracks. We investigated the rate of hydrogen diffusion using the Devanathan-Stachurski

method.Calcium and magnesium were introduced to simulate groundwater conditions

and to determine their role on the rate of hydrogen absorption into X-series steels.

Calcium was found to cause a sharp decrease in the permeation of hydrogen, due to the

formation of calcium carbonate deposits on the steel surface, whereas, magnesium

caused a gradual decrease in the rate of hydrogen absorption, likely due to the

thickening of the magnesium hydroxide film on the steel surface. The permeation of

hydrogen into the steel affects the physical properties of the steel, and trapped hydrogen

may affect the passive properties of an iron oxide formed on the steel surface. Linear

polarization resistance measurements were used to measure the resistance of the

surface oxide. The measured resistance of the oxides formed on the X65 and X70

showed that hydrogen charging had a more pronounced effect on the X65 than on the

X70.Once the hydrogen enters the metal, no solution species can affect its diffusion

within the metal.

6 - Nuclear Magnetic Resonance Studies of RNA

Aptamer-Fluorophore Complexes

Sarah Bickers1, Kyle Piccolo1, Thorsten Dieckmann1

1Department of Chemistry, University of Waterloo

Aptamers are single stranded oligonucleotides selected in vitro to bind target ligands

with high affinity and specificity for various applications. Using SELEX, the RNA aptamer

SRB-2 was selected to bind the sulforhodamine B fluorophore for potential use in cellular

RNA imaging. Fluorophore aptamers bind fluorescent dyes predominantly through π-

stacking and electrostatic interactions, requiring target molecules to share similar

structure and charges. Uniquely, SRB-2 recognizes and binds additional fluorophores—

sulforhodamine 101, rhodamine B, and tetramethylrosamine—which all differ in

molecular charge and charge distribution. The different molecular electrostatics suggests

SRB-2 binds each dye through residue specific interactions and distinct binding modes.

Identification of residues involved in aptamer binding provides the foundation for

enabling modification of dye substituents to increase binding efficacy and stability for in

vivo localization of RNA. Utilizing 1D and 2D NMR techniques, preliminary site specific

information of analogous and characteristic aptamer-dye interactions were obtained

through comparison of SRB-2 in absence and in complexation with the dyes.

8 - Exploring the Diels-Alder Reaction for Structured

Silicone Materials

Jaaziel Del Mundo Cruz1, Paul M. Zelisko1

1Brock University, Department of Chemistry and Centre of Biotechnology, 1812 Sir Isaac

Brock Way, St. Catharines, Ontario L2S 3A1

Thermoset materials, unlike thermoplastics, are far superior in their mechanical and

physical properties because they are cross-linked materials (i.e. the polymers are

covalently bonded to each other). As a result, thermosets cannot be melted and

remoulded, making recycling them quite difficult. With the aid of Diels-Alder (DA)

reaction, this problem of recyclability can be addressed. Depending on the dienophile

and the diene, the reaction should go forward at a certain temperature to form an adduct

where the starting materials are covalently bonded. If the material is damaged, at

another temperature (usually higher), the starting materials can be recovered (retro-DA),

and the forward reaction can be performed once again to regenerate the bonds between

the polymer strands. In this project, a maleimide and a furan will be employed, as the

dienophile and diene, respectively, and will be used to functionalize siloxane polymers.

As an added environmental benefit an enzyme, Novozym-435, was used to perform

some of the key chemical steps in the synthetic pathway of the recyclable siloxanes. The

compounds were analyzed using 1H NMR, 13C NMR and 29Si NMR.

9 - The Optimization of Enzymes for the Synthesis of

Single Chain Siloxane Phospholipids

Kelli McCord1, Paul Zelisko1

1Brock University, Department of Chemistry and Centre for Biotechnology, 1812 Sir

Isaac Brock Way, St. Catharines, Ontario L2S 3A1

The use of enzymes for biocatalysis is a very promising area of research as it presents a

greener alternative to harsh, non-renewable, metal-based catalysts that are commonly

used. Specifically, lipases can eliminate the need for organic solvents in a reaction and

are naturally occurring so they act as a renewable source of catalytic material. The

efficiency and selectivity of lipases in the chemoenzymatic synthesis of organic and

silicon-containing single chain phospholipids was assessed. Siloxane-containing lipids

have been shown to self-assemble into ≈120nm unilamellar vesicles (ULVs), and as a

result have a great deal of potential for drug delivery and surface modifications.

Immobilized lipases from C. antarctica (B and A), R. miehei (RM) and T. lanuginosa (TL)

were used for catalysis in two main lipid syntheses. In both reaction schemes

glycerophosphocholine (GPC) was combined with a 10-fold excess of either organic

palmitic acid or the organosiloxy 5-(1,1,3,3,3-pentamethyldisiloxanyl)pentanoic acid. The

efficiency and selectivity of a variety of lipases in performing these chemical

transformations was assessed through 31P NMR and 1H NMR. Due to the differences in

the active sites of the four lipases it was expected that the enzymes would yield products

differing in preference for the sn1 position or the sn2 position. To our knowledge this is

the first extensive research being done to determine the efficiency or selectivity of

lipases in phospholipid synthesis. The ultimate goal of this research is to increase the

efficiency and selectivity of siloxane phospholipid synthesis.

10 - Adsorption Studies on Carbon Substrates:

Quantification of Glucose

Donna Riel1, Dario Bonetta1, Liliana Trevani1

1Faculty of Science, University of Ontario Institute of Technology.

The purpose of this project was to identify and optimize a method for the quantification of

glucose in aqueous solutions. This is advantageous in studying the adsorption of

glucose on different carbon substrates since previous studies have shown glucose, a

highly hydrophilic molecule, can be used to change the surface wetting properties of

carbon (Odetola et al., Int. J. Hydrogen Energy, 41(19), 8199-8208, 2016). This is a

preferred step in the synthesis of hybrid carbon/metal oxide materials.

Different methods for the determination of glucose in aqueous solution were analyzed as

a first step for glucose adsorption kinetics and thermodynamic studies. Our results have

shown that the determination of glucose using gas chromatography after derivatization

of glucose into volatile alditol acetates (Blakeney et al,Carbohydrate Research, 113,

291-299, 1983) is a suitable approach for these studies. It has the required sensitivity for

the quantifiation of glucose before and after adsorption onto carbon.

Two high surface area carbon substrates, activated carbon (Darco KB-G) and carbon

black (VulcanÒ XC-72), have been used to validate the proposed method. A detailed

description of the method, and preliminary adsorption data will be discussed.

11 - Development of Lysyl- and Alanyl-

Phosphatidylglycerol Synthesis to Investigate Bacterial

Resistance to Daptomycin

Avery To1

1Department of Chemistry, University of Waterloo

Daptomycin (Dap) is an important last-defense antibiotic used in clinic to treat serious

infections caused by Gram positive bacteria. It is a cyclic lipodepsipeptide consisting of a

10 amino acid macrocyclic peptide core containing an ester linkage, to which is attached

a lipidated linear tripeptide. Its activity is Ca2+-dependent in that it must bind Ca2+ in

order to be active. Further, its target site is the bacterial cell membrane where

phosphatidylglycerol (PG) must be present for activity. While resistance to Dap is not yet

common, the number of reports describing Dap-resistant bacterial strains from clinical

isolates is increasing yearly. One mechanism by which bacteria develop resistance

against Dap is by increasing the amount of lysyl-phosphatidylglycerol (LPG), a cationic

PG derivative, in their cell membranes. How LPG confers resistance is not known with

certainty. Some studies suggest that it prevents Dap from

inserting into the membrane as a result of electrostatic repulsion between Ca+2-bound

Dap and LPG. However, other studies have shown that the presence of alanyl-

phosphatidylglycerol (APG) in bacterial membranes may also be capable of conferring

resistance to Dap. This suggests that aminoacyl PGs may confer resistance simply by

reducing the amount of PG in the membrane. We wish to study the effect of LPG and

APG on Dap membrane binding. LPG and APG are commercially available; however,

both are prohibitively expensive. Two inefficient and lengthy syntheses of LPG were

reported in the late 1960’s. Here we present more efficient syntheses of these

aminoacyl PGs using modern phosphoramidite chemistry.

12 - “Smart” self-assembled chromogenic materials on

enhanced screen printed nanosurfaces.

Jade Poisson1, Simone Quaranta1, Nadia O Laschuk1, Iraklii I Ebralidze1, Franco

Gaspari1, E. Bradley Easton1, Olena V Zenkina1

1University of Ontario Institute of Technology

Nanoparticle conductive or semi-conductive films allow for the unique optical

properties of inorganic and organometallic complexes to be in the solid state while

retaining the redox activity of the species. Many inorganic and organometallic complexes

have unique optical properties that lend to distinctive properties in the films. Herein, we

investigated the stability and optical properties of osmium (II) and iridium (III) complexes

functionalized via a silane linkage onto various nanoparticle substrates including indium

doped tin oxide (ITO, of varying diameter), aluminum doped zinc oxide (AZO) and

antimony doped tin oxide (ATO). The nanoparticles were screen-printed onto ITO-coated

glass films. Functionalization occurred via a monolayer self-assembly mechanism and

demonstrated distinct change in optical properties upon the application of a potential.

The osmium complex presents electrochromic properties and the iridium complex

presents luminescent and electrochromic properties. Both complexes underwent metal

to ligand charge transfer resulting in a colourless (oxidized) and coloured (reduced)

state.

The samples were characterized through many methods including differential pulse

voltammetry (DPV), cyclic voltammetry (CV), electrochemical impedance spectroscopy

(EIS), surface area analysis (BET). The stability/kinetics were indicated by

spectroelectrochemistry (SEC). Upon analysis of the films it was determined that the ITO

(<50 nm) nanoparticles provided the largest reductive/oxidative efficiency with a

moderate surface area. Future work would involve the combination of these optical

properties onto a single film. Combined, the films would have the ability to switch

between different optical properties with varied applied potential.

13 - Analyzing Biological Stability of Azobenzene-

Containing Short Interfering RNA

Ayushi Patel1, Matthew Hammill1, Jean-Paul Desaulniers1

1University of Ontario Institute of Technology

The RNA interference (RNAi) pathway is an endogenous process that regulates gene

expression. In this process, double stranded RNA (dsRNA) gets cleaved into small

interfering RNA (siRNA) which triggers the degradation of the mRNA that matches its

sequence. From this discovery, siRNAs have gained a lot of interest for potential

therapeutic treatment, including cancer. This technology of treating cancer is optimal

because of selective targeting; siRNAs can target and kill tumor cells, whereas the

healthy cells remain unaffected. However, there are limitations to using siRNA as

therapeutic treatment because of the native structure of the siRNA. As a result, chemical

modifications are incorporated into the siRNA to overcome such challenges. In this

study, siRNAs are modified with a photoregulated molecule, azobenzene, in the

phosphate backbone. The biological functionality of azobenzene-modified siRNA

(siRNAzo) can be controlled, in an on/off manner. In the presence of different

wavelengths, azobenzene groups isomerizes which alters the conformation of the

siRNA. In the presence of visible light, azobenzene is in trans conformation (active state)

and in the presence of UV (ultraviolet) light, azobenzene is in cis conformation (inactive

state). The siRNAzos were tested against firefly luciferase using gel electrophoresis to

determine exonuclease stability. Our results indicate that siRNAzo in the cis

conformation have enhanced exonuclease resistant compared to the trans conformation.

15 - Computing Bound States of Rotor Chains and

Arrays Using Direct Operation and Renormalization

Groups

Isaac De Vlugt1, Dmitri Iouchtchenko1, Tom Halverson1, Pierre-Nicholas Roy1


A direct operation Lanczos method is proposed for the calculation of energy levels for

linear and nonlinear nano-molecular assemblies of endofullerenes. The specific system

of interest is that of rigid HF encapsulated in C60, where only screened dipole-dipole

interactions and rotational energy terms are considered in the Hamiltonian. A

comparison is drawn between employing direct operation and explicitly constructing the

Hamiltonian matrix and evaluating matrix-vector products in a Lanczos algorithm for the

linear systems. Direct operation is shown to out-perform the matrix-vector product

method for large basis sizes. Additionally, renormalization groups at the two-dipole level

are explored theoretically and computationally and are shown to not scale well with

system or basis size.

17 - The Effects of Hydrogen Peroxide on the Corrosion

of Simulated Spent Nuclear Fuel (SIMFUEL)

Lindsay Braithwaite1, Ziyan Zhu1, David W. Shoesmith1, James J. Noel1

1University of Western Ontario

Spent UO2-based nuclear fuel deposited in a deep geological repository may be

exposed to oxidizing conditions in the event of container failure. Radiolysis of

groundwater which reaches the fuel surface will produce many products including the

oxidant hydrogen peroxide (H2O2), which is expected to cause UO2 corrosion. Noble

metal fission products in the spent fuel congregate into ε particles, which could catalyze

H2O2 decomposition. The goal of this project is to use electrochemical experiments to

investigate the effect of ε particles on H2O2-induced fuel corrosion and H2O2

decomposition on the fuel surface.

The working electrodes were UO2 SIMFUEL pellets; one doped with 7 rare-earth metals

and one doped with 4 noble metals and 7 rare-earth metals. Corrosion of each electrode

in solutions of 10-4 M to 10-2 M H2O2 was monitored over 24 hours using corrosion

potential and linear polarization resistance measurements. The corrosion potential was

confirmed to be dependent on H2O2 concentration. By measuring concentration changes

in H2O2 and dissolved U by UV-Vis spectrophotometry and inductively coupled plasma-

mass spectrometry, respectively, the dominant mechanism of H2O2 consumption was

found to be decomposition on the UO2 surface rather than UO2 oxidation. Cyclic

voltammetry experiments revealed that the kinetic current produced by H2O2 reduction

on the SIMFUEL surfaces is higher in the presence of ε particles. Tafel slopes produced

from cyclic voltammetry data show that the mechanism of H2O2 reduction is the same

with or without ε particles and the initial chemical oxidation of UO2 by H2O2 is rate

determining.

20 - Purification of Fullerenes by Flash Column

Chromatography with Functionalized Iptycene onto

Silica Gel

George Petrovski1


Fullerenes have unique properties that have been exploited in renewable energy

sources as well as a variety of applications for future technology. Commercialization of

fullerenes is not yet possible due the difficulty of obtaining vast amounts of pure

fullerenes. When fullerenes are made, a variety of carbon allotropes are made along

with fullerenes. However, to apply fullerenes into technology, a certain level of purity is

required. Previously in the Schipper lab a flash chromatography method was devised to

purify fullerenes. The problem was that the purification worsened with repeated runs

because the molecule used for the purification were unstable and degraded over many

uses so we hypothesized that functionalizing large aromatic molecules onto silica gel

with stronger bonds holding the molecules on the silica gel.

21 - Nickel & Palladium (N,O)-Donor Ligand Complexes:

Structure & Catalysis

Jeanette Adjei1, Alan J. Lough2, Robert A. Gossage1

1Ryerson University, 2University of Toronto

2-Oxazolines are a subclass of azole heterocycles, its ring structure consists of a

nitrogen and oxygen atom which are connected via an sp2-hybridized carbon atom.

Oxazoline ligands has garnered attention due to its versatility as a synthetic intermediate

and metal binding agent used extensively in homogenous catalysis. The Gossage group

has explored the coordination capabilities of oxazoline to transition metals via N, O

chelation; of which has resulted in various oxazoline based metal complexes. Particular

complexes have shown the ability to catalyze carbon-carbon bond formation. Currently,

Group 10 transition metals such as nickel and palladium are of current interest to the

Gossage group due to their prevalence in catalysis. This research project focuses on the

synthesis, characterization and coordination chemistry of a series of novel and existing

bidentate oxazoline ligands. The synthesis of these ligands employs facile approaches in

which the ligands are generated in two steps. Additionally, recrystallization is utilized as

a purification method over the expensive and time-consuming column chromatography.

Finally, the resulting palladium and nickel complexes are characterized via

electrochemistry, crystallography and UV-Vis. The catalytic activities of the palladium

and nickel complexes for Suzuki cross-coupling and polymerization chemistry are

explored, respectively.

22 - The Role of Molybdenum in the Passivity of Ni-Cr-

Mo Alloys in Chloride Containing Environments

Baian Almusned1, Jeffrey D. Henderson1, Martin Badley1, Brad Kobe2, James J Noel1,2,

David W. Shoesmith1,2

1University of Western Ontario, 2Surface Science Western,

Nickel alloys, containing various amounts of Cr and Mo, are known to withstand a wide

range of corrosive media and, thus, may replace conventional steels in aggressive

industrial applications. The widespread application of these alloys necessitates research

to better characterize the role of individual alloying elements, with the ultimate goal of

optimizing alloy composition. Additions of Cr are known to promote the formation of an

inert, protective (passive) oxide film which enforces low corrosion rates. While the oxide

decreases the general corrosion rate, the film can be susceptible to breakdowns at

discrete sites (i.e., localized corrosion), where metal dissolution can then rapidly occur.

Crevice corrosion, occurring between surfaces in contact, is the most likely form of

localized corrosion for Ni-Cr-Mo alloys exposed to hot chloride-containing environments.

Additions of Mo are known to increase resistance to localized corrosion, although the

exact mechanism by which this occurs remains unresolved.

The motivation of this research is to better understand how compositional changes (i.e.,

the Cr/Mo ratio) influence the corrosion resistance of alloys exposed to anticipated

localized corrosion environments. A series of electrochemical and surface analytical

techniques have been applied to the investigation of the behaviour of four commercially

available Ni-Cr-Mo alloys under simulated crevice conditions. The techniques employed

include corrosion potential, potentiodynamic, and potentiostatic measurements,

electrochemical impedance spectroscopy, X-ray photoelectron spectroscopy, and time-

of-flight secondary ion mass spectrometry.

23 - A molecular dynamics investigation on the interplay

of hydrophobic and hyrdrophylic interactions in an

aqueous droplet

Ryan Szukalo1, Styliani Constas1


An investigation of the how the hydration mechanism of typically hydrophobic solutes

react when charge is introduced is of fundamental importance when attempting to design

new nanomaterials for applications involving aqueous environments. Although rich

literature has been conducted on the hydrophobic effect, the buckyball represents a

boundary condition case where neither small or large hydrophobic solute theory can be

directly applied, as both the kinetics and thermodynamics do not obey either large or

small criteron of the hydrophobic effect. A further advantage to studying the C60

buckyball is it's structure represents the building block for an entire class of carbon

nanotubes, rich with application in aqueous environments. We used molecular dynamic

simulations of systems containing both neutral buckyballs and charged buckyballs at the

interface of a water nanodroplet containing up to 2000 water molecules, with sodium

counterions to balance the net system charge. These systems were used to probe how

hydrophobic solutes equilibriate on a surface, on how this process changes upon the

addition of realistic charge values.

24 - Gene expression analysis of three isotypes of

cytochrome b5 during encystation of Giardia intestinalis

Zakhar Krekhno1, Janet Yee1

1Trent University

Giardia intestinalis is an important waterborne parasite that infects around 280 million

people worldwide. It causes a disease called giardiasis, with symptoms including

diarrhea, vomiting and abdominal pain. Giardia exists in two different lifeforms, an active

trophozoite and an infectious cyst, and the process of encystation (transforming from

trophozoite into a cyst) has long been a target for anti-giardiasis therapy. Cytochromes

b5 are heme-containing proteins involved in electron transport processes of eukaryotes.

Giardia lacks heme-biosynthetic enzymes and does not possess mitochondria, where

heme biosynthesis occurs, nor does Giardia possess electron transfer partners of

cytochrome b5 that are commonly found in other eukaryotes. Consequently, the fact that

its genome encodes for four isotypes of cytochrome b5 is intriguing., As the roles of the

Giardia cytochromes b5 are likely unique to this organism, the pathways they are

involved in can potentially be targeted for anti-giardiasis treatment. Our lab has

previously examined protein levels of cytochrome b5 isotypes I, II and III during

encystation, and found that cytochrome b5-II is upregulated 4-fold, indicating a possible

involvement of this protein in encystation. However, a recent RNA-sequencing analysis

performed by another research group indicated that cytochrome b5-II mRNA levels

decreased during encystation. In this study, I used quantitative RT-PCR (RT-qPCR) to

analyze mRNA levels of the three Giardia cytochromes b5 isotypes and a nitric oxide-

detoxifying flavohemoglobin during encystation and showed that cytochrome b5-II is

upregulated early in the process. I will discuss possible reasons for discrepancies in our

RT-qPCR results and the results from RNA-sequencing.

25 - Investigating CO2 Adsorption and Dynamics in the

Metal-Organic Framework ZnAtzOx-MeOH

Maya Olechnowicz1, Bligh Desveaux1, Bryan Lucier1, Yining Huang1


Highly porous compounds, known as metal-organic frameworks (MOFs), have gained

significant attention due to their impressive performance in gas adsorption, separation,

and storage. In addition, there is an increased pressure to manage and reduce industrial

carbon dioxide emissions. Promising industrial gas storage capabilities of these

inorganic-organic hybrid compounds arise from their unique structural characteristics,

including record-breaking surface areas, high porosity levels and adjustable pore sizes.

This study focuses on the motions and dynamics of CO2 gas molecules within the

framework of the CO2-selective, ultra-microporous MOF ZnAtzOx-MeOH. The synthesis

of ZnAtzOx-MeOH was optimized and the product was confirmed using powder X-ray

diffraction (PXRD). The MOF was analyzed using variable-temperature (VT) solid-state

NMR in order to obtain information regarding CO2 adsorption behaviours within the

framework. The number of unique CO2 absorption sites were identified and simulated in

order to identify the dynamics of gas molecules at each site at different temperatures.

The results indicate that there are at least 3 unique adsorption sites within the framework

of ZnAtzOx-MeOH.

26 - Studying the Folding of an Intrinsically Disordered

Human Protein Using Electrospray Ionization Mass

Spectrometry

Natalie Korkola1, Martin J Stillman1

1Stillman Bioinorganic Group, Department of Chemistry, University of Western Ontario

It is well known that the structure of a protein is very important when it comes to

performing its function. The protein must be in its folded native conformation to be

active, but this structure can be unwound upon addition of a denaturant, which disrupts

the stabilizing bonds of the higher order structure. Many proteins however, do not

possess a well defined folded structure. Metallothionein is one of these disordered

proteins. In this study, the structure of apo metallothionein was probed using cysteine

modification with N-ethyl maleimide at pH 7.4 with and without the presence of the

denaturant guanidinium chloride. The modification patterns were monitored on an

electrospray ionization mass spectrometer [1]. It was found that the structure differed

depending on whether or not a denaturant was added, showing that apo metallothionein

does adopt a folded structure at biological pH. A method for the use of guanidinium

chloride for studies in mass spectrometry was also developed. The results were

compared with studies done on myoglobin: a well-understood protein with a defined

higher order structure. The myoglobin was denatured by pH adjustment, and the

changes in charge state were monitored by electrospray ionization mass spectrometry.

The myoglobin was found to display the expected patterns for the folded and unfolded

states.

For previous work, see:

[1] Irvine, G.W.; Santolini, M.; Stillman, M.J. Selective cysteine modification of metal-free

human metallothionein 1a and its isolated domain fragments: Solution structural

properties revealed via ESI-MS. Protein Sci. 2017, 26, 960-971.

27 - Probing Biofilm-Forming Bacteria with N-Acetyl

Glucosamine Analogues

Daniel Lazzam1, Benjamin DiFrancesco1, Adam Forman1, Mark Nitz1

1University of Toronto

Biofilm-forming bacteria present serious problems in many areas of society, from health

care to the food industry. The protective biofilm matrix that makes these problems so

significant is made up largely of polysaccharides; specifically, Poly N-acetyl

Glucosamine (PNAG). In an attempt to learn more about the formation of this polymer,

azide-tagged N-acetyl glucosamine (GlcNAc) analogues were synthesized and used as

substrate for PgaCD, the enzymes responsible for PNAG formation, in order to help

track polysaccharide formation and determine biosynthesis directionality, which we

determined to require addition to the non-reducing end of PNAG polysaccharide.

Furthermore, azide tagged GlcNAc-based metabolic analogues were fed to biofilm-

forming bacteria in order to track the various uses and fates of GlcNAc in bacteria,

particularly in cell wall biosynthesis in addition to biofilm formation. These results help

shed light on the interconnectedness of bacterial processes contributing to biofilm

formation and pathogenicity.

28 - Synthesis and characterization of hydrophobic In-

fumarate metal-organic frameworks

Karanpreet Gill1, Yue Zhang2, Bryan E. G. Lucier3, Yining Huang4

1University of Western Ontario, 2University of Western Ontario, 3University of Western

Ontario, 4University of Western Ontario

Metal-organic frameworks (MOFs) are versatile porous crystalline materials known for

their large surface area, high thermal stability, and excellent porosity. These properties

afford MOFs various applications in gas storage, catalysis, gas separation, and drug

delivery, among other fields. Synthesis of hydrophobic MOFs is of particular interest, as

water can decompose the framework or occupy binding sites for target molecules such

as CO2. Our research group previously determined that In-fumarate synthesized in

ethanol (In-fumarate-E) produced a hydrophilic MOF, but methanol solvent yielded a

hydrophobic product (In-fumarate-M).

In this study, additional hydrophobic In-fumarate MOFs were successfully produced via a

one-step synthesis or post-synthetic modification route. The use of NaF (In-fumarate-E-

NaF) or LiF (In-fumarate-E-LiF) in MOF synthesis produced crystalline In-fumarate

frameworks that adsorbed less H2O from the atmosphere in comparison to In-fumarate-

E, as shown using thermal gravimetric analysis (TGA). FTIR spectra suggests some of

the hydroxyl bridging groups connecting two indium metal centers in In-fumarate-E are

altered in the hydrophobic compounds. Solid-state NMR (SSNMR) experiments of the

post-synthetic modification product In-fumarate-E-to-M further supports this hypothesis.

SSNMR experiments of the In-fumarate-E-NaF MOF clearly indicate that Na is bound

and incorporated within the framework. The surface areas and CO2 adsorption

capacities of all MOFs within this study were also examined. These hydrophobic MOFs

show potential for practical applications involving the presence of H2O and serve as a

promising basis for the design of framework analogs.

29 - Role of RNase L in Cellular Stress-Induced RNA

Disruption

Phillipe Butler1, Amadeo M. Parissenti1,2,3,4

1Department of Chemistry and Biochemistry, Laurentian University, Sudbury, ON,

Canada, 2Health Sciences North Research Institute, Sudbury, ON, Canada, 3Division of

Medical Sciences, Northern Ontario School of Medicine, Sudbury, ON, Canada, 4RNA

Diagnostics Inc., Toronto, ON, Canada

30 - TiO2 Graphene Hybrids

James Gray1, Andrew Vreugdenhil1

1Trent University

Titanium dioxide graphene hybrid materials have been proposed as effective

photocatalysts as the graphene is expected to reduce the TiO2 electron-hole

recombination process. Graphene is a two-dimensional (2D) allotrope of carbon and is

typically classified as single, double, or few-layer graphene (FLG). The number of

graphene layers can dramatically change the material’s thermal and electrical

characteristics as well as other properties. In this work, a probe sonicator was used to

exfoliate graphene from graphite in the presence of an exfoliating agent in water. The

resulting graphene dispersion was characterized using Raman spectroscopy. Anatase

titanium dioxide (TiO2) was added to the graphene to generate a TiO2 graphene hybrid

using sonication or thermal processing. The photocatalytic activity of the resulting TiO2

graphene hybrid was explored through its catalysis of a standard photoreaction with

hydrogen peroxide and the decolouration of methylene blue solutions.

31 - Electrocleaning Study of Daguerreotypes

Patricia Laylo1, Madalena Kozachuk1, T.K. Sham1, James Noël1


Invented in 1839 by Louis-Jacques-Mandé Daguerre, the daguerreotype was the first

reproducible form of the photographic image. It launched a 30-year period known as

“daguerreotypomania” before being surpassed by other, more convenient imaging

methods. The production of a daguerreotype involves photosensitizing a silver surface

by reaction with selected halides, exposing the plate to the image (light), subsequently

developing it by exposure to mercury vapour, and fixing the image by removal of excess

photosensitive species. The daguerreotype appearance is due to the interaction of light

(reflection or scattering) with particles on the metal surface. Similar to other metallic

artifacts of this age and nature, daguerreotypes are prone to tarnish, and depending on

composition, the tarnish products can affect the appearance of the daguerreotype

differently. Historically, various daguerreotype preservation methods have been used.

While these methods result in visible improvement to the image, the surface of the

daguerreotype may be affected due to these conservation efforts. Most recently,

electrocleaning is proving to be a viable method of daguerreotype restoration, preserving

the image without affecting the surface. The purpose of this study was to develop a

further understanding of the chemistry behind the electrocleaning process, as well as the

chemistry of the daguerreotype itself. Surface analysis techniques used included optical

microscopy, scanning electron microscopy, inductively coupled plasma-mass

spectrometry and synchrotron X-ray spectroscopy. Three electrolytes were used in the

electrocleaning process: NH4OH, NaNO3 and Na3C6H5O7. From this examination, the

tarnish on the surface was identified and the optimal cleaning solution determined.

32 - Understanding Conformational Dynamics of

Substrate Binding to GST M2-2 using TRESI-HDX

Abhilash Kavuru1, Derek Wilson1

1York University

Glutathione S-Transferase (GST) is a large class of enzymes responsible for detoxifying

cells from reactive electrophilic xenobiotic species by conjugating them with reduced

glutathione (GSH). The GST superfamily consists of many isotypes (Alpha, mu, omega,

pi, sigma, theta and zeta) which exist as dimers (~50 kDa) and have mostly similar

structures. The mu class is characterized by a β2-α3 loop known as "mu loop". GST M2-

2 has prominent activity in detoxification of the dopamine metabolite, aminochrome and

other similar xenobiotes. The substrate binding interactions with GST M2-2 can be

understood using time-resolved electrospray ionization hydrogen deuterium exchange

(TRESI-HDX) to visualize how the conformation of the enzyme shifts as the substrate

binds. The HDX of GST M2-2 apoenzyme is compared with the HDX of M2-2 bound to

GSH and to that of M2-2 bound to 1-chloro-2,4-dinitrobenzene (CDNB). As the

conformation shifts, some regions of the enzyme become more exposed to the

environment resulting in an increased deuterium uptake in that region while areas that

become less exposed see a decrease in deuterium uptake.

33 - Ionic Networks for Controlled Drug Delivery

Olga Yunyaeva1, Tristan Harrison1, Paul J. Ragogna1, Elizabeth R. Gillies1,2

1Department of Chemistry and the Centre for Advanced Materials and Biomaterials

Research (CAMBR), Western University, London, ON, N6A 5B7, Canada., 2Department

of Chemical and Biochemical Engineering, Western University, London, ON, N6A 5B7,

Canada.

In the last 7 decades, controlled drug delivery has seen vast advancements as the field

continues to grow with advancing technology. Hydrogels have shown great promise as

vehicles for drug release due to their ability to swell many times their weight, hold

pharmaceutical agents in their network and release them upon application of a stimulus.

This presentation will focus on exploring ionic hydrogels synthesized from

polyphosphoniums and biocompatible sodium hyaluronate. These networks are held

together by ionic interactions, are capable of being loaded with drugs and releasing them

when exposed to biological salt concentrations. The swelling of these networks was

tested along with the drug loading and release of fluorescein dye as a drug mimic.

34 - Designing Patchy Rod-Like Micelles: Manipulating

Competitive Seeded-Growth Kinetics and Visualizing

Patchiness by Selective Staining

Menandro Cruz1, Jiangping Xu1, Jessica Yu1, Ian Manners2, Mitch Winnik1

1University of Toronto, 2University of Bristol

Rod-like micelles formed by crystallization-driven self-assembly (CDSA) of

poly(ferrocenyldimethylsilane) (PFS)-containing block copolymers (BCP) have been of

interest primarily due to the living nature of micelle growth process. The resulting

micelles are often very uniform in length and morphology. Despite extensive studies of

CDSA by sequential homopolymerization to generate novel block structures, there have

been very few studies of copolymerization by pairs of block copolymers. Here, I describe

a systematic study of co-assembly of PFS-b-polyisoprene (PFS-b-PI) and PFS-b-

poly(dimethylsiloxane) (PFS-b-PDMS), showing that the kinetics of PFS-b-PI is sensitive

to its block ratio. Block copolymer composition can then be utilized to manipulate the

resulting morphologies of rod-like comicelles. In order to characterize the resulting

morphology from competitive co-assembly of PFS-b-PI and PFS-b-PDMS unimers, PI

corona chains have to be stained selectively in order to determine whether the resulting

morphology is patchy or blocky. However, visualization of coronal segregation between

PI and PDMS corona chains of rod-like comicelles made by CDSA has been a challenge

because there is no source of contrast for the polymers when analyzed by transmission

electron microscopy. Here, I show that nanoscale coronal segregation can be visualized

using Karstedt’s catalyst as a source of Pt for staining PI chains through Pt(0)-olefin

coordination. This technique allows selective staining of PI and poly(methylvinylsilane)

(PMVS) corona chains in cylindrical BCP micelles with crystalline PFS core. Identifying

localization of different corona chains of mixed BCP micelles has been of interest in

order to investigate their growth kinetics and subsequently control their degree of

patchiness.

35 - Synthesis of indol-annulated S-containing

polycycles

Mukund Jha1, Spencer Short1, Steven Rhodes1

1Nipissing University

Substituted indoles are among a group of highly sought-after scaffolds because of their

potential of being biologically active. Similarly, polycyclic fused indole moieties are also

of considerable interest as they are often found to be a part of bioactive natural/synthetic

compounds. Hence, developing efficient syntheses of molecules having these structural

motifs are in great demand in the current literature. Unlike indole-fursed pyrans the

chemistry and biological properties of their fused-thiopyran counterparts have not been

explored in greater detail. We have an ongoing interest in the development of novel

strategies to access functionalized indoles. Over the last decade our research group has

demonstrated the synthesis of variety of indole-fused heterocyclic frameworks (e.g

thiopyrano[2,3-b:6,5-b']diindole, thiopyrano[2,3-b]indol-2- one, dihydrothiopyrano[2,3-

b]indole, thiopyrano[2,3-b]indole, benzo[4,5][1,3]thiazino[3,2-a]indole,

dihydroisothiochromeno[3,4-b]indoles and isothiochromeno[1,8,7-bcd]indole) using

indoline-2- thione as a versatile precursor. A brief review of these studies as well as

some recent results will be presented.

36 - Improving phosphoprotein yield from an RNA-

guided genetic code recoding system in Escherichia coli

Malaz Abdelrahim1, Jeremy Thomas Lant2, Patrick O'Donoghue1,2

1Western University, Department of Chemistry, 2Western University, Department of

Chemistry

Expansion of the genetic code beyond the 20 standard amino acids and 64 codons has

been a rapidly growing field on interest. The natural genetic code expansion mechanism

for the twenty first amino acid selenocysteine (Sec) has the ability to recode a codon at

only a specific location of interest, rather than at all instances of that codon as in

previous approaches. This provides a new and selective method to express and

translate phosphoproteins of interest through modifying the existing selenocysteine

translation machinery. Our goal was to engineer the Sec system to produce phosphor-

threonine (pThr)-containing proteins. With the use of RNA-guided recoding, we

established site-directed incorporation of pThr at position 308 in the active site of the

protein kinase B (Akt1). This was accomplished using an engineered mutant of the Sec-

specific elongation factor SelB (SelBSep), and co-expression of a tRNASec mutant.

Modification of an existing protein purification protocol allowed for optimized pThr308

yield and increased phosphorylation was supported by electrophilic separation of

phosphoproteins. Following protein purification, phosphorylated Akt1 production was

confirmed on a Phostag gel by a distinct band shift compared to an unphosphorylated

variant of the protein. The data obtained suggests that pThr was successfully

incorporated in Akt1.

37 - Optimization of an Enantioselective

Desymmetrization of Malonamides via Intramolecular

Buchwald-Hartwig Cross-Coupling Reaction

Jennalee Ramserran1, Dr. Russell Viirre1

1Department of Chemistry and Biology, Ryerson University

The Buchwald-Hartwig reaction is a Pd-catalyzed cross-coupling reaction between an

aryl halide and a nitrogen nucleophile. The Viirre Group has had an interest in exploiting

the use of this reaction to desymmetrize prochiral malonamide compounds via an

enantioselective intramolecular arylation of one the amide nitrogen atoms. Preliminary

work done in the group had achieved moderately good enantioselectivities using

catalysts comprised of a palladium source and a chiral phosphine ligand. In order to

improve upon these results, a pre-catalyst consisting of a palladium complexed with a

non-commercially available chiral phosphine ligand has been prepared. The purpose of

this project was to optimize reaction conditions using this complex to maximize the yield

and enantioselectivity in the malonamide desymmetrization. This presentation will

discuss the results of these studies.

38 - A Comparison and Contrast of Different

Construction Methods of Asymmetric Model Membranes

Brett Rickeard1

1University of Windsor

Plasma membranes (PM) have highly complex structures, including a diverse

assortment of lipid species throughout the lipid bilayer, as well as an asymmetric

configuration between the inner and outer leaflets. However, most cell membrane

research has been studied using symmetric liposomes. This is primarily due to the

difficulty of preparing compositionally accurate asymmetric membranes. In this project,

the structural accuracy and characteristics of current asymmetric model membranes

construction methods were tested using techniques such as small-angle neutron

scattering (SANS), small-angle X-ray scattering (SAXS), and NMR. The specific

asymmetric construction model tested was designed by Dr. Erwin London. Using

London's method, we created asymmetric large unilamellar vesicles (aLUV) via

cyclodextrin mediated exchange. The final vesicles were composed of a POPC/POPG

inner leaflet, and a DPPC outer leaflet. The SANS data showed that the aLUV from the

London's preparation method had little to no structural features. This could be due to the

low yield produced from London's method, or the surplus of protons present in the

vesicle core, causing incoherent scattering. London's method uses a sucrose core for

vesicle separation via density gradient. We investigated the effects of sucrose on aLUV

composition via SANS and SAXS. We found that sucrose lowers the intensity of the

SANS data due to its incoherent scattering qualities. A sucrose core also compromises

vesicle durability and limits the range of viable analytical techniques. Currently, we are

working on fine tuning the solvent suppression on proton NMR for the purposes of

optimizing an NMR based asymmetry assay.

39 - A Biosensor for Au3+ based on a DNAzyme and

Iodide

Lena C.M. Li Chun Fong1, Po-Jung Jimmy Huang1, Juewen Liu1


The traditional role of DNA as merely a chemically inert genetic molecule has been

revised since the discovery of catalytic DNA in 1994. DNAzymes can catalyze various

reactions including RNA-cleavage. However, they are only active in the presence of

metal cofactors which stabilize the highly negative transition state. DNAzyme-based

biosensors exploit this strict requirement for cations. The Ce13d DNAzyme has

previously been reported to detect both lanthanides and thiophilic metal ions. Here, we

aim to develop a highly selective Au3+ biosensor based on Ce13d, which would be

cheaper, faster and more convenient than conventional analytical techniques such as

ICP-MS. The detection system consists of a modified DNA susbstrate strand with a

single ribo-adenine (rA) and scissile sulfur atom. Gel-based assays were performed to

quantify RNA-cleavage which provides an indirect measure of Au3+ concentration. The

addition of I- and EDTA causes a shift of specificity towards Au3+, while all the other

metals were silent under this condition.

40 - Extending π-Conjugation in Boron Difluoride

Formazanates via Sonogashira Coupling

Zachary K. Powell1, Ryan R. Maar1, Joe B. Gilroy1,2

1Department of Chemistry, 2Centre for Advanced Materials and Biomaterials Research

BF2 adducts of chelating N-donor ligands have garnered significant interest amongst

material scientists due to their stability, diverse coordination chemistry and often tunable

light absorption, emission and electrochemical properties. As a result, these compounds

have diverse applications such as in organic solar cells, organic light-emitting diodes and

imaging agents. One such class of compounds that has received much focus are BF2

adducts of formazanates, characterized by a [Ar1 N N=C(R3) N=NAr5]⁻ backbone.1, 2

These compounds can possess extensive π-conjugation – a vital characteristic if a

compound is to be strongly absorbing – and past studies within the group have

demonstrated that extending this conjugation red-shifts their low energy absorption

features. We set out to discover a set of conditions under which BF2 formazanates can

undergo Sonogashira cross-coupling to extend π-conjugation at the Ar1/Ar5 positions of

the formazanate backbone and to ultimately synthesize polymers using these conditions.

While no polymers have yet been synthesized, two new compounds were discovered

that demonstrate the anticipated effects and shed light on potentially competing

reactivity pathways encountered under Sonogashira cross-coupling conditions. During

this presentation, details of the synthesis and characterization of these compounds will

be discussed.

References

1. Maar, R. R.; Barbon, S. M.; Sharma, N.; Groom, H.; Luyt, L. G.; Gilroy, J. B. Chem.

Eur. J. 2015, 21, 15589 15599.

2. Barbon, S. M.; Staroverov, V. N.; Gilroy, J. B. Angew. Chem. Int. Ed. 2017, 56, 8173

8177.

41 - Structural and Mechanical Properties of Palm Oil in

the Presence of dispersed particulates

David Jung-Won Choi1, Derick Rousseau1, Hardeep Devgan1

1Ryerson University

The goal of this research was to assess the role of added sugar (50 wt%), lecithin (0.15

wt%) and aeration on the microstructural, crystallization and mechanical properties of

two types of palm oil over 4 weeks, with the intent being to explore whether the presence

of dispersed sugar, lecithin and air would promote palm fat crystallization. Mixtures were

cooled from 60 to 20°C at 5 °C/min with stirring at 100 rpm in a lab-scale scraped-

surface heat exchanger. Microstructure was examined using confocal microscopy and

polarized light microscopy whereas fat crystal properties were assessed with pulsed

NMR and DSC. Small-deformation rheology examined the evolution in viscoelasticity. In

the absence of sugar, fat crystallization began with the formation of spherulites and

sizable needle-like crystals were observed in the subsequent weeks. There was an

absence of spherulites in the presence of sugar, in conjunction with the reduction of the

needle-like crystal size and thickness. With addition of sugar and aeration, there was a

reduction in enthalpy and a slight increase in solid fat content after the first week in both

palm fats. Addition of sugar also resulted in an increase in the elasticity of both palm

fats, yet both aeration and addition of lecithin reduced elasticity. Once the role of air in

fat-sugar composites are understood, mixtures with a reduced proportion of saturated

fats can be developed.

43 - Discovering the structural stability of CAU-1 and its

properties for CO2 adsorption under extreme pressure

by in situ vibrational spectroscopy

Ryan Park-Lin Ho1, Shan Jiang1, Yang Song1, Yining Huang1


Metal-Organic Frameworks (MOF) are a relatively new hybrid porous material made up

of metal ions and organic linkers that have received lots of attention in recent years due

to its many potential applications such as gas storage and purification, chemical

separation, catalysis, and sensing. In this study, the MOF CAU-1 was examined under

high pressure conditions using a Diamond Anvil Cell (DAC), as an empty framework as

well as loaded with CO2, and the changes could be observed using an Infrared

Spectrometer. Under high pressure, the MOF can undergo interesting structural and

chemical changes that are rarely observed under ambient conditions. CAU-1 was

chosen due to its structure containing large aminoterephthalic acid linker chains whose

amino groups allow for high CO2 adsorption capacity, which makes it a strong candidate

for CO2 storage. The IR spectra of empty CAU-1 under pressure showed an irreversible

phase transition while the CO2 loaded CAU-1 showed marked differences in structural

stability and increasing interactions with CO2 under high pressure. The results from this

study highlight the potential of CAU-1 to be used in greenhouse gas storage and

capture.

44 - Phosphine Michael Addition to Maleimides for

Nanomaterial Modification

Jun-Hyeong Park1, Mark S. Workentin1, Paul J. Ragogna1, Michael A. Kerr1


Nanoscale materials, such as nanoparticles or carbonaceous materials, have been

identified as promising candidates for application in optics, electronics, and biomedicine,

because of their unique structural, mechanical, and optical properties. A key to their

implementation in these applications is the functionalization of the interface of these

materials that adjusts the physical and reactive properties. The thiol-Michael addition

reaction to a maleimide has been an important tool in materials science due to its “click”

nature, which allows for selective and efficient surface functionalization of materials

under mild conditions. Our groups have successfully demonstrated this reactivity on gold

nanoparticles.1,2 Phosphines are often utilized as a catalyst in this type of reaction, but

their use as the primary nucleophile has been underexplored. Such a species could be

advantageous as they can participate in multiple additions to electrophiles.3 The addition

of a variety of phosphines to maleimide will be discussed along with details on

understanding the outcomes of these reactions. Ideally, these benchmark reactions will

deliver functionality to the material (nanoparticle) surfaces.

References:

1. Luo, W.; Gobbo, P.; Gunawardene, P. N.; Workentin, M. S. Langmuir 2017, 33, 1908-

1913.

2. Weissman, M. R.; Winger, K. T.; Ghiassian, S.; Gobbo, P.; Workentin, M. S.

Bioconjug. Chem. 2016, 27, 586-593.

3. Rabiee Kenaree, A.; Berven, B. M.; Ragogna, P. J.; Gilroy, J. B. Chem. Commun.

2014, 50, 10714-10717.

46 - Catalytically Active Silicon Hydride Nanosheets for

CO2 Reduction

Chenxi Qian1, Wei Sun1, Darius Hung1, Dr. Geoffrey Ozin1


Heterogeneous conversion of CO2 to value-added chemicals and fuels by Si surface

hydrides has recently attracted broad research interest. Being earth-abundant, low-cost

and non-toxic, elemental Si is one of the most promising candidates for comprising such

a catalyst, enabling CO2 conversion to synthetic fuels on a giga tonne per year scale. It

is well known however that silicon hydrides react stoichiometrically with CO2 and all

attempts have failed to achieve catalytic conversion of CO2. The problem originates with

the formation of inactive surface silanols and siloxane groups with permanent loss of Si

hydrides. Here, aiming at cracking the core of the problem, we deposited Pd

nanoparticles on the surface of Si nanosheets using an innovative synthetic strategy.

An operando infrared study, with isotope labeling, showed Si hydrides successfully

regenerated on such nano surfaces exposed to CO2 and H2. We demonstrate for the first

time that nanosheets of hydride-capped silicon decorated with Pd nanoparticles can

enable the reverse water gas shift reaction in an unprecedented catalytic cycle.

47 - Exploring Alternative Methods for the Synthesis of

Difunctional Germanes

Curtis Kiteley1


Germanium plays an important role in modern technology in semiconductors and

optical devices. Current processing methods involve the synthesis of GeCl4 from GeO2,

and requires the use of chlorine-based reagents, which pose a risk to both human health

and the environment.1 Recently, an environmentally friendly process for the synthesis of

a GeCl4 substitute, 1, has been developed which avoids the use of chlorine reagents.2

Although tetraorganogermanes can be synthesized from 1 using Grignard reagents, the

synthesis of difunctional germanes using Grignard reagents was not successful. In this

work, the synthesis of difunctional germanes using 1 and organolithium reagents will be

presented.

1 Ullmann’s Encycl. Ind. Chem.; 2000; Vol. 66, 629.

2 Glavinović, et al.; Sci. Adv. 2017, 3, 1.

48 - Insertion of Electrophilic Alkynes into Silylamines

Courtney Dickson1


Abstract: Functionalizing amines is critical for their use in agriculture, pharmaceuticals,

and as fine chemicals. Transition metals have previously been used as catalysts for

such reactions; however, they are often expensive and low in abundance. Due to the

importance of amines, there is a high demand for finding new, more efficient ways to

synthesize them. Low valent main group complexes, such as disilenes are able to

activate ammonia1. The addition of an electrophilic alkyne to the resulting silylamine

results in further functionalization of the amine2. The effects of varying the bulk of the

substituents on the silicon and nitrohen of the silylamine on the alkyne insertion reaction

will be presented.

1Meltzer, A.; Majumdar, M.; White, A. J. P.; Huch, V.; Scheshkewitz, D. Organometallics, 2013, 32, 6844. 2George, T. A.; Lappert, M. F. J. Organomet. Chem., 1968, 14, 327.

50 - Probing Surface Chemistry at the Monolayer Level

with PM-IRRAS

Sydney Legge1, Wilson Luo1, François Lagugné-Labarthet1, Mark Workentin1


Polarization modulation infrared reflection-absorption spectroscopy (PM-IRRAS) is a

powerful technique that provides significantly improved surface sensitivity compared to

traditional infrared vibrational measurements. PM-IRRAS allows one to measure the

infrared spectrum of a monolayer of molecules adsorbed onto a surface while also

providing information about the orientation of molecules in the monolayer. The molecular

organization of surface molecules is a critical parameter that defines surface properties

and reactivity. PM-IRRAS is therefore an ideal technique to study these surface

characteristics. This study focuses on the principles of PM-IRRAS and its applications in

the detection and characterization of self-assembled monolayers (SAMs) of thiol-

containing molecules on gold mirror substrates. In a proof of concept study, PM-IRRAS

is used to determine the orientation of adsorbed 4-nitrothiophenol (4-NTP). This

approach is then used to probe SAMs of a cyclopropenone-masked cyclooctyne capable

of undergoing catalyst-free click chemistry following exposure to ultraviolet (UV) light

(reaction scheme shown). This rapid, bio-orthogonal, and highly chemoselective click

reaction is an incredibly useful tool with a wide variety of applications in synthesis and

surface modification. Overall, this work demonstrates the use of PM-IRRAS across

different fields of chemistry and materials science.

51 - Synthesis of a Fluorogenic Substrate to Monitor

Redox activity in Cystathionine –

Leslie Ventimiglia1, Scott Smith1, Bulent Mutus1


Cystathionine γ – lyase (CSE) is a primary enzyme of the transsulfuration pathway. It is

responsible for degrading sulfur containing amino acids, primarily cystathionine.

Additionally, it is instrumental in producing Hydrogen sulfide (H2S), one of the known

gasotransmitters serving a role in vasodiliation and cell signal transduction. Literature

and previous work done in our lab have elucidated the potential disulfide reducing

capabilities of CSE, a homotetramer containing two CXXC motifs associated with

potential disulfide reduction in each subunit. To characterize the CXXC active site, a

fluorogenic pseudo substrate (FITC-Cys2) was synthesized using cystine, a

hypothesized substrate to CSE to measure enzyme activity using fluorescence. Kinetic

data using the synthesized cystine probe has offered little evidence in favour of cystine

as a substrate to CSE. Despite this, the pseudo-substrate has shown activity with a

known disulfide reducing enzyme, Protein Disulfide Isomerase (PDI). Additional assays

using homocystine, a known disulfide containing substrate to CSE, must be performed to

elucidate the potential high selectivity of its possible disulfide reducing active site.

53 - Conductive Stretchable Fibres for Imperceptible

Electronics

Kathy Nguyen1, Tricia Breen Carmichael1


Electronic textiles (e-textiles) are textiles that incorporate electrical components to impart

electrical functionality, such as conductivity. Truly wearable e-textiles deliver the

electrical functionality while maintaining the softness and stretchability of the textile.

However, creating conductive textiles is a challenge due to the porous structures of

textiles, which consist of an interconnected network of fibers and voids. Current literature

coats textiles with conductive inks that can electrically functionalize textiles, however,

wicking into the fabric’s voids stiffening the textile and diminishes the wearability. To

fabricate truly wearable electronics, it is imperative to find methods that would

functionalize the individual fibres, leaving the voids intact. In this project, we describe a

low-cost, solution-based, electroless nickel-immersion gold (ENIG) process that can be

applied to elastomeric fibres (e.g. Polyurethanes, latex), creating highly conductive and

stretchable gold-coated fibres. These single fibres can then be woven into textiles,

making stretchable, conductive e-textiles. We demonstrate the fibre’s applicability

through different innovative designs. We discuss fabricateing wearable wiring and strain-

sensors by weaving the stretchable conductive fibres through polyester or nylon. This

research provides exciting grounds for design opportunities in the field of wearable

electronics.

54 - Selective molecular receptor for the detection and

removal of mercury ions from solutions.

Alexandra Deckert1, Sarah King1,2, Olena Zenkina1

1University of Ontario Institute of Technology, 2Cardiff University

Trace amounts of heavy metal ions could cause significant harm to biosystems and the

environment. Mercury is well known to be extremely toxic to humans; these metal cause

serious health problems including mental health issues, birth pathologies, and death.

Mercury can exist in three forms: elemental mercury, inorganic mercury, and the most

toxic to humans organic mercury. Current methods for monitoring of metal ions suffer

from high instrumentation cost, spectral interferences, often require destructive sample

pre-treatment, and highly qualified personnel to perform the analysis.2 .This work

investigates mercury detection by exploiting the high affinity of mercury (II) towards the

ligand 4-(2,6-di(thiophen-2-yl)pyridin-4-yl)phenol. This ligand acts as a selective “turn

off” selective fluorimetric sensor for parts per billion to parts per million (ppb to ppm )

levels of mercury. No interference was found in the presence of 19 metal ions including:

Al3+, As3+, Ba2+, Ca2+, Cd2+ Co2+, Cs+, Cu2+, Fe2+, Fe3+, K+, Li+, Mg2+, Na+, Ni2+, Pd2+,

Ru3+, Sn2+, Zn2+. From Job’s fluorimetric titration experiment we were able to define the

metal to ligand stoichiometry as 1:1. This novel mercury complex was characterized via

UV-Visible spectroscopy (UV-Vis) and fluorescence emission spectroscopy. The novel

synthesis of this ligand was investigated and was characterized using 1H, 13C{1H}NMR,

IR, UV-Vis. and fluorescence spectroscopy.

55 - Reactivity Studies of a Stabilized Low-Coordinate

Palladium Complex

David Stephens1, Kyle Jackman1, Johanna Blacquiere1


Copolymers of polar monomers and olefins have beneficial properties that differ from

homopolymers such as improved toughness and adhesion. Transition metal catalyzed

copolymerization suffers from side reactions due to the instability of low-coordinate

catalyst intermediates. Hemilabile ligands can occupy the open coordination site and

improve catalyst performance. The 1-azaallyl moiety can act be hemilabile ligand as it

binds in either a 1-or 2-coordinate fashion and can switch between these modes.

Deprotonating a metal complex with a phosphine-imine ligand yields a complex with a

phosphine 1-azaallyl ligand that has an agostic interaction with one of the methyl groups

on the C-terminus of the 1-azaallyl moiety. Reacting this agostic complex with pyridine

easily affords the pyridine adduct highlighting the reactivity of this complex. The kinetics

of the ligand dissociation was explored for the pyridine adduct by VT NMR experiments.

The dissociation of pyridine is more difficult than interrupting the agostic interaction. This

is reflected in the reactivity of this agostic complex and the pyridine adduct with styrene,

methyl acrylate, and carbon monoxide. The pyridine adduct and agostic complex react

readily with carbon monoxide and produce several products with significant

decomposition regardless of reaction temperature. No detectable reaction was seen with

styrene but methyl acrylate reacted with the agostic complex demonstrating the unique

reactivity of this complex. Additionally, several attempts at copolymerizing styrene and

CO under multiple pressures of CO were made but no copolymerization was seen under

any of the conditions tested.

56 - Nonlinear Phenomena in the Electrochemical

Oxidation of Bisulfite

Fatima Naveed1, Jichang Wang1

1Department of Chemistry and Biochemistry, University of Windsor

Bisulfite has been commonly used as a mild reducing agent in various chemical

industrial productions and food industry. For example, they are used in almost all

commercial wines to prevent oxidation and preserve flavor. In fruit canning, sodium

bisulfite is used to prevent browning and to kill microbes. Understanding the oxidation

kinetics and mechanism of bisulfite is therefore very important to its applications. In this

research, electrochemical oxidation of sodium bisulfite at a Pt electrode was

investigated, in which the absence of oxidants makes the analysis of the oxidation

products easier. Linear sweep voltammetry study illustrates that bisulfite system

compromises of a negative differential resistance (NDR), which is an essential condition

for the occurrence of nonlinear instabilities, observable in the form of spontaneous

oscillations of current at potentiostatic conditions or potential under galvanostatic

conditions. Cyclic voltammetry experiments demonstrate that Pt surface is more reactive

than PtO. Reaction parameters that were systematically explored in this project are

bisulfite concentration and external resistance, where chronoamperometric experiments

carried out at potentials around the bisulfite oxidation peak with a suitable external

resistance lead to observations of significant spontaneous oscillations. Such a transition

may be understood based on the influence of the two parameters on the behavior of

NDR.

57 - Hemilabile NHCs for Oxidation Chemistry with Ni(II)

Hannah Nilsson1, Johanna Blacquiere1


Improving synthetic efficiency of pharmaceuticals and fine chemicals is of great interest

to the scientific community for the environmental and economical benefits it entails.1 This

project works towards the synthesis of an oxidation catalyst that uses abundant,

environmentally friendly O2 as the oxidant. Nickel(II) ligated with an N-heterocyclic

carbene (NHC) ligand has been previously observed to react with O2; the Ni-NHC

oxidizes an allyl ligand to form propenal.2 After aerobic oxidation, previously studied

complexes dimerize and subsequently decompose; eliminating the possibility for the

complex to be catalytic. The theorized mechanism for the allylic oxidation with Ni-NHC

passes through a Ni-OH species. In pursuit of developing an aerobic oxidation catalyst,

we target the synthesis of nickel complexes that react with O2 to make propenal and

form a stabilized Ni-OH intermediate.3 A Ni-NHC complex with a pendant pyridyl group is

synthesized and characterized by variable temperature NMR spectroscopy, UV-Visual

spectroscopy, and mass spectrometry. The hemilabile pyridyl group on new complex is

expected bind nickel after oxidation to increase the coordination number, which is

hypothesized to stabilize the Ni-OH intermediate sterically and electronically. Evidence

supports the synthesis of the target complex and preliminary evidence suggests the

complex reacts with O2.

1. Dach, R.; Song, J.; Roschangar, F.; Samstag, W.; Senanayake, C. Org. Process Res.

Dev. 2012, 16 (11), 1697–1706.

2. Dible, B.; Sigman, S. J. Am. Chem. Soc. 2003, 125 (4), 872–873.

3. Hazlehurst, R.; Hendriks, S.; Boyle, P.; Blacquiere, J. Chemistry Select 2017, 2 (23),

6732–6737.

58 - The Effects of Trivalent Chromium on Human

Bladder Cancer Cells Probed by Scanning

Electrochemical Microscopy

Jonthan Wong1, Fraser Filice1, Lina Yao1, Zhifeng Ding1


Our work has demonstrated the detrimental effects of dichromate on the cell’s behaviour

and functions [FP Filice, MSM Li, JM Wong, ZF Ding, J. Inorg. Biochem. 2018,

DOI:10.1016/j.jinorgbio.2018.02.009]. In contrast, trivalent chromium (Cr(III)) is essential

in trace amounts and serves many biological roles. Cr(III) notably acts as a regulator in

the insulin pathways. In this thesis work, by subjecting single T24 human bladder cancer

cells to increased concentrations of Cr(III), we explore the toxicity of the essential metal

in a long duration study. Scanning Electrochemical Microscopy (SECM) is a non-

invasive analytical technique that is utilized to characterize interfacial chemical activity

and obtain topographical images. By monitoring the electrochemical current feedback at

an ultramicroelectrode approaching to a live T24 cell, we can track external redox active

mediating species or reactive oxygen species generated from the cell. SECM is

therefore an optimal candidate to probe the physiological behaviour of single cells.

Coupling with a finite element analysis model, COMSOL Multiphysics software, a

simulated current response can be obtained and used to quantify the permeability of the

cell under given stress conditions by Cr(III). The toxicity of Cr(III) is further explored

using a MTT viability study, to gain insight into the correlation of cell permeability to

viability. These quantified features will shed light onto the possible cell process such as

lipid peroxidation that is occurring as the cell is subjected to the external stress. These

exciting results further demonstrate the versatility and power of SECM as a bioanalytical

technique to probe cell physiology.

59 - Gold Nanoclusters and Their Complexes:

Experimental and Computational Studies

An Le1, Ian Hamilton1, Vladimir Kitaev1

1Wilfrid Laurier University

Gold nanoparticles have attracted attention in recent years because of their unique

properties which can differ significantly from those of the bulk metal. Gold nanoparticles

can be chiral giving them extended functionalities. Due to their organic shell, monolayer-

protected AuNPs in general can be dissolved in various solvents and are amenable to

chiroptical techniques such as electronic circular dichroism. Density functional theory

(DFT) is a computational quantum mechanical modelling method and is the backbone of

electronic structure calculations. Used primarily for the modelling and simulation of

chemical many-body systems, DFT solves the Schrӧdinger equation for an interacting

system by mapping it exactly to a much simpler non-interacting system. Both

experimentally and computationally, Aun complexes with n = 20-22, have remained

ambiguous over the past decade. The Au20 tetrahedral structure is known to be

extremely stable. Computational studies of Aun(SR)m where R is a functional group such

as –H or –CH3 are entirely feasible. Experimentally, the peak at ~ 500 nm was observed

in all of the absorbance spectra. This could be a gold plasmon peak. This interference

lowers the chances of obtaining evidence for the desired Aun complexes. Since gold

nanoparticle complexes have many applications in nanomedicine and chiral gold

nanoparticle complexes could provide additional functionality in nanostructured devices,

it is crucial to do more work in this area.

63 - Effects of Metacognitive Practices on Introductory

Organic Chemistry Students. A Closer Look at Learning

Task Inventories

Tarique Plummer1, Stephen L. MacNeil1, Eileen Wood1


Organic Chemistry students generally find the course to be quite demanding. The

challenge of educators is to assist the students in being cognitively critical, reflective as

well as targeted in their studying modus operandi. One way of doing this is to teach

students about metacognition, an awareness and understanding of one’s own thought

processes, and provide opportunities for students to practice metacognitive strategies.

We have been engaged in a research program that measures the effects of

metacognitive activities on introductory organic chemistry students’ self-reported

metacognitive skills and performance. One of these metacognitive activities, Learning

Task Inventories (LTIs), asks students to (1) indicate, on a chapter-per-chapter basis,

the learning tasks they think they can perform after having been exposed to chapter

resources, (2) complete a short multiple choice quiz pertaining to a subset of these

learning tasks and (3) respond to a short survey on the usefulness of the LTIs. This

presentation will describe the effects of LTIs on students’ self-reported metacognitive

skills and performance. The experimental design encompassed 259 students enrolled in

an Organic Chemistry I course during the fall term of 2015 who completed introductory

and end-of-term surveys, including a Metacognitive Awareness Inventory (MAI), and 8

weekly LTIs, among other metacognitive activities, over the term. Responses were

analyzed using Statistical Package for the Social Science (SPSS).

65 - Synthesis of New Phosphorus-containing

Functional Groups Using 2-Phosphaethynolate Anion

Kevin M. Szkop1, Dr. Andrew R. Jupp1, Hlib Razumkov1, Prof. Dr. Douglas W. Stephan1


Main group analogues of organic functional groups have always attracted inorganic

chemists. In the last 5 years, new synthetic strategies for phosphorus-containing starting

materials has led to a renewed interest in the field. In particular, an improved synthesis

of sodium 2-phosphoethynolate, [Na(diox)3][PCO] gives access to a reagent useful in the

formation of novel phosphorous-containing compounds. In this study, nucleophilic

addition of phosphides to triphenylgermylphosphaketene, derived from [Na(diox)3][PCO],

yields crystalline anionic diphosphaureas in high yields. Notably, the negative charge

shows appreciable delocalization on the anionic PCO fragment. Subsequent electrophile

addition resulted in formation of a range of substituted diphosphoureas or

phosphanylidenes, with O- or P- preference depending on the electrophile. Included in

these products is a stable and crystalline benzyl-substituted diphosphourea, the first

compound of this type to be studied crystallographically. The synthesis, properties,

relevance and future directions of these rare reagents will be discussed.

67 - Increasing Stretchability of Conjugated Polymers

Using Metal-Ligand Coordination

Kacper Wojtkiewicz1, Simon Rondeau-Gagne1


Stretchable and mechanically robust materials are now becoming crucial for the

development of wearable electronics. In particular, semiconducting conjugated polymers

have been shown to be remarkable candidates when preparing new electronic devices

as the exhibit good charge transport properties, synthetic versatility and easy tunability.

In recent years, the development of these types of materials have been utilized the use

of dynamic crosslinking, especially metal-ligand interactions, is a promising avenue to

prepare and design stretchable materials while also enabling novel properties such as

self-healing. However, in their synthesis and application, there are many challenges

overcome to achieve stretchable conjugated polymers, due to the intrinsic competition

between electronic and mechanical properties.

The objective of the project is to develop a novel strategy towards developing

intrinsically stretchable and self-healing conjugated polymers for application in

stretchable electronics. This main objective will be achieved by incorporating metal

coordinating moieties, namely imine side-chains, to the polymer in order to chelate to

Iron(II). This dynamic coordination will allow for the polymer network to dissipate strain,

thus enhancing the mechanical properties of the materials. Moreover, this will also allow

for regeneration of the polymer network after being damaged through a process known

as self-healing. This presentation will discuss our recent progress toward new metal-

coordinating conjugated polymers, especially focusing on their design and preparation.

68 - Discovering Frustrated Lewis Pairs Through

Phosphenium Cations

Maxemilian Nascimento1, Charles L.B. Macdonald1


The activation of small molecules has been a large area of interest but this process

has typically been done using expensive transition metal catalysts. In recent years it has

been shown to be viable through the use of Frustrated Lewis Pairs (FLPs), which do not

contain any transition metals.1 FLPs often consist of a borane as a Lewis acid and a

phosphine as a Lewis base but there have been no reports of phosphenium ions acting

as the Lewis acid in an FLP.2 The topic of discussion will be exploring N-Heterocyclic

Phosphenium ions (NHPs) as Lewis acids in an FLP system, including both

intramolecular as well as intermolecular FLP designs.

(1) Stephan, D. W. Org. Biomol. Chem. 2008, 6 (9), 1535.

(2) Weicker, S. A.; Stephan, D. W. Bull. Chem. Soc. Jpn. 2015, 88 (8), 1003–1016.

70 - Utilization of Pincer Ligands in Main Group

Chemistry

Blake St. Onge1, Ala'aeddeen Swidan1, Charles L.B. Macdonald1


The utilization of pincer ligands in organometallic chemistry offers different modes of

reactivity of metals, allowing for unique catalytic reactivity and application. Pincer ligands

have not been exploited to the same extent with main group elements. Utilizing concepts

established in transition metal chemistry, we are investigating new pincer complexes

with potential of harnessing reactive main group centers.1 The presentation will consist

of the complexation of various group 13-15 main group elements into bis((1H-

benzo[d]imidazol-2-yl)methyl)amine (with group 15), and 2,6-bis(1-(3,5-

bis(trifluoromethyl)benzyl)-1H-benzo[d]imidazol-2-yl)pyridine (with groups 13 and 14). X-

ray structures, results and reactivity will be detailed.

(1) Dunn, N. L.; Ha, M.; Radosevich, A. T. Main Group Redox Catalysis: Reversible P

III/P V Redox Cycling at a Phosphorus Platform. J. Am. Chem. Soc. 2012, 134 (28),

11330–11333.

72 - Bright electrochemiluminescence from carbon

quantum dots at low costs

Malin Ly1, Shuijian He1, Liuqing Yang1, Ruizhong Zhang1, Jonathan R. Adsetts1, Zhifeng

Ding1


Electrochemiluminescence (ECL) is a light emitting process resulting from the

interactions between electrogenerated radical species. The smart combination of

electrochemistry and chemiluminescence gives ECL the controllable properties over light

emission by simply adjusting the electrode potentials and reactant concentrations. ECL

has now become a powerful and widely used technique in the fields of light-emitting

devices and immunoassays. For an economical and environmental friendly luminescent

material in the above applications, carbon quantum dots (CQDs) were successfully

synthesized using folic acid as a starting substance via one-pot pyrolysis. The obtained

CQDs were characterized using photoluminescence (PL) spectroscopy. It was

discovered that our CQDs exhibit blue luminescence with maximum excitation and

emission wavelengths at 355 and 440 nm, respectively. The luminescence quantum

yield was determined to be 5.4% relative to quinine sulfate. ECL of the CQDs was very

strong in the presence of K2S2O8 as a coreactant and an ECL efficiency of 12.5%

relative to the Ru(bpy)3Cl2/K2S2O8 coreactant system was reached. The spooling ECL

spectra revealed a potential-dependent emission. The ECL emission peak wavelength of

the above coreactant system was determined to be 700 nm, which is 260 nm red shifted

when compared with its maximum fluorescence emission. This significant difference

between ECL and PL peak wavelengths may ascribe to their different emission

mechanisms: the ECL emission came from the surface states while the PL emission was

from the core states of CQDs. With such excellent photoluminescence and

electrochemiluminescence performances, stable and low-cost CQDs are anticipated for

light emitting electrochemical cells and immunoassays.

76 - Analysis of the Binding of Bifunctional Aptamers

using Isothermal Titration Calorimetry (ITC)

Ruqaiya Qureshi1, Philip E Johnson1

1York University

In recent years, DNA aptamers have become of increasing importance due to their great

potential in biosensing applications, nanowire assemblies and drug design in

pharmaceutical industries. Therefore, in order to explore the binding affinity and

behaviour of the aptamers, ITC was performed using the aptamers and ligands under a

constant set of conditions. All the experiments were carried out at 15 C, in 20 mM Tris,

140 mM NaCl and 5 mM KCl. We are interested in fusing two aptamers together to form

bifunctional aptamers consisting of two binding sites, to analyze their binding behaviour

with ligands. We have chosen to study the cocaine-binding and DCA- binding aptamers,

as shown in Figure 1. Therefore, when the ligands were titrated with the aptamer

solutions, DCA and cocaine were found to bind the DCA binding site and cocaine

binding sites respectively, in an independent manner. Additionally, we will present the

dissociation constants associated with bindings at each of the two sites for the

bifunctional aptamers and discuss the thermodynamic parameters of each binding event.

All these results help make connections between the binding behaviour and the structure

of the aptamers.

78 - Enzyme-powered Three-Dimensional DNA Walking

Device for Discriminating Single Nucleotide Variants

Yongya 1

1Brock Uinversity

Single nucleotide variants (SNVs) are important both clinically and biologically, because

single base differences in nucleic acid sequences can have profound biological

consequences. Herein, we engineered a nicking endonuclease-powered three-

dimensional (3D) DNA walking device that discriminates SNVs with both high sensitivity

and high specificity at low target concentrations. Particularly, we introduced a new in-

solution tuning method that harnesses a single fuel molecule to regulate the

thermodynamic gain of the 3D walking device via noncovalent DNA catalysis. Our device

produced discrimination factors that are comparable with commonly used molecular

probes (e.g., molecular beacons and strand displacement beacons) but improved the

assay sensitivity by ~100 times. Our results also demonstrate that rationally designed

DNA catalysis can be used to quantitatively improve the molecular devices with high

structural and functional complexity.

80 - Effect of Electrolyte Composition on Plasma

Electrolytic Oxidation Coatings on AM60 Magnesium

Alloy

Mandy Le1, David Shoesmith1, Vahid Dehnavi1, Jamie Noel1


In the biomedical industry, there exists a strong interest in the use of Magnesium (Mg)

alloys as biodegradable implant materials due to their intrinsic biocompatibility and great

mechanical properties. However, Mg alloys have a high rate of degradation in the

physiological environment and low wear resistance. Therefore, implants composed of

Mg alloys may lose their mechanical integrity before the completion of the healing

process. Surface treatment is the general approach to overcome these deficiencies.

Several treatments have been developed, among which plasma electrolytic oxidation

(PEO) has proved promising results. PEO is a new electrochemical surface treatment for

some metals to enhance their corrosion and wear resistance. Electrolyte composition

and electrical parameters during deposition play a vital role in the formation of PEO

coatings and in determining their properties. To investigate the effect of electrolyte

composition on coating morphology and corrosion properties, electrolyte solutions

containing different concentrations of sodium metasilicate, potassium hydroxide and

triphosphate decahydrate were prepared, and samples were coated at three current

densities. The morphology, chemical composition and microstructure of the coatings

were analyzed using scanning electron microscopy (SEM) and energy dispersive X-ray

spectroscopy (EDX). Phase compositions of the coatings were determined with X-ray

diffraction (XRD) and electrochemical tests were carried out to study the corrosion

properties of PEO coatings. The results suggest that changing the composition of the

electrolyte affects coating growth behaviour, surface morphology, and corrosion

resistance. The outcomes from this research help us choose electrolyte compositions

that result in coatings with improved properties for different applications.

81 - Alumina Sol Gel and Polydimethylsiloxane

Composite Interlayers for Increased Stretchability in

Deformable Electronic Devices

Calum Noade1, Tricia Breen Carmichael1


In the field of stretchable and bendable electronics, there exists a myriad of different

approaches to developing such devices. Some researchers have opted to use inherently

conductive polymers such as PEDOT:PSS, while others use thin films incorporating

silver nanowires, carbon nanotubes, and other conductive films. Of the various methods

to impart conductivity to an elastomer, a metal layer such as gold is the most conductive

initially (i.e. before stretching). Gold is not intrinsically stretchable, and when deposited

on an elastomer such as poly(dimethylsiloxane) (PDMS) and stretched, it will relieve

strain by forming channel cracks perpendicular to the vector associated with stretching,

rendering the sample non-conductive at approximately 10-20% elongation. New

research aims to relieve this strain of stretching by using a roughened, adhesive

interlayer which employs a composite of alumina sol gel and PDMS, deposited on a

PDMS substrate followed by gold deposition. The roughened surface causes a

localization of strain at particular points on the interlayer in order to interrupt channel

cracks and maintain conductivity upon stretching. A condensed, amorphous sol gel has

not previously been used to impart roughness to an elastomer substrate in the

development of deformable electronics. Initial testing suggests that this interlayer can be

used effectively to fabricate deformable electronic devices which will experience a

minimal increase in resistance upon elongation.

82 - NMR and Electrochemical Analysis of Bovine

Cytochrome b5 G62 Deletion Mutant

Rebecca Schalike1

1Trent University

Cytochromes b5 (CYTB5s) are small electron-transfer heme-proteins that are

widespread among eukaryotes. The structure of CYTB5 has been determined in a

variety of species, and a highly conserved protein fold has been identified. The heme

cofactor is coordinated two axial histidine ligands, H39 and H63. In certain species, the

imidazole rings of these ligands have a perpendicular conformation, while in others, such

as the well-studied bovine CYBT5, the imidazole rings are coplanar. To determine

whether this structural difference was related to a difference in residue spacing between

the coordinating histidines, we prepared a bovine CYTB5 variant (DG62) in which

glycine-62 was was deleted. While DG62 retains the coordination geometry of wild type

protein, my research aims to study other possible effects on the heme environment

through the use of 1-D 1H-NMR spectroscopy and on the reduction potential of the

protein by cyclic voltammetry (respectively). NMR experiments comparing wild type and

DG62 in the upfield (-1 to -8 ppm) and downfield (10 - 30 ppm) permitted assignment of

several peaks originating from the peripheral groups of the heme cofactor and indicate

differences in the local heme environment. Electrochemical experiments are in progress

and the results of these will also be presented.

83 - MS in probing protein-small molecule interaction

Elida Bani1

1York University

Alpha-synuclein is associated with Parkinson Disease, and it tends to aggregate when

overexpressed or mutated typically at the N-terminal domain. There are evidence that

the aggregates are toxic to neurons. Thus, preventing monomers to aggregate or

dissociating oligomers could stop PD from progressing. Here we demonstrate the use of

TRESI-HDX Quadrupole coupled with Time Of Fly Mass Spectrometer to probe the

interaction of small molecules with alpha-synuclein as a monomer and an oligomer. The

findings indicate that none of the small molecules interact with monomeric alpha-

synuclein. However, the EGCG show to protect the peptide 114-124 of the C-terminal

domain of oligomeric alpha-synuclein. Ultimately, since EGCG shows interaction with

oligomers by dissociating them and no interaction with monomers, it has been

suggested that oligomers and monomers of alpha-synuclein possess different properties

from each other.

84 - Optimized synthesis of pyridine-based porphyrins

for comparative homogeneous electrocatalytic

reduction of CO2

Billy Deng1, Maryam abdinejad1, Caitlin Dao1, Xiao-an Zhang*1, Bernie Kraatz1


The conversion of carbon dioxide (CO2) into fuels has been a focal point in

contemporary research aiming to tackle the issue of climate change. However, reducing

the CO2 into usable compounds such as methanol is a challenge due to the high

thermodynamic and kinetic stability partially attributed to the linear structure of CO2.

Pyridine (Py) and pyridine derivatives have been shown as efficient electrocatalysts for

stepwise CO2 reduction to methanol by serial proton-coupled electron transfers, but are

noted for their low stability and current densities.

Here, we have designed and optimized the synthesis of different symmetrical and

nonsymmetrical pyridine porphyrin (Pyp) isomers, which are very stable catalysts due to

the unique porphyrin structure. We will also compare the electrochemical behaviors

between Pyp isomers in terms of CO2 reduction using Cyclic Voltammetry (CV). The

impact of conjugation on redox efficiency will be assessed.

85 - Alignment of multi-walled carbon nanotubes on a

silicon substrate using an alignment relay technique

Iris Chan1, Monika Kulak1, Derek Schipper1


A novel method was recently developed by the Schipper group at the University of

Waterloo to address both the sorting and alignment of single-walled carbon nanotubes

(SWNTs) for applications in nanoelectronic devices. This procedure employs an

alignment relay technique (ART) where information is passed from a liquid crystal

medium to small organic molecules to form an aligned, functionalized surface for

nanotube deposition.1 This technique has successfully sorted and aligned SWNTs

simultaneously. Additional advantages of the method include operationally simplicity,

compatibility with common substrates under benchtop conditions, and lack of necessity

for specialized instruments. The work discussed here application of the ART to multi-

walled carbon nanotubes (MWNTs) to further expand on the applicabilities of the

method. Optimization of the technique for MWNTs was done by adjusting deposition

time, concentration, and ionic surfactant, in addition to exploring the effects of

sonochemical treatment on the degree of alignment. It was observed that the alignment

technique is preferential for a certain size of MWNTs, and specific sonication

conditions improved tube alignment. Thus, using the ART with sonochemical treatment

to produce aligned MWNT surfaces may potentially be useful in improving the

mechanical reinforcement and electrical conductivity of nanotube-composite materials.

(1) S. Selmani, D. J. Schipper, Angew. Chem. 2018, 130, 2423.

86 - Ratiometric Fluorescent Chemosensing

Carboxylesterase 2 Activity

Karishma Kailass1, Andrew Beharry1


Fluorescent probes are powerful tools to monitor enzymatic activity in live cells with high

spatial and temporal resolution. In particular, ratiometric probes (i.e. fluorescence at

different wavelengths) can provide accurate analysis by internal referencing.

Carboxylesterase 2 (CES2) is the major human carboxylesterase isozyme that is

overexpressed in tumour tissues, and thus serving as an excellent target for cancer

diagnosis. To this regard, we designed and synthesized a series of ratiometric

fluorescent probes, which produces large fluorescent responses in two emission

channels (yellow and orange) in the presence of CES2. This presentation will discuss

the characterization of these probes and their ability to detect and monitor CES2 activity

in vitro and in live cells.

88 - A Study of the Fluorescent Properties of Rhenium -

Naphthalimide Conjugates

Mariel Bulcan-Gnirss1, William Turnbull1, Emily Murrell1, Leonard G. Luyt1,2,3

1University of Western Ontario, 2London Regional Cancer Program, 3Lawson Health

Research Institute

1,8-Naphthalimides have been employed as cellular imaging agents due to their

fluorescent properties. The functionalization of an amino group to the 4th position of the

naphthalimide ring system creates a complex that has absorption in the visible region of

the electromagnetic spectrum, with a large Stokes shift. Langdon-Jones et al. reported

on 4-amino-1,8-naphthalimides containing a di-picolylamine binding unit to chelate Re(I).

Coordination was found to increase fluorescence lifetimes and inhibit quenching

pathways, thus improving the quantum yields. Since Re is often used as a non-

radioactive analogue of 99mTc, the most commonly used radioisotope for single photon

emission tomography (SPECT) imaging, bioconjugates of these Re/99mTc labeled

naphthalimides could be employed as dual modality fluorescence/ SPECT imaging

agents. In this work, the fluorescence properties of the metal complexes were studied by

altering the net charge of the chelation system. Three 4-amino 1,8-naphthalimide

analogues were synthesized, consisting of tridentate chelators conjugated to the

naphthalimide scaffold. Coordination with Re(I) tricarbonyl resulted in metal complexes

with charges ranging from -1 to +1. The absorbance maximum of the negative to the

positive species was seen to shift bathochromically when the charge state of the Re

complex changed from negative (429nm), to neutral (425nm), to positive (423nm). To

investigate differences in fluorescent properties, fluorimetry was used to determine the

quantum yields of all species synthesized. The findings from this study will assist in

designing future metal-based naphthalimide molecular imaging agents.

90 - The Analysis of Carbene-Stabilized Phosphorus(I)

Cations

Charles L. B. Macdonald1, Louae Abdulla1, Justin F. Binder1


The chemistry of low-oxidation state main group elements has been an area of

growing interest over the last century.1 Phosphorus(I) containing molecules have only

been lightly studied since their introduction to the inorganic world.2 A new, convenient,

and tuneable method for synthesizing NHC-stabilized phosphorus(I) cations has been

developed by our group using a previously reported triphosphenium reagent and N-

heterocyclic carbenes (NHCs).3 The synthesis and spectroscopic characterization of a

sterically encumbered derivative will be discussed, along with studies into its reactivity

towards various substrates.

(1) Chivers, T.; Konu, J. THE FUTURE OF MAIN GROUP CHEMISTRY.

Comments Inorg. Chem. 2009, 30 (5–6), 131–176.

(2) Dimroth, K.; Hoffmann, P. Phosphacyanines, a New Class of Compounds

Containing Trivalent Phosphorus. Angew. Chem. Int. Ed. 1964, 3 (5), 384–384.

(3) Kosnik, S. C.; Binder, J. F.; Nascimento, M. C.; Macdonald, C. L. B. Preparation

and Reactivity of a Triphosphenium Bromide Salt: A Convenient and Stable Source of

Phosphorus(I). J. Vis. Exp. 2016, No. 117.

91 - Synthesis of small molecule biological antifreezes

and applications in cryopreservation

Greg Yousif3, Seyed Iraj Sadraei1, John. F Trant2

1PhD graduate student mentor, 2Supervisor, 3Presenting Author

Certain organisms have evolved carbohydrates that act as antifreezes, antifreeze

glycoproteins (AFGPs), helping to survive sub-zero environments. The biological

antifreezes act through two different mechanisms: thermal hysteresis (TH) which is the

selective depression of the freezing point without changing the melting point of water

(this prevents the formation of ice crystals in the hysteretic gap); and ice recrystallization

inhibition (IRI), where the compounds prevent the growth of large crystals at the expense

of small crystals during the thawing process. Natural AFGPs show IRI activity, and this

could be useful for the cryopreservation of organs and tissue; however, they also have

potent TH activity that leads to damage during freezing. These two effects must be

decoupled in any useful cryopreservative, otherwise organs will be damaged as they are

frozen. We have made small molecule glycolipids, far simpler analogues of the

glycopeptides that have been shown to exhibit equipotent IRI activity as the AFGPs, but

do not exhibit TH activity. These materials are being used by our collaborators to

cryopreserve mammalian cells. Many different diseases and terminal conditions cannot

be cured unless through organ replacement. The eventual goal of this project is to

develop a means by which whole organs can be stored for longer durations of time

allowing for increased chance of survival for people faced with debilitating health

circumstances. In this presentation, the theory underlying biological antifreezes and their

potential for applications in biomedicine, the synthesis of our materials, and the

cryopreservative data related to our systems will be discussed.

92 - Inert-Bond Activation Using a Pentanuclear Nickel

Hydride Cluster

Matthew McLaughlin1, Manar M. Shoshani1, Samuel A. Johnson1


The activation of inert-bonds, such as C-C, C-H, and C-O bonds, in cheap and abundant

chemical feedstocks provides a hypothetical alternate route to essential chemicals and

fuels. By developing cost-efficient catalysis for these difficult bond transformations,

presently unusable materials could become future feedstocks. The pentanuclear nickel

hydride cluster, [(iPr3P)Ni]5H6 (1), has recently demonstrated the ability to activate

typically inert-bonds under mild conditions due to cooperative reactivity between the five

Ni centres, reminiscent of surface catalysis. Studies into the mechanisms of inert-bond

activation by 1 are underway, in the hopes of better understanding how these species

dismantle and remake typically inert bonds under mild conditions, with the potential to

discover new reactivity. In previous work, it has been suggested that [(iPr3P)Ni]5H4 (2) is

the reactive intermediate in bond activation. The current goal is to develop a synthetic

route to species 2, which is likely highly reactive, and study its interactions and reactivity

with inert-bond containing substrates.

The proposed intermediate, 2, has been observed using proton NMR at low temperature

when one equivalent of isobutylene is exposed to 1. Since the suggested intermediate 2

has been observed while in the presence of 1, we propose that it is possible to produce

2 by abstracting a hydride from 1 using trityl tetrakis[3,5-bis(trifluoromethyl)-

phenyl]borate, followed by a mild base to remove the remaining proton. Initial attempts

to abstract a hydride from 1 resulted in the paramagnetic intermediate [(iPr3P)Ni]5H6+ (3),

and attempts to transform 3 into the proposed intermediate 2 are currently underway.

93 - Investigation on the Contribution of Electronic

Effect of Mn-Porphyrin-Based MRI Contrast Agents on

T1 Relaxivity

Lida Tan1

1University of Toronto Scarborough

Magnetic resonance imaging(MRI) is a non-invasive diagnostic technique that allows the

visualization of abnormal tissues. The distinction between diseased and healthy tissues

may require contrast agents to improve sensitivity and enhance tissue

contrast. Gadolinium-based contrast agents(GBCAs) are commonly used in MRI

diagnosis, which have several drawbacks including in-vivo toxicity upon Gd-dissociation

and decreased sensitivity (measured as r1) at high magnetic fields. Manganese(III)

porphyrins have proven to be a potential alternative to GBCAs due to a better

biocompatibility over Gd and a significantly high r1 at clinically relevant fields. The

challenge remains in improving the sensitivity of these compounds. We attempt to

optimize r1 based on the Solomon-Bloembergen-Morgan model. The r1 depends on

several intrinsic factors, of most relevance to this project the electron spin relaxation

time(te). Other important factors such as water exchange(tM) and rotational correlation

time(tR) and their effects on r1 have been studied previously, however, the effect of

electron charge transfers between ligand and metal on r1 remains under investigation. It

is hypothesized that the increase in spin-delocalization and electron density facilitated by

adjacent functional group would favorably affect r1 at relevant fields. Here we

synthesized porphyrin derivatives with a strongly withdrawing nitro group and electron

donating amino group directly linked to the meso position. The successful synthesis of

the products was characterized by 1HNMR, ESI-MS, HPLC, and UV-vis when applicable.

Both derivatives showed significant spectral differences compared to previously

synthesized porphyrins in our lab. We are currently working on building the NMRD

profile to convince our hypothesis.

96 - Diastereoselective Preparation of Chiral Amino

Sulfoxides Through Sulfenate Chemistry

Priya Pal1, Adrian Schwan1, Erwin Remigio1

1University of Guelph

The oxidation of sulfides play an important role in organic chemistry since sulfones and

sulfoxides are found in many natural, pharmaceutical, and agricultural compounds.1

Sulfenate anions are the conjugate base of sulfenic acids and are synthesized in situ as

a reactive intermediate.2 The prochiral nature of the sulfenate allows for the investigation

of stereoselective alkylation reactivity of aryl and alkyl sulfenates.

The S-alkylation of the sulfenate anion leads to a chiral sulfoxide that can induce chirality

in other reactions.3 Such chiral sulfoxides provide assistance in asymmetric synthesis

and chiral drug synthesis. Asymmetric synthesis reactions have chiral elements that are

formed, which produces unequal amounts of diastereomeric products. This type of

selectivity is profoundly important in chemical and pharmaceutical industries and chiral

sulfur compounds can be used in the production of amino acids.4 In this study,

sulfenates are generated to create chiral sulfoxides using coordinating N-groups. The R

group used in my synthesis was anthracene and the N-group electrophile used was (S)-

N-Boc-2-amino-3-phenylpropyl iodide. The synthesis investigated was derived from

previous work performed by the Schwan group with chiral sulfoxides. The goal of

increased yields and diastereoselectivity was pursued.

1. Fukuda, N.; Ikemoto, T. J. Org. Chem. 2010, 75, 4629–4631.

2. Singh, S. P.; O’Donnell, J. S.; Schwan, A. L. Org. Biomol. Chem. 2010, 8, 1712–1717.

3. Söderman, S. C.; Schwan, A. L. J. Org. Chem. 2013, 78, 1638–1649.

4. Matsui, T.; Dekishima, Y.; Ueda, M. Appl. Microbiol. Biotechnol. 2014, 98, 7699–7706.

97 - Liquid Chromatography- Tandem Mass

Spectroscopy Method Validation and Analysis of

Trichothecenes in Agriculturally Relevant Wheat

Samples

Emily Maloney1,2

1Agriculture and Agri-Foods Canada, 2University of Western Ontario

An efficient method for regulation was developed to monitor the mycotoxins produced by

Fusarium graminearum. The variable geographical factors and the inherent risk to

human and animal health warrants the need for a simple, quantitative method for

regulation purposes.

Previous attempts at complete separation were unsuccessful due to the structural and

behavioural similarities of the trichothecene family. The newly determined HPLC-MS/MS

method monitors the presence and quantities of deoxynivalenol, 3-acetyldeoxynivalenol,

15acetyldeoxynivalenol, deoxynivalenol-B-glucoside, NX-2, NX-3, Sambuconal, Aflatoxin

G1, Aflatoxin B1, Diacetoxyscop, OTA, Xearleone and Sterigmatocystin.

Chromatographic multi-separation was achieved using Agilent C18 Eclipse 2.1x100mm

solid phase and acetonitrile with 0.1% formic acid and water mobile phases. With

specific focus on DON, 15-ADON, 3-ADON and the NX toxins a standardized sample

preparation method was used with five commercially available grain including durum,

whole wheat, red wheat, 12 grain and whole wheat flour. Method accuracy was verified

by analyzing certified reference material and resulted in levels higher than allowed by

Canadian regulations.

98 - Characterization of a unusual transcription factor in

the protist, Giardia intestinalis

Jessica Chorolovski1, Ally Yang2, Timothy Hughes2, Janet Yee1

1Biochemistry and Molecular Biology Program, Trent University, 2Department of

Molecular Genetics, University of Toronto

The TATA-binding protein (TBP) is one of the most studied eukaryotic transcription

factors due to its importance in the transcription by all three RNA polymerases. The

TBP in Giardia intestinalis, a common protozoan contaminant of freshwater, is one of the

most divergent of the TBPs known to date. The Giardia TBP has substitutions in 3 out of

4 critical phenylalanine residues that contribute to the "kink" induced in the DNA

sequence when TBP binds to the TATA-box in other eukaryotes. Moreover, canonical

TATA-boxes with a consensus sequence TATA(A/T)A(A/T)(A/G) appear to be absent in

the majority of Giardia gene promoters. These observations led us to question the DNA-

binding specificity of the Giardia TBP (gTBP) and its role in transcription

regulation. Previous studies in our laboratory showed that gTBP does not bind TATA or

TATA-like sequences but binds selectively to only a few of the Giardia gene promoters

that were tested. To further explore the DNA sequence recognized by gTBP, I used a

high throughput method where the binding preference of gTBP is examined for all

possible 8 nucleotide DNA sequences. Intriguingly, a sequence motif consisting of

AGGGGC was identified to be the highest ranked recognition sequence from this

analysis. The verification of this result and its significance will be discussed.

99 - Synthesis of Novel Benzosiloles as

Electrochemiluminescent chromophores

Donghyun Koo1, Tyler Day1, Brian Pagenkopf1


Thienyl appended siloles are excellent and novel materials for chemosensors, electro-

current chromophores and light emitting diode applications. Siloles with thienyl

substituents at C2 and C5 show enhanced the luminescence properties.

Benzosiloles, as aryl fused silole derivatives, are alternative molecules which are more

readily synthesized. A recent preparation of benzosiloles developed by the Chatani

group using the rhodium catalyst ([RhCl(cod)]2), combined with the Pagenkopf group's

knowledge of thienyl-siloles, new thienyl-benzosiloles has been designed and

synthesized. The synthesis employs the cycloaddition of 2-silylphenylborates and

thienyl-acetylenes catalyzed by a well-defined rhodium catalyst. Novel thienyl-

benzosiloles with different thiophene chain lenghts have been synthesized, and their

electrogenerated chemiluminescence (ECL) is being investigated.

100 - Synthesis and characterization of high-swelling

hydrogels of Polyacrylamide and Polyvinylpyrrolidone

cross-linked with N-methylenebisacrylamide

Celia Ferrag1, Svetlana Mikhaylichenko1, Kagan Kerman1


High swelling hydrogel polymers are three-dimensional networks of cross-linked

polymeric chains. They have the capacity to swell and de-swell extensively due to the

presence of the hydrophilic functional groups attached to their backbone. The chemical

and physical properties of these hydrogels allow them to have various applications in

biotechnology, tissue engineering, biosensors, consumers products such as diapers,

hemostasis bandages and drug delivery systems. The purpose of this study is to

synthesize and characterize a new co-polymer polyvinylpyrrolidone (PVP) cross-linked

with N-methlyenebisacrylamide and also a known co-polymer of acrylamide and N-

methlyenebisacrylamide (PAA). A novel radical polymerization system, which involves

only using a potassium persulfate initiator as well as combining it with a redox system,

was used to synthesize both co-polymers. In this study, we also investigated the swelling

properties of the hydrogels as well as their ability in trapping and releasing molecules in

a controlled manner to provide a method of molecule transport and potentially a drug

delivery system. The drug model used to quantitatively determine the release of a target

molecule from PAA and PVP was curcumin. The release of curcumin was detected and

measured using two types of methods: UV-Vis spectrometry as well as an

electrochemical detection approach, which allowed for a lower detection limit. Both

detection methods successfully showed the release of curcumin from the PAA hydrogels

which can be controlled by varying the concentrations of the cross-linker. Furthermore,

a rheological analysis was done to systematically confirm the gel-like behavior of the

polymers as well as their reusability.

101 - Photoactivation of Inhibitors of Anti-Cancer

Therapy

Reta Bodagh1, Andrew Beharry1


Over-expression of the DNA repair enzyme O6-methylguanine-DNA methyltransferase

(MGMT) diminishes the effects of the anti-cancer alkylating agent, temozolomide (TMZ).

By employing inhibitors of MGMT, such as O6-benzylguanine or PaTrin-2, the

therapeutic effects of TMZ have been shown to substantially increase. However, MGMT

inhibitors are not cancer selective and as a result, MGMT is inhibited in all cells leading

to normal cell toxicity. To this regard, we are modifying MGMT inhibitors with

photoremovable protecting groups such that they are inactive against MGMT in the dark.

By confining light irradiation to cancer cells only, the inhibitors are expected to activate

and inhibit MGMT, thereby increasing the effects of TMZ with reduced toxicity to normal

cells. Using fluorescence-based MGMT activity assays, we have established that caging

these inhibitors diminishes their inhibitory effect on MGMT. The synthesis, purification,

and characterization of these caged inhibitors will be described in this presentation.

102 - Determination of Phosphonium Salt Dissociation

Constants

Rabinththan Ravichandran1, Benjamin Hisey1, Paul J. Ragogna1, James A. Wisner1


Ionic liquids are a class of salts where the salt is observed as a liquid at room

temperature and have melting points lower than that of water. This allows them to be

used in a wide array of applications such as green solvents, as separation agents, and

electrolytes. This project focuses on phosphonium ionic liquids which are a class of

compounds composed of a phosphorus atom at the (V) oxidation state with 4

substituents bound to it as well a counter anion. What has not been determined for these

compounds is the dissociation constant. A dissociation constant describes the

equilibrium of a molecule splitting into its component ions when placed in a solvent.

NMR spectroscopy was used to determine the dissociation constant of different

phosphonium salts that were synthesized for this analysis. The cation that was used was

tributyl-(4-vinylbenzyl)phosphonium and the anions that were used were chloride,

bromide, triflate, tetraphenylborate, bistriflimide, nitrate, and tetrafluoroborate. The

titration was performed by varying the concentration in a window of 0.1 Mm to 0.1M and

then fitting the data into a quadratic equation describing the equilibrium. Origin data

software was used to preform non-linear regression on the data and the dissociation

constants for the chloride, bromide, nitrate, tetraphenylborate and tetrafluoroborate salts

were determined to be 979.7 ± 85.4 M, 57.4 ± 11.1 M, 123.5 ± 33.2 M, 14.7 ± 2.5 M and

46.9 ± 14.9 M respectively.

103 - Synthesis of New Reactive BODIPY Dyes and their

Applications in Solar Cells

Fiona Jeeva1, Svetlana Mikhaylichenko1, Maryam Abdinejad1

1Department of Physical and Environmental Sciences, University of Toronto

Scarborough, 1295 Military Trail, Toronto, M1C 1A4, ON, Canada

Dye-sensitized solar cells (DSSCs) are third generation solar cells gaining in popularity

due to high efficiency relative to their low cost. Traditionally, ruthenium based dyes were

used to as sensitizers; however due to expense and limited resources, research into

organic based dyes have grown substantially in interest. The goal of this project is

synthesis of a novel 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) based

compound conjugated with a triphenylamine derivative for potential use as a dye

sensitizer for DSSCs. The two compounds, 8-phenyl-BODIPY and 4,4’-

dimethoxytriphenylamine (TPA-(OMe)2) were successfully synthesized using a one-pot

reaction with reagents pyrrole and benzaldehyde and an Ullmann type reaction,

respectively. Both products were brominated, with subsequent borylation of the

brominated TPA(OMe)2 in preparation for the Suzuki-Miyaura coupling reaction to obtain

the final product. From UV-Vis analysis, approximately 130 nm bathochromic shift was

observed of the TPA-(OMe)2 when compared to the UV-Vis spectra of triphenylamine

obtained from governmental sources. 15 nm bathochromic shift was shown for the 8-

phenyl-BODIPY with a bromine atom substituted at the b-position. Due to much higher

conjugation and electron donating ability of TPA-(OMe)2, significant bathochromic shift –

indicative of higher DSSC efficiency – is expected of the final product due to the

presence of the additional electron donating groups.

105 - Synthesis of Thermo-responsive and Self-

immolative Polymers from Poly(ethyl glyoxylate)

Kyle Classen1


Stimuli-responsive polymers are interesting materials as they demonstrate different

physical or chemical properties upon exposure to stimuli such as light[1], heat[2], and

acid[3]. Recently, self-immolative polymers (SIPs), a novel class of stimuli-responsive

polymers, have attracted great attention as they undergo depolymerization via an end-

to-end mechanism, initiated by a single bond cleavage at the polymer terminus.[4,5,6] The

Gillies group has developed self-immolative poly(ethyl glyoxlyate)s (PEtGs) that degrade

to potentially non-toxic products, making them of interest for biological applications.[7]

Furthermore, the reactivity of the pendant ester groups of PEtG allows for post-

polymerization modification. It was found by J.F. Lutz that poly[oligo(ethylene glycol)

methacrylates] exhibit thermo-responsive behavior, so by analogy we envisioned that

PEtGs decorated with poly(ethylene glycol) (PEG) side chains would

demonstrate similar thermo-responsive behavior.[8] In this regard, we synthesized

various PEG amines and reacted them with PEtGs under mild conditions to produce

several unprecedented biodegradable SIPs in good yields. These materials were fully

characterized using methods including FT-IR and 1H NMR spectroscopy, gel permeation

chromatography, differential scanning calorimetry, and thermogravimetric analysis. Their

thermo-responsive behavior was studied via cloud point measurements. In this talk, the

synthesis, characterization, and thermo-responsive behavior of these polymers will be

discussed.

106 - The Effect of Oxygen and Nitrite on the Corrosion

of Copper under Nuclear Waste Disposal Conditions

Maryam Mohammad1,2, Joseph Turnbull1,2, David Shoesmith3, Ryan Szukalo3, Mehran

Behazin2, Dmitrij Zagidulin3, Sridhar Ramamurthy9, Clara Wren3

1The University of Western Ontario, 2NWMO, 3The University of Western Ontario, 4NWMO, 5The University of Western Ontario, 6The University of Western Ontario, 7NWMO, 8The University of Western Ontario, 9Surface Science Western, 10The University

of Western Ontario

Nuclear power generation has been a consistent source of energy in Canada for over 40

years, and a permanent method of disposal for used nuclear fuel is being extensively

investigated. Canada's lond-term disposal plan is emplacement of used nuclear fuel

sealed in a copper coated steel container in a deep geological repository (DGR).

Conditions in a DGR following closure are expected to evolve from a hot, aerated humid

environment to a cool, fully anoxic condition. During the aerated humid phase,

HNO3 produced by the radiolysis of the humid air can deliquesce on the copper

container surface. In this project the processes by which HNO3 could corrode the copper

are being investigated using a combination of electrochemical and surface analytical

techniques. The key oxidants under investigation are dissolved O2, HNO3, and nitrous

acid (HNO2), the latter is a product expected to form upon oxidation of Cu by HNO3.

These oxidants appear to react cooperatively on the Cu with the initial production of

Cu+ being important in the overall corrosion process. Cyclic voltammetry technique was

used to investigate the kinetics of reduction of these species and how they interact.

Chloride is one of the anions expected to be dominant in the groundwater composition,

hence series of experiments were designed to explore the effect of chloride. This anion

is known to complex Cu+ as CuClx(1-x)+ and appears to have an influence on the overall

corrosion process.

107 - Synthesis of the KRN 7000 Glycosphingolipid

Acetal Free Analogue

Michael Qaqish1, Michael Reynolds1, John F. Trant1

1University of Windsor, Department of Biochem

Synthesis of the KRN 7000 Glycosphingolipid Acetal Free Analogue: Michael Qaqish,

Michael Reynolds, John F. Trant

Carbohydrates fulfill many roles in biological systems including (but not limited to): acting

as cellular structural supports, mediating cell signaling and acting as an energy supply.

They can also act as “superantigens” for the immune system when part of certain fat

molecules called glycosphingolipids. These molecules are able to activate invariant

Natural Killer T-Cells (iNKT cells); white blood cells that mount a dangerous, non-specific

systemic immune response potentially leading to cell death. However, this same immune

response (if controlled), has promise to act as a last line antiviral and/or a potential

anticancer agent by potentially turning the immune system against a previously ignored

virus, infection or tumour. The identification and synthesis of such immunoactive agents

for clinical and mechanistic applications is of great interest in carbohydrate immunology.

KRN7000 is of particular interest. It was first isolated from a marine sponge and is the

most potent activator of iNKT cells. However, if almost any part of the molecule is

modified, all biological activity is lost. One of the few exceptions is that the

enzymatically-sensitive bond attaching the sugar to the lipid can be replaced with a

stable carbon linkage. However, the synthesis is too long to be commercially useful. We

wish to discuss our approach towards this molecule that attempts to streamline the

approach by very subtly modifying KRN7000 in a new way. The synthesis, and its

implications for biological activity, will be discussed.

109 - Cyclization and Characterization of cis-1-alkenyl β-

aminoalkyl sulfoxides

Scott Sammons1, Adrian Schwan1


ABSTRACT: Stereoselective cyclization of 1-alkenyl β-aminoalkyl sulfoxides and

sulfones holds significance in the synthesis of biochemically active heterocycles.1

Cycloalliin (1) possesses inherent antioxidant and anticancer properties, while 3,5-

disubstituted 1,4-thiazane S-oxide (2) has antibiotic activity.2,3,4 Conversion of 3,5-

disubstituted 1,4-thiazane dioxides to 2,5-disubstituted pyrrolidines (3), known as ant

venom alkaloids, show value in the development of new therapeutic drugs.5 Preceding

endeavors by Söderman and Schwan have led to the thorough characterization of the

stereochemical cyclization of trans-1-alkenyl β-aminoalkyl sulfoxides and sulfones, as

well as the direct conversion of the heterocyclic products to the 2,5-disubstituted

pyrrolidine ant venom alkaloids. Comprehensive characterization of the trans isomer

provides incentive for the determination of the stereochemical cyclization patterns of cis-

1-alkenyl β-aminoalkyl sulfoxides, as the mechanism of cyclization remains currently

unknown. The synthesis of cis-1-alkenyl β-aminoalkyl sulfoxides is to be initiated with L-

phenylalanine starting material, with optimism that the stereochemical patterns will be

determined upon cyclizing the cis isomer. A thiocyanate SN2 attack on the iodinated Boc-

protected β-amino product of the Lange reaction shows promise in accessing the

stereospecific cis isomer desired. An alternate synthetic pathway can be employed,

initiated with a terminal alkyne starting material and utilizing tantalum pentachloride as a

reagent for the reduction of an alkynylsulfide to a cis-alkenylsulfide. The synthesis and

characterization of the cis alkenyl sulfoxide isomer and efforts towards an optimized,

alternative synthetic route will be presented.

110 - Synthesis and characterization of immunologically

active glycolipids isolated from S. pneumoniae

Peter Bahnam1, Greg Yousif2, Emmanuel Igbokwe2, Iraj Sadraei3, John F. Trant4

1Presenter, 2Research Mentors, 3PhD Graduate Student Mentor, 4Research Supervisor

Carbohydrates can act as superantigens for the immune system when they are

conjugated to certain fat molecules as glycolipids. A specific subset of glycolipids can

activate invariant Natural Killer T-cells (iNKT cells) – white blood cells that mediate a

dangerous non-specific systemic immune response that can potentially lead to death.

However, if this same immune response is controlled it has promise to act as a last line

antiviral and/or a potential anticancer agent by potentially turning the immune system

against previously ignored virus-infected or tumour cells. These iNKT cells are found in

all mammals. This is unusual as immune systems normally differ completely between

two individuals, let alone different species. Until recently, the only known activators had

been isolated from sea sponges found off the coast of Japan. However, a few years ago,

two molecules were isolated from dangerous bacteria, Streptococcus pneumoniae, that

can activate this system. The Trant Team is carrying out the first synthesis of these two

compounds; both have biological activity and bypass the non-polar lipid bilayer in the

cells of the tissue they target. The isolated compounds may or may not have been

contaminated, and their structure may be not be correct: we are making these materials

so we can confirm both the actual structure of these materials, and that the observed

biological activity is due to these compounds. Our more efficient synthesis, the

nanoparticle self-assembly behaviour of these materials, and possibly the preliminary

immunological results obtained by our collaborators (Haeryfar group) will be presented.

111 - Domino Palladium–Hydride Insertion/C–H Bond

Activation: Cycloisomerization of 1,6-Diynes

Jose Rodriguez1, Ivan Franzoni2, Katherine Burton3, Amalia Poblador-Bahamonde4,

Mark Lautens5

1University of Toronto, 2University of Toronto, 3University of Toronto, 4University of

Geneva, 5University of Toronto

The use of C-H bond activation has become progressively relevant in the synthesis of

complex organic molecules. This strategy circumvents the need for prefunctionalization

of starting materials, while simultaneously expanding the number of possible synthetic

disconnections. Our work involves application of ammonium halide salts as practical

hydride donors for a novel Pd-catalyzed cycloisomerization of 1,6-diynes. This route

proceeds via a domino reaction, undergoing addition of a Pd-hydride species across a

π-system, followed by intramolecular Mizoroki-Heck reaction, and subsequent C-H bond

functionalization. Experimental data suggests an outer-sphere-type C-H bond activation,

allowing access to formerly unexplored silylated 2-azafluorene derivatives. Several

functional groups were tolerated, and further derivatizations were performed on products

to validate their synthetic utility.

112 - Can Molecular Simulations Help Understand

Alzheimer's Disease?

Xinyu (Linda) Ye1

1Western University

Alzheimer’s disease is one of the leading causes of senile dementia in the elderly; the

formation of extracellular amyloid plaques in neuronal membranes is a hallmark of the

disease. Despite this, the underlying mechanism of toxicity of the amyloid plaques

remain unknown. Previously published work used molecular dynamic (MD) simulations

to observe changes in biological membranes, upon insertion of Ab40 peptides. The

study observed membrane curvature upon Ab40 aggregation, and proposed the Theory

of Frustrated Helices. It stated that the twisted “frustrated” structure of Ab40 favored

curvature of the membrane. This study is a continuation of the previous study, and aims

to use MD simulations to gain insight into the various interactions and perturbations of

Ab40, to understand the mechanism in which the peptides exert its toxicity. The

hydrogen bonding interactions, order parameters, membrane thickness and area per

lipid were investigated in this study.

113 - Optimal Control of Frequency-Swept Pulses for the

Acquisition of Ultra-Wideline Solid-State NMR Spectra

Adam Altenhof1, Austin W. Lindquist1, Lucas D.D. Foster1, Sean T. Holmes1, Robert W.

Schurko1


Solid-state NMR (SSNMR) spectra often feature broad patterns, which range from

hundreds of kHz to several MHz in breadth; those that exceed ca. 250 kHz are

considered ultra-wideline NMR (UWNMR) patterns. Since high-power rectangular pulses

are insufficient for the excitation of UWNMR patterns, special techniques must be used

for their acquisition.[1] Frequency-swept (FS) pulses are utilized for broadband excitation

and refocusing, and are therefore useful in the acquisition of UWNMR spectra.[1] In

particular, Wideband Uniform Rate Smooth Truncation (WURST) pulses have been used

for acquiring UWNMR spectra of both spin-1/2 and quadrupolar nuclides; however,

these pulses have limitations in terms of their excitation bandwidths and ability to

produce distortion-free spectra.[2] We explore two new facets of pulses used in

UWNMR: (i) the use of other FS pulses such as hyperbolic secant (HS) and tanh/tan

(THT) for broadband excitation and refocusing, and (ii) the design of new broadband

pulses via the use of optimal control theory (OCT).[3] In the first case, HS and THT

pulses were tested on spin-1/2 and quadrupolar nuclides, and the results are compared

to those obtained from WURST pulses. In the second case, new OCT Optimized

Broadband Excitation and Refocusing (OCTOBER) pulses, are generated from WURST,

HS, and THT pulses as starting points using OCT.[4]

(1) Schurko, R. W. Acc. Chem. Res. 2013, 46, 1985.

(2) O’Dell, L. et al. Chem. Phys. Lett. 2008, 464, 97.

(3) Garwood, M. et al. J. Magn. Reson. 2001, 155-177.

(4) Tosner, Z. et al. J. Magn. Reson. 2009, 197, 120.

114 - Using Variable Temperature NMR to Examine the

Structure and Stability of Immature Human SOD1

Jeffrey Palumbo1


Amyotrophic lateral sclerosis (ALS) is an adult onset neurodegenerative disease that

can be inherited or arise sporadically, and is associated with protein misfolding. Patients

with hereditary, or familial, ALS commonly develop the disease because of a toxic gain

in function arising from mutations in copper, zinc superoxide dismutase (SOD1). These

mutations generally promote misfolding and aggregation of SOD1 protein, which is

thought to be toxic.

SOD1 undergoes several post-translational modifications during its maturation. These

modifications include the binding of zinc and copper, formation of an intrasubunit

disulphide bond, and dimerization. Generally, immature states are more likely to

aggregate than mature SOD1. In this project, the structural stability of disulphide

reduced, one-zinc bound (E,Zn2SH) dimeric SOD1 has been studied and compared to

disulphide-reduced unmetallated monomeric SOD1 (apo2SH) using variable

temperature NMR experiments. These variable temperature experiments yield amide

proton temperature coefficients, which report on local stability. The stability of the

E,Zn2SH SOD1 is of particular interest for understanding how this little studied

maturation state interacts with the copper chaperone for SOD1, and how its maturation

is impacted by ALS mutations.

The NMR analysis reveals that while there is an overall increase in stability, localized

near the zinc binding site, there is concurrent destabilization of the SOD1 dimer interface

to promote its dissociation and enhance binding to the copper chaperone.

115 - Fluorescent integrated stapled ghrelin(1-20)

analogues for the targeting of GHSR-1a in cancer

Geran B. Tu1, Tyler Lalonde1, Kelvin Tsao2, Jeffrey W. Keillor2, Leonard G. Luyt1,3

1University of Western Ontario, 2University of Ottawa, 3Lawson Health Research Institute

The growth hormone secretagogue receptor type 1a (GHSR-1a) is upregulated in a

variety of cancers which makes it a target of interest for the early detection of

tumors. GHSR-1a can be targeted by modifying the receptor’s endogenous ligand,

ghrelin, to improve binding affinity. Attaching a fluorophore to these ghrelin analogues

allows them to be used as in vitro imaging agents. To reduce the cost of synthesis for

the ghrelin analogues, ghrelin is truncated from 28 amino acids to a shorter

length. However, truncation destabilizes the α-helical secondary structure of ghrelin

which is necessary for binding to GHSR-1a. A fluorescent dye-integrated staple was

reacted with Cys residues on the peptide in the 12th and 16th positions (i, i+4) or the 8th

and 15th positions (i, i+7) with the goal of re-establishing α-helicity and improving binding

affinity to GHSR-1a. The stapled peptides were compared to their unstapled straight-

chain forms, but the cysteine residues were replaced with the bioisostere serine due to

cysteine’s tendency to form disulfide bonds. Circular dichroism (CD) spectroscopy and

fluorimetry were performed on the i, i+7 variant. Based on the CD spectra, serine

versions of both peptides were non-helical and the i, i+7 stapled variant was also non-

helical. The i, i+7 variant had λex=440 nm and λem=485 nm which makes it ideal for use

in fluorescence microscopy. The i, i+4 variant has been synthesized and will be

evaluated in the future. This is the first demonstration of an integrated fluorescent staple

being used to cyclize a ghrelin analogue.

117 - Temporal and Spatial Expression of Giardia

intestinalis Flavohemoglobin

Rubab Fatima1

1Trent University

Giardia intestinalis is a parasitic protist that causes giardiasis, an infection of the small

intestine resulting in diarrhea, nausea, and abdominal cramps. Nitric oxide (NO) is a

toxic free radical generated by the host’s immune system that causes cytotoxicity to

Giardia cells. Giardia encodes several heme proteins, one of which is flavohemoglobin

(gFlHb); flavohemoglobins are nitric oxide dioxygenases used by bacteria to detoxify NO

radicals but are rarely found in eukaryotic organisms. It is likely that Giardia expresses

gFlHb,to counter host-derived nitrosative stress.

In this research, an antibody against gFlHb was used in western blotting and

immunofluoresce microscopy experiments to study the time course of gFlHb expression

in response to nitrosative stress, as well as the spatial localization of gFlHb within the

Giardia trophozoite. Axenic cultures of Giardia trophozoites were exposed to nitrosative

stress using NONOates, a class of compounds that release NO with predictable release

kinetics. Separate time course experiments were run with each of the following

compounds at 0.1 mM concentration: propylamine propylamine NONOate, t1/2 =15

minutes; dipropylenetriamine NONOate, t1/2 =3 hours; diethylenetriamine NONOate,

t1/2 =24 hours. Three time points of treated cells, along with untreated controls, were

then analyzed for each NONOate experiment using westerns blots and

immunofluorescence microscopy to study the temporal and spatial expression of gFlHb,

respectively. Time course experiments showed that the expression of gFlHb is

upregulated in response to nitrosative stress. The localization of gFlHb within Giardia

trophozoites is diffuse throughout the cytoplasm and is not altered with exposure to

nitrosative stress.

118 - Reactivity and Tuning of a Pentanuclear Nickel

Carbide Cluster

Galen Suh1, Manar Shoshani1, Sam Johnson1


The activation and cleavage of strong bonds, such as sp3 C-C bonds and C-H bonds ,is

a challenging, lucrative and important field in chemistry. This is due to the vast

importance of C-C and C-H bond activation across many fields, from pharmaceutical to

petrochemical. Transition metals have seen use in recent years as catalysts for bond

functionalization. This allows reactions involving these difficult functionalizations to be

sustainable and practical. However, what are currently the most efficient choices of late

transition metal catalysts must be improved drastically before they can be used. A

compound discovered in recent years by the Sam Johnson Research Group at the

University of Windsor, a pentanuclear nickel carbide cluster of the form Ni5(iPr3P)5H4C,

shows promising reactivity using an uncommonly studied metal, nickel, which possesses

greatly untapped potential. Thanks to its’ central carbide, the cluster is suspected to

possess greatly increased stability for use in reactions. Using nuclear-magnetic

resonance spectroscopy (NMR), the compound was discovered to perform uniquely

selective reactions with fluorinated aromatics, and through x-ray diffraction

crystallography, two additional modified versions of the cluster were discovered

suggesting its’ potential to be a tunable reagent which can be adapted to specific

reactions. Through further NMR kinetics studies, X-ray diffractometer crystallography

and elemental analysis, the potential for the compound to be a catalyst is to be explored

further in this project.

119 - Progress Toward the Formal Synthesis of

Chanoclavine I

Benjamin Bridge1


Chanoclavine I (4, Scheme 1) is a naturally occurring alkaloid found primarily in

claviceps fungi.1 Many of these alkaloids exhibit biological activity, with effects including

constriction of blood vessels and hallucinations.2 As such, these compounds have

garnered the attention of medicinal and synthetic chemists for their unique scaffolds and

bioactive properties. Here-in we discuss strategies toward a formal synthesis of

chanoclavine I from a novel donor-acceptor (DA) cyclopropane (1). Treatment of the DA

cyclopropane with nucleophilic N-methylhydroxylamine results in the formation of an

intermediate nitrone (2). Upon heating, 2 undergoes a [3+2] nitrone-olefin cycloaddition

to form 3, containing the tricyclic structure of chanoclavine I.

[1] Liu, H.; Jia, Y. Nat. Prod. Rep. 2017, 34, 411-432.

[2] Krska, R.; Crews, C. Food Additives and Contaminants. 2008, 25, 722-731.

121 - Corrective method for density-functional

calculations of hyperfine coupling constants

Jenée Joseph1, Viktor Staroverov1


Density functional theory is extensively used to predict many molecular properties

including the isotropic hyperfine Fermi coupling term. This term is underestimated by the

local density approximation; but generalized gradient approximations (GGAs) perform

better but still produce errors. We investigated the hypothesis that these errors arise in

part as a result of singular nature of GGA exchange-correlation potentials at the nucleus,

where the potential behaves as -c/r, where c is a functional and nucleus-dependent

constant. This affects the spin density at the nucleus and ultimately the Fermi coupling

term. A method to eliminate the singularity is presented by the graphical determination of

the constant. This constant is then added to the nuclear charge of the corresponding

nucleus in order to correct for the singularity. Although the constant could be accurately

determined, there was no significant change in the coupling term. Thus, the singular

behaviour of GGA potentials at atomic nuclei is not a serious defect as far as prediction

of Fermi coupling terms is concerned.

122 - Synthetic Approach to Produce a C-glycoside Tn

Antigen

Advait Desai1, John F. Trant1, Iraj Sadraei1


Many biological processes including bacterial and viral infections (notably HIV and the

flu), immunogenic responses, and cancer pathogenesis/metastasis are mediated by

carbohydrate interactions. An example of such a carbohydrate is the Tn antigen. The Tn

antigen is particularly interesting as it shows up in a large number of different cancer

cells including: gastric, colon, breast, lung, esophageal, prostate, and endometrial

cancer. If the immune system could be trained to target this molecule, then the immune

system could be used to help cure cancer. A key drawback to using this method is the

inherent low in vivo half-lives of carbohydrate containing materials. This Trant Team

project aims to remove the unstable acetal functionality of the Tn antigen by replacing

the exocyclic anomeric oxygen with a methylene (C-glycoside) to make new acetal-free

C-glycoside analogues of the Tn antigen. Removing the labile functionality should result

in greatly enhanced lifetime, and bioavailability relative to the native system with no loss

of activity as the exocyclic oxygen is not involved in the vast majority of molecular

recognition events. This molecule is being made by total synthesis for its incorporation

into new anti-cancer vaccines.

124 - Enzyme Encapsulation and Immobolization of

Deoxyribonuclease 1

Graham Reid1, Steven Rafferty1, Andrew Vreugdenhi1

1Trent University

Abstract:

Enzyme encapsulation is a method of enzyme immobilization that involves

surrounding or enclosing an enzyme in a liposomal vesicle, polymer, sol-gel or other

host material. The purpose of encapsulation is to enhance enzyme stability by

preserving native enzyme structures, activities, and minimizing enzymatic degradation

(1). For this study, encapsulation was paired with another immobilization technique

referred to as cross-linking, which uses a bifunctional reagent to prepare enzyme

aggregates. Formation of these aggregates is beneficial as they lead to areas of highly

concentrated enzyme activity along with high stability and low productions costs (2). In

this work we have used encapsulation and cross-linking in tandem to create a highly

concentrated and protected enzymatic material. We have encapsulated the enzyme

Deoxyribonuclease I, into Santa Barbara Amorphous silica gel (SBA-15). Key

parameters for enzyme encapsulation are maintenance of enzyme activity, enzyme

loading efficiency and reduction of enzyme leaching. The utility of the hosted enzyme

material has been evaluated in terms of its ability to digest double stranded DNA under a

variety of unfavourable conditions.

References:

1)Betancor, L. Luckarift, H.R. 2008. Bioinspired enzyme encapsulation for biocatalysis.

Trends in Biochemistry. Cell Press. 26;10, pp. 566-572

2)Cao,L. van Langen, L. Sheldon, R. 2003. Immobilized enzymes: carrier-bound or

carrier-free?. Current Opinion in Biotechnology. ELSEVIER. 14;4, pp. 387-394

125 - Expanding the Role of CO2 Surrogates in Organic

Synthesis

Timothy Hurst1, Julie Deichert1, Lucas Kapeniak1, Jesse Harris1, Roland Lee2, Philip

Jessop1, Victor Snieckus1

1Queen's University, 2MacEwan University

CO2 is an important building block in organic synthesis and is the basis of the Kolbe-

Schmitt reaction for the commercial production of Aspirin. We will report on the use of

sodium methyl carbonate (SMC) as a surrogate CO2 electrophile in classical

organometallic reactions. Under ambient conditions, SMC is a white solid and can be

used to circumvent the use of excess gaseous or solid CO2. The reactions of SMC with

Grignard and organolithium reagents provide new and general methods for the synthesis

of alkyl, aryl, and alkynyl acids and symmetrical benzophenone derivatives, respectively.

A one-pot procedure for the preparation of unsymmetrical benzo- and aceto-phenones

will be presented as well.

126 - Examining the Effects of Oxidative Damage on

Protein Stability

Drishti Kataria1, Lars Konermann1


Oxidative damage to proteins is closely linked to aging and aging-related diseases.

Oxidation can change the protein structure and net charge, affecting sterics and

electrostatics. In this work we explored the use of electrospray mass spectrometry

techniques to probe oxidation-induced changes in the structure and stability of the model

protein hemoglobin. Specifically, we conducted collision-induced dissociation

experiments. We found that chloramine-T oxidizes methionine residues in the α and β

subunits of hemoglobin. The mass spectra showed that the β subunit is more oxidized

than the α subunit due to its larger number of methionine residues (3 vs. 1). We initially

expected that oxidative damage would have negative effects on protein structural

stability and cause the oxidized hemoglobin to dissociate more readily in the gas phase

compared to the non-oxidized controls. Surprisingly, it was found that oxidized

hemoglobin is less susceptible to dissociation. We tentatively ascribe this behavior to

stabilizing electrostatic effects mediated by newly formed methionine sulfoxide sites.

Further experiments using ion mobility techniques will provide more insights into the

effects of oxidation on the structural stability of hemoglobin.

127 - Naphthalene Dithioimides: Analysis of Steric

Barriers to Thionation

Sarah Mathers1, Paniz Pahlavanlu1, Dwight S. Seferos1


Thionated naphthalene diimides (NDIs) have become an area of active research due

to their potential as n-type organic semiconductor materials. We have previously shown

that the selective dithionation of NDIs can be achieved through the use of sterically bulky

imide substituents and core-flanking groups. We have also noted the decreased

solubility of these compounds upon increased thionation, which has implications not only

for their ability to be studied but also their environmental impact and processing safety.

This project set out to synthesize an NDI with 12-unit polyethylene glycol (PEG) imide

substituents in order to afford increased solubility to the thionated analogues. The need

for core substituents was also investigated using an un-core substituted NDI with 2-

octyldodecyl imide substituents, and it was found that the core substituents were

necessary for microwave thionation. Therefore, we focused on the synthesis of a

bromine core-flanked NDI with mPEG12 imide substituents. From there, we further

investigated the effect of the core and imide substituents in a computational investigation

using steric maps and buried volume calculations to quantify the extent of steric bulk

around thionation sites, in comparison to the size of common thionation reagents. A

variety of different imide substituents and core flanking groups have been analyzed to

determine the minimum steric hindrance necessary to effectively block thionation of a

given carbonyl.

129 - Near-field infrared spectroscopic properties of

boron nitride nanotubes upon polymer binding

Ruben Mirzoyan1, Gilbert Walker1


Boron nitride nanotubes (BNNTs) are inorganic materials with a large bandgap and

interesting optical properties. Under certain frequencies of light in the mid-infrared,

photons couple to the vibrations of the polar lattice to generate surface phonon

polaritons (PhPs), waves that confine energy at the nanotube surface and allow long

distance propagation with low loss. This phenomenon is desirable for sensing and

nanocircuitry applications. Recently, it has been shown that a conducting polymer, poly-

(3-hexylthiophene) (P3HT) interacts strongly with BNNTs and sorts them from reaction

mixtures containing hexagonal boron nitride. The nature of the polymer binding

interaction is not understood, though it is valuable from a practical perspective. Using

scattering-type scanning near-field optical microscopy (s-SNOM), a near-field infrared

spectrum of a single boron nitride nanotube is obtained both with and without the

presence of an interacting polymer. The imaging capabilities enable the discrimination

between the polymer and nanotube, allowing visualization of how the two entities

interact. Furthermore, the possibility of altered PhP propagation due to interaction with

the conducting polymer is considered.

132 - Synthesis of sugar-derived aryl ethers

Jacklyn Liu1, Victoria Dimakos1, Mark S. Taylor1


Aryl ethers are prevalent functional groups in biologically relevant molecules. Transition

metal-mediated processes have greatly enabled the facile synthesis of these types of C-

O bonds. The Chan-Evans-Lam reaction involves a cross coupling of aryl boronic

acids/esters with sp2-hybridized alcohols in the presence of a copper catalyst to form aryl

ethers.1,2,3 Our group has recently reported the regioselective cross coupling of

carbohydrate secondary hydroxyl groups with aryl boronic acids under copper-mediated

conditions to generate novel aryl ethers.4 In this project we investigated the copper-

mediated cross coupling of various substituted aryl boron compounds with sugar-derived

hemiacetals. This method has potential applications in the installation of aryl ether

protecting groups, the construction of complex carbohydrate derivatives, and can

additionally facilitate biological studies.

References

1. Lam, P.Y.S., Clark, C.G., Saubern, S., Adams, J., Winters, M., Chan, D.M.T., Combs,

A. Tetrahedron Lett., 1998, 39, 2941 - 2944.

2. Chan, D.M.T., Monaco, K.L., Wang, R.P., Winteres, M.P. Tetrahedron Lett., 1998, 39,

2933 - 2936.

3. Evans, D.A., Katz, J.L., West, T.R. Tetrahedron Lett., 1998, 39, 2937 - 2940.

4. Dimakos, V., Garrett, G.E., Taylor, M.S. J. Am. Chem. Soc., 2017, 139, 15515 -

15521.

134 - N-Heterocyclic Carbene Ligated t-Butylthiolates of

Ag(I) and Cu(I)

Rachel Pottier1, John Corrigan1


An active area of chemical and materials science research involves the controlled

assembly of metal-chalcogen cluster architectures on the nanoscale (“nanoclusters”). In

particular, the assembly of such monodisperse systems for the Group 11 metal Ag has

yielded a rich structural chemistry.[1] One avenue for their preparation involves the use

of solubilized [Ag-SR]n coordination polymers in conjunction with sulfide sources. In this

work we have developed the preparation of several copper- and silver-thiolate

coordination complexes containing N-heterocyclic carbene (NHC) ligands as precursors

for metal-sulfide cluster complexes. The NHC IPr (IPr=1,3-bis(2,6-

diisopropylphenylimidazolin-2-ylidene) is employed with the copper- or silver-tert-butyl

thiolate to yield either the linear coordination compounds [(IPr)M(SBut)] or IPr containing

metal thiolate clusters depending on the relative amount of NHC used. All complexes

have been characterized through single crystal X-ray diffraction. In further study, these

binary clusters may prove suitable for controlled nanocluster formation.

[1] Y.-P. Xie, J.-L. Jin, G.-X. Duan, X. Lu and T. C. W. Mak, Coord. Chem. Rev., 2017,

331, 54–72.

135 - Photoelectrochemical Reduction of Carbon

Dioxide using Mesoporous Titanium Dioxide Modified

with Copper Nanoparticles.

Molly Labine1, Aicheng Chen1


Conversion of CO2 into alternative fuels has the potential to reduce atmospheric

greenhouse gas emissions produced by fossil fuel combustion while also recycling them

back into valuable chemicals to address our steadily increasing global energy

demand. While copper and titanium dioxide are two well-studied and popular electro-

and photo-catalysts, the practical efficiency of each is limited by large necessary

overpotentials and high recombination rates, respectively. Here, we report on the

photoelectrochemical reduction of CO2 using integrated mesoporous TiO2 and Cu

nanoparticles (TiO2/Cu). Mesoporous TiO2 was created using an electrochemical

anodization process and was further treated electrochemically to improve its

conductivity. Copper nanoparticles approximately 50 nm in diameter were uniformly

deposited onto the mesoporous TiO2 by a photo-assisted method. Scanning electron

microscope (SEM) and X-ray photoelectron spectroscopy (XPS) were employed to

characterize the morphology and composition of the formed TiO2/Cu

nanomaterials. Linear sweep voltammetry and chronoamperometry were used to

assess the electrochemical and photoelectrochemical catalytic activity of the combined

TiO2/Cu nanomaterials toward CO2 reduction, showing a significant synergistic

effect. The facile fabrication and enhanced catalytic activity of the TiO2/Cu

nanomaterials developed in this study make them promising for the efficient

transformation of CO2 into useful products.

137 - Investigating Vibration-Plasmon Coupling in a

Nanoreactor

OCdt. Cresswell1, Dr. Malardier-Jugroot1, Capt. McTaggart1

1Royal Military College of Canada, 2Royal Military College of Canada, 3Royal Military

College of Canada

The existence of vibration-plasmon coupling has been confirmed, however an exact

model for the relationship has not been developed. Through the investigation of the Uv-

Vis spectroscopy of a organic molecules in a nanoreactor in comparison to their

simulated IR spectra, a relationship between the IR and UV bands, and therefore the

vibration and plasmon energies, of simple organic molecules can be examined.

139 - A New Method for the Activation of Donor-Acceptor

Cyclopropanes

Michael Botelho and Michael Kerr

Western University

Regarding the total synthesis of natural products, donor-acceptor cyclopropanes have proven to

be a useful class of organic compounds due to their ability to undergo unique chemical

transformations. These distinctive transformations arise from an electronic “push-pull” effect that

is established by the synergism of the donor and the acceptor group. Herein, a new method

regarding the activation of these polarized donor-acceptor bonds is explored. The method

investigated in this report involves the formation of a phenoxenium ion and its potential ability to

induce interesting nucleophilic additions and/or intramolecular reactions within the substrate.

#SOUSCC2018

Poster Presentation Abstracts

14 - Effect of Substrate Surface Stiffness on Bacterial

Adhesion

Yuelang Chen1, Ruby Sullan1


The initial surface adhesion of Escherichia coli bacteria was studied on polymeric

polydimethylsiloxane (PDMS) of varying stiffness, in order to investigate the effect of

substrate surface rigidity on bacterial adhesion. Different PDMS stiffness was

established by varying the mass ratio between base and crosslinking agent (80:1 for soft

surface and 10:1 for hard surface), where higher degree of crosslinking results in stiffer

surface and vice versa. E. coli bacteria with restored cellulose (cellulose+) and its

knockout mutants, cellulose negative (cellulose-) and curli negative (curli-), were used to

examine how bacterial cell-surface structures influence adhesion on hard and soft

surfaces. After incubation on PDMS substrate at 37oC for 15, 60 and 120 minutes, a

negative correlation was observed, using spinning-disk confocal microscopy, between

percent surface area coverages and PDMS surface stiffness for all three strains. In

addition, bacteria cells tend to form clusters on hard PDMS surface, where Z-stack

imaging showed multiple layers of bacteria in each cluster. On the contrary, on soft

PDMS surface, a uniform monolayer of bacteria was observed for all strains. Our results

suggest that E. coli bacteria preferentially adhere to soft over hard PDMS surface.

16 - Assessing the Structural and Functional

Characteristics of the ADP/ATP Carrier Towards a

Comparative Analysis with Uncoupling Proteins

Michael Fish1, Lillian DeBruin1, Masoud Jelokhani-Niaraki1

1Department of Chemistry and Biochemistry, Wilfrid Laurier University

The ADP/ATP carrier is an inner mitochondrial membrane protein responsible for the

exchange of ATP produced in the mitochondrial matrix for ADP in the cytosol. It is

composed of six, transmembrane alpha helices with three, short, antiparallel helices on

the matrix side. An "alternating access mechanism" has been proposed in which salt

bridges at the matrix and cytosolic faces are disrupted and formed based on the

substrate bound resulting in conformational changes which open the carrier to the

appropriate face. Uncoupling proteins are also found in the inner mitochondrial

membrane, are responsible for proton transport and are thought to have very similar

structure to the ADP/ATP carrier. This research sought to evaluate the structure-function

relationships of the ADP/ATP carrier towards a comparative analysis with uncoupling

proteins using a biophysical approach. The protein was successfully overexpressed in

the bacterial membrane of Escherichia coli using auto-induction and purified using

immobilized metal affinity chromatography (IMAC), confirmed by SDS polyacrylamide

gel electrophoresis (SDS-PAGE) and Western Blot which revealed a monomer and

potential dimer. The far-UV circular dichroism (CD) spectrum revealed minima at 208

and 222 nm, indicating alpha helical structure. Future plans include reconstitution in

proteoliposomes, functional analysis of proton transport and ATP transport using

fluorescence spectroscopy and comparative analysis with uncoupling proteins.

18 - Cln5 plays a role in adhesion, autophagy, cell

differentiation, and phagocytosis in Dictyostelium

discoideum

Sabateeshan Mathavarajah1, Meagan McLaren1, Robert Huber1

1Trent University

Batten disease, clinically known as neuronal ceroid lipofuscinosis (NCL), is a currently

untreatable neurodegenerative disease. There are 13 distinct genes which link to NCL

and encode proteins not completely understood. NCL proteins localize to various

subcellular compartments, and one of these proteins, CLN5, has yet to be fully

characterized in terms of localization and function. Unfortunately, studying CLN5 has

been limited to animal models, since many lower eukaryotic systems lack a homolog of

this gene (e.g., yeast, C. elegans, and D. melanogaster). Our recent work revealed a

CLN5 homolog in the social amoeba Dictyostelium discoideum (gene: cln5, protein:

Cln5), which is recognized as a model organism for biomedical research by the National

Institutes of Health. Specifically, we showed Cln5 secretion and function as a glycoside

hydrolase. Here, we extend this work by using homologous recombination to generate a

cln5 knockout cell line. Similar to mammalian cells, Cln5-deficiency displayed defects in

adhesion and cell differentiation. Additionally, we revealed characteristic NCL

phenotypes such as lipofuscin and trace metal accumulation, and differential activity of

the lysosomal enzymes (alpha-mannosidase and beta-glucosidase). A novel

phenotype we observed was aberrant cell-cell adhesion in cln5- cells. Our data provides

the first evidence that CLN5 function is linked to cell-cell adhesion. Furthermore, we also

show phagocytosis and developmental defects in Dictyostelium. In conclusion, this

research provides new insight into the function of CLN5 in humans that may guide

therapy design, as we have identified two phenotypes that could be used for small-

molecule drug screening (lysosomal enzyme activity).

19 - Develop high efficiency electronic structure

computational method for solid state systems

calculations

Songhao Bao1, Marcel Nooijen1


The general goal of this project is to develop an efficient and accurate, electronic

structure method for the calculation of solid state systems. An important first step is a

Hartree-Fock Self-Consistent Field calculation and the determination of the one-particle

density matrix. We developed a scheme to calculate the density matrix using a similarity

transformation analogous to the Coupled Cluster method, but applied to a periodic one-

body hamiltonian. A general python program was written to calculation density matrix

from model block Huckel 1d periodic system. Both a conventional k point scheme and

the coupled cluster based similarity transformation scheme was applied. A few test

cases were examined and the result of calculations with both methods and were

compared to test the efficiency and accuracy of the latter scheme. The new CC scheme

proved accessible, and the translational symmetry and real space sparsity was

evaluated. In the future, this similarity transformation algorithm can be implemented for

the Hartree-Fock calculation using realistic atomic orbital integrals. More importantly a

similar idea is applicable for the full Coupled-Cluster calculation with correlated wave

functions for periodic systems by introducing periodic localized orbitals (PLOs), which

would enhance the efficiency and accuracy of current computational method for solid

state systems.

42 - A novel enzyme based platform coupled to mass

spectrometry for the identification and screening of

toxic reactive metabolites from anti-thyroid drugs

Felicia Leung1, George Luka1,2, Shadi Dalili1, Heinz-Bernhard Kraatz1,2

1University of Toronto Scarborough, 2University of Toronto

Metabolic activation of sulfur based anti-thyroid drugs results in the formation of toxic

reactive metabolites. These metabolites covalently modify proteins, during the first step

in drug-induced toxicity. Methimazole is a commonly used sulfur based anti-thyroid drug

associated with idiosyncratic toxicity. Bioactivation of Methimazole results in the

formation of reactive metabolites that are mainly responsible for this adverse drug

reaction. Current drug metabolism and development are based on using microsomal

assays to generate reactive metabolites. The generated metabolites are then trapped,

collected and tested. Methimazole, however, deactivates enzymes involved in its

oxidation. Furthermore, due to the complexity of the matrices and the low concentration

of toxic reactive metabolites, these techniques exhibit low sensitivity and selectivity. This

makes it not suitable for studying reactive metabolites resulting from the bioactivation of

anti-thyroid drugs, a necessary step in the anti-thyroid drug development process.

In this research, an enzyme based screening platform was developed to generate

reactive metabolites from anti-thyroid drugs. The screening platform involved the use of

a genetically modified oxidoreductase enzyme. This enzyme is capable of selectively

oxidizing anti-thyroid drugs and generating its reactive metabolites. The activity of the

engineered oxidoreductase was tested against Methimazole using ultraviolet-visible

spectrophotometry. Next steps include coupling this developed platform with mass

spectrometry to detect and characterize the reactive metabolites. The metabolites

generated by the developed platform will be compared to those generated using

biological microsomes and other chemical oxidants. Next steps include the synthesis of

a selenium analogue of Methimazole for testing with the developed screening platform.

45 - Measurements of Atmospheric HCl in Toronto To

Understand Reactive Chlorine Chemistry

Andrea Angelucci1, Teles Furlani1, Cora Young1, Trevor VandenBoer1

1York University

Production of ozone in the atmosphere is typically initiated by hydroxide radicals. It has

also been shown that tropospheric ozone can lead to various adverse health

effects2. Chlorine radicals have been found to produce more ozone per mole than

hydroxide radicals can1. One major reservoir for chlorine in the troposphere is the

formation of HCl, which occurs via proton abstraction from organic compounds. In this

study, HCl was measured using a Picarro Cavity Ring-Down Spectrometer (CRDS) in

ambient outdoor air (≈220m above sea level). Complimentary NOx, O3, and solar

irradiance measurements were also made using an EcoTechEC9841 (LDL<0.4ppb), an

EcoTech Serinius 10 (LDL < 0.5 ppb), and a solar radiation smart sensor (paired with a

HOBO MicroStation data logger), respectively. Measurements were done at York

University in Toronto, Ontario (43.77N, 79.51W) between late February and early March

2018. We used this data to further validate the HCl measurement technique and better

understand the chemistry of atmospheric reactive chlorine.

1. Young, C. J., Washenfelder, R. A., Edwards, P. M., Parrish, D. D., Gilman, J. B.,

Kuster, W. C., … Brown, S. S. (2014). Chlorine as a primary radical: Evaluation of

methods to understand its role in initiation of oxidative cycles. Atmospheric Chemistry

and Physics, 14(7), 3427–3440.

2. Lippmann M. Health effects of tropospheric ozone: review of recent research

findings and their implications to ambient air quality standards. J Expo Anal Environ

Epidemiol. 1993 Jan-Mar;3(1) 103-129. PMID: 8518544.

49 - The Synthesis and Characterization of Alkynyl

Substituted Dibenzanthracenes

Cassandra Neter1, Kenneth E. Maly1


Liquid crystals are materials that exhibit properties intermediate between a crystalline

solid and an isotropic liquid. This unique phase is commonly referred to as the

mesophase and therefore, liquid crystals are identified as mesogens. This research

focuses on discotic mesogens which are flat disc-like molecules possessing a polycyclic

aromatic core and flexible peripheral side chains. In the liquid crystalline phase, it is

hypothesized that these molecules rearrange into hexagonal columnar mesophases due

to π-π interactions, allowing charge transport to occur along the columnar axis. Since

they are capable of promoting charge transport, discotic liquid crystals are of interest

for potential applications such as organic semiconductors and photovoltaics. Previous

research in the lab has explored various derivatives of dibenz[a,c]anthracene, and

through various techniques, it was determined that electron withdrawing groups attached

to the aromatic core caused the compound to display a mesomorphic phase. The

objective of this research is to prepare an alkyne-substituted dibenz[a,c]anthracene

derivative and, once synthesized, characterize its properties through POM (polarized

optical microscopy) and DSC (differential scanning calorimetry). Our progress towards

the synthesis of the target compound will be reported. Through this research, it

is possible to determine the effects of alkynyl substituents at the 10 and 13 positios on

the mesomorphic properties of dibenzanthracenes.

Figure 1. Target compound.

52 - Stimuli Responsive Hydrogels and their Self-

Shaping Applications

Darius Hung1, Yun Feng Li1, Dr. Eugenia Kumacheva1


Soft materials that can undergo shape transformations in response to changes in

ambient environment have promising applications in tissue engineering, robotics and

biosensing. Generally, stimulus-responsive materials attain two stable shapes,

corresponding to the “on” and “off” states of the external trigger. Primary and binary

hydrogels incorporating NIPAM, AMPS and 1’-3’-3’-Trimethyl-6-hydroxyspiro(2H-1-

benzopyran-2-2’-indoline) were synthesized. The composite gel sheet was patterned to

introduce small-scale multiple polymer components with distinct compositions. In

response to different stimuli, the non-Euclidean sheets undergo differential swelling or

shrinkage, which creates internal stresses within the gel sheet. Through minimization of

elastic energy, the hydrogels transform into specific and controlled three-dimensional

morphologies. By additionally exploiting stimuli-induced ring opening and closing of the

spirobenzopyran moiety, careful manipulation of external stimuli allowed an in-depth

study on the degree of size and shape transformations possible for our system. The

obtained insight into the relationships between stimulus and hydrogel morphology will

allow for future development of self-learning cognitive gels, that will have particular

importance and relevance in the field of soft matter.

60 - Towards the synthesis of fluoro-substituted

dibenz[a,c]anthracenes using the Wittig reaction

Kegan Moran1, Kenneth E. Maly1


Liquid crystals have recently become an area of great interest in synthetic organic

chemistry for their potential use as organic semiconductors. Dibenz[a,c]anthracenes are

commonly used in our group as a core for discotic liquid crystals. Alkoxy-substituted

dibenz[a,c]anthracenes have been previously shown to display columnar liquid crystal

phases. Their liquid crystalline temperature range broadens when substituted with

electron withdrawing groups that promote pi-pi interactions. The objective of this

research is to prepare a fluorinated alkoxy-substituted dibenz[a,c]anthracene to

investigate its liquid crystalline properties. It is expected that using fluoro substituents will

greatly increase pi-pi interactions via arene-perfluoroarene interactions, resulting in a

broader liquid crystalline temperature range compared to its non-fluorinated equivalents.

Presented will be an overview of discotic liquid crystals and arene-perfluoroarene

interactions as well as the work towards the synthesis of the target molecule. Access to

this molecule has been attempted using an approach that employs the Wittig reaction

between a fluoro-substituted phosphonium salt and an alkoxy-substituted phenanthrene

quinone.

61 - The Use of Microfluidic Chemostats for the

Observation of Conjugation between Escherichia coli

S17-1 and BL21(DE3) pLysS Strains

Sumaiya Baig1, Reta Bodagh1, Gurjit Mander1, Yanming Qi1, Steven Chatfield2, Paul

Piunno1, Joshua N. Milstein1

1University of Toronto Mississauga, Department of Chemical and Physical Sciences, 2University of Toronto Mississauga, Department of Biology

A microfluidic chemostat has been developed for investigations of bacterial conjugation

dynamics. The chemostat is a polydimethylsiloxane (PDMS) on glass microfluidic device

made by inexpensive and easily accessed soft-lithography techniques based on the use

of toner-on-thermoplastic molds. The device has been designed to permit for controlled

growth and observation of cells within a small chamber (~ 2 μL volume) all the while

permitting for accurate control of environmental conditions, including temperature,

nutrient concentrations and total cell concentrations. The utility of the chemostat will be

assessed via studies of the dynamics of plasmid conjugation between two Escherichia

coli strains, namely S17-1 and BL21(DE3) pLysS. These investigations may serve as a

model for future investigations of the spread of antibiotic resistance genes in bacteria, a

rising global health concern. The design, fabrication, and evaluation of the microfluidic

chemostat will be discussed, along with preliminary results of comparative

investigations, in which the results obtained using the chemostat will be compared to

those obtained from the use of traditional culturing techniques.

62 - Optimizing a Decay Vessel for Continuously

Monitoring the Progression of Soft Tissue Decay in the

Laboratory

Maliha Asif1, Jonathan Abraham1, Paul Piunno1, Ulrich J. Krull1, Marc Laflamme1

1University of Toronto Mississauga, Department of Chemical and Physical Sciences

Preservation of soft tissue, such as muscles, nerves and blood vessels, occurs only

under very specific environmental and geochemical conditions; however, the processes

associated with soft tissue preservation are not clearly understood. Current research in

taphonomy aims to characterize the geochemical environment which forms in proximity

to decaying tissue. Differences in sediment permeability and oxygen availability have

been demonstrated to be instrumental in the processes of decay and preservation,

which lead to the formation of a decay microenvironment. A vessel was constructed to

allow for the monitoring of a decay microenvironment and designed to accommodate the

attachment of pH electrodes, CO2 gas sensors, and dissolved oxygen probes. An

Arduino microcontroller based data acquisition system was created to log data from

multiple chemical sensors in the sediment and in the surrounding aqueous environment.

The design, calibration and results from preliminary investigations using this vessel will

be discussed. Future taphonomical experiments can utilize this decay monitoring system

for the observation and replication of biogeochemical processes influencing the

preservation and decay of soft tissue in a laboratory setting. Understanding the

preservation of exceptional soft tissue fossils, such as those found in the Burgess Shale

of British Columbia, can allow for improved interpretation of the fossil record and

improved linkages to be assembled between life forms from the Cambrian era with

extant organisms, thereby providing improved phylogenetic and morphological

information about preserved communities.

64 - Borinic Acid Catalyzed Ring-Opening of an Acyclic

3,4-Epoxy Alcohol using Substituted Aniline

Nucleophiles

Liwah Keller1, Grace Wang1, Mark Taylor1

1University of Toronto,

Epoxy alcohols are a useful intermediate in synthesizing numerous multi-functionalized

molecules such as polyols, monosaccharides1, and other substituted heterocycles2 and

carbocycles3. Often, the epoxide ring is opened through an acid- or base- catalyzed

attack by a heteroatom nucleophile, to produce a beta-hydroxy compound. Although

there have been numerous catalysts made for the selective nucleophilic ring-opening of

2,3-epoxy alcohols, there are few that are effective in catalyzing these reactions regio-

selectively for 3,4-epoxy alcohols. The few catalysts that have been designed are metal-

based4,5,6,7. In this project, a different approach is used— a diaryl borinic acid catalyzes

ring-opening reactions of an acyclic 3,4-epoxy alcohol, with various substituted aniline

nucleophiles. The 3,4-epoxy alcohol substrate was synthesized in a three step-process.

The products were characterized by NMR analyses.

References

1. Otzen, D.; Voss, J.; Adiwidjaja, G. Phosphorus, Sulfur Silicon Relat. Elem. 2006,

181(6), 1249–1270.

2. Kondapi, V. P. K.; Soueidan, O.-M.; Hosseini, S. N.; Jabari, N.; West, F. G. Eur. J.

Org. Chem. 2016, 2016(7), 1367–1379.

3. Guan, Y.; Bissantz, C.; Bergstrom, D. E.; Link, A. Arch. Pharm. 2012, 345(9), 677–

686.

4. Uesugi, S. I.; Watanabe, T.; Imaizumi, T.; Shibuya, M.; Kanoh, N.; Iwabuchi, Y. Org.

Lett. 2014, 16(17), 4408–4411.

5. Wang, C.; Yamamoto, H. J. Am. Chem. Soc 2015, 137(13), 4308–4311.

6. Kim, Y. H.; Kwon, D. W.; Cho, M. S. Synlett 2003, No. 7, 0959–0962.

7. Alvarez, E.; Nunez, M. T.; Martin, V. S. J. Org. Chem.1990, 55(11), 3429–3431.

66 - Urea-linked Polymerization of Primary Amino

Porphyrin Complexes in Mild Conditions with CO2

Caitlin Dao1, Billy Deng1, Maryam Abdinejad1, Bernie Kraatz1, Xiao-an Zhang1


The N-C bonds that can be formed from capturing carbon dioxide (CO2) with amine

solutions lead to the production of urea derived intermediates, compounds, and

polymers for potential applications in various industries such as electropolymerized films,

photonic materials, and chemical sensors. Using amino porphyrins, we demonstrated

selective synthesis of urea-derivative polymers from respective mono- and cis- amino

porphyrin complexes, wherein product yields were selectively generated by altering gas

flow and reaction times at room temperature.

Compared to traditional syntheses of polyureas involving the toxic chemical phosgene,

we present a catalyst-free and relatively rapid synthesis as a low-cost and

environmentally-conscious alternative that can be performed under mild conditions.

69 - Investigation of Protein Folding, Aggregation and

Substrate Binding Sites Using High Resolution Mass

Spectrometry

Jeremy Wong1, Rebecca Jockusch1


Misfolded proteins can cause protein aggregation and cluster formation, which ultimately

may lead to amyloid fibrils as an end product. Amyloid fibrils and protein cluster (plaque)

formation are associated with several neurodegenerative diseases including

Parkinson’s, Alzheimer’s and Huntington’s diseases. Over the past 150 years, extensive

research efforts have been poured into studying the mechanisms of amyloid fibril and

plaque formation. Some recent studies suggest that, at least for Alzheimer’s disease, the

toxic species is not the insoluble end products, but smaller soluble oligomers composed

of a number Ab monomers. It would be useful to develop methods to study the early

stages of protein aggregation and, in particular, how putative drugs affect early stages of

the aggregation process. Here, protein aggregation is studied using Mass Spectrometry

(MS). With the development of soft ionization techniques such as electrospray ionization

(ESI), it is possible to bring big biological molecules such as proteins and their

complexes into the gas intact. Compared to other conventional methods of studying

protein aggregation, MS is advantageous due to the minimal sample prep required,

small amount of sample required, and the ability to distinguish different oligomeric

species based on mass.

71 - Poly(norbornene) Dopamine Polymer Electrode for

Lithium Storage

Luke Kyne1, Bryony McAllister1, Tyler Schon1, Dwight Seferos1


Organic polymers are environmentally-sustainable and inexpensive alternatives to

metal-based electrodes used in modern energy storage devices. Among these, catechol-

dervied pendant polymers have been synthesized as precursors to polymeric ortho-

quinones, which have high charge-storing capabilities. In this work, a poly(norbornene)

backbone with dopamine pendant groups was synthesized for use as a cathode material

in lithium-ion batteries. This two-step, semi-synthetic methodology was effective in

minimizing reaction complexity while maximizing yield. The polymer is observed to have

high operating voltage and capacity in a lithium-ion battery system, making the electrode

material favorable for use in industrial applications. Electronic properties were optimized

when combined with Super P carbon black and polyvinylidene difluoride, before

being deposited on aluminum foil and thoroughly characterized via electron

microscopy. This new material represents an important contribution to the current array

of organic polymer electrodes, and further advances the field of renewable, high-

performance energy storage technology.

73 - Application of Reductive Transposition in the

Synthesis of Pancratistatin

Nolan Nardangeli1, Ringaile Lapinskaite1, Tomas Hudlicky1

1Brock University

The synthetic approach towards pancratistatin, an anticancer compound from the

Amaryllidaceae family of plants, will be presented. The chemoenzymatic process from

m-dibromobenzene will be described, along with the route from natural narciclasine,

producing compound 4. The proposed common intermediate, 2-epi-7-

methoxynarciclasine 4, is envisioned as the key intermediate for the application of a

reductive transposition strategy to the synthesis of pancratistatin.

74 - Mild Metal Mediated Cyclization of a Thiourea to a

Substituted 2-Aminobenzothiazole

Zachary Schroeder1, Lana Hiscock1, Louise N. Dawe1


Benzothiazoles are a highly sought and privileged scaffold for their frequent

bioactivity.1,2,3 The use of expensive metals, such as palladium and ruthenium coupled

with the disposal of halogenated materials resulting from the use of halide leaving

groups, present drawbacks to previous reported syntheses.4,5 Herein, the use of

stoichiometric copper(II) or gold (III) to induce the cyclization of substituted thiourea in an

aryl C-H bond breaking reaction will be presented.6 Benzothiazoles were confirmed

through NMR, IR and X-ray crystallography. Extension of this work to achieve the same

transformation, using Fe(III) salts, could provide access to benzothiazole products in a

green and highly tunable way, with promising versitility.7

(1) Ali, R. et al. J. Chem. 2013, 2013, 1–12.

(2) Seth, S. Antiinflamm. Antiallergy. Agents Med. Chem. 2015, 14 (2), 98–112.

(3) Sharma, P. C. et al. J. Enzyme Inhib. Med. Chem. 2013, 28 (2), 240–266.

(4) Sharma, S. et al. Org. Lett. 2016, 18 (3), 356–359.

(5) Joyce, L. L. et al. Org. Lett. 2009, 11 (13), 2792–2795.

(6) Schroeder, Z. W. et al. Acta Crystallogr. Sect. C Struct. Chem. 2017, 73 (11), 905–

910.

(7) Shang, R. et al. Chem. Rev. 2017, 117 (13), 9086–9139.

75 - Total Synthesis of (-)-Oxycodone

Jared Thomson1, Tyler Bissett1, Prof. Tomas Hudlicky1

1Brock University

An approach towards the total synthesis of (-)-oxycodone will be presented. Key steps

include a Suzuki cross coupling of A- and C-ring fragments, an Arndt-Eistert

homologation, an intramolecular Friedel-Crafts cyclization and a proposed stereospecific

oxidative dearomatization step, inspired by a previous synthesis1, to install the key C-14

hydroxyl group. The aim of the project is to provide a shorter, more efficient synthetic

pathway towards (-)-oxycodone.

(1) Kimishima, A.; Umihara, H.; Mizoguchi, A.; Yokoshima, S.; Fukuyama, T. Org. Lett.,

2014, 16, 6244-6247.

77 - Nickel-Catalysed Aminations of Diaryl Ethers

Alethea Lee1, Chad Orsini1, Sophie Rousseaux1

1Department of Chemistry, University of Toronto

Aryl-amines and N-aryl heterocycles are widely employed as building blocks in synthetic

molecules and pharmaceutical agents.1 Over the past decade, various metal-catalyzed

cross-coupling reactions have been developed as valuable tools for the construction of

C(sp2)-N bonds.2,3,4 Nickel represents an economical and sustainable cross-coupling

approach as a more earth-abundant transitional metal. 5,6 We have developed a Ni-

catalyzed coupling of a naturally derived aryl ether from the plant source – lignin, with

various aniline derivatives in good yields. As the second most abundant biopolymer on

earth, lignin, along with its high content of aromatic groups, serves as an ideal candidate

for a renewable feedstock in the synthesis of aromatic compounds.7 This presentation

will focus on the amine substrate scope of the reaction as well as approaches on the

functionalization of by-products in such reaction.

(1) Cho, S. H.; Kim, J. Y.; Kwak, J.; Chang., S. Chem. Soc. Rev. 2011, 40, 5068.

(2) Hartwig, J. F. Acc. Chem. Res. 2008, 41, 1534.

(3) Surry, D. S.; Buchwald, S. L. Angew. Chem. Int. Ed. 2008, 47, 6338.

(4) Evano, G.; Blanchard, N.; Toumi, M. Chem. Rev. 2008, 108, 3054.

(5) Chirik, R.; Morris, R. Acc. Chem. Res. 2015, 48, 2495.

(6) Dunetz, J. R.; Fandrick, D.; Federsel, J. Org. Process Res. Dev. 2015, 19, 1325.

(7) Kärkäs, M. D.; Matsuura, B. S.; Monos, T. M.; Magallanes, G.; Stephenson, C. J.

Org. Biomol. Chem. 2016, 14, 1853.

89 - Optical biosensing of oligonucleotide modified gold

nanoparticles by induced DNA disassembly

Nicholas Colombo1, Gurbrinder Ghotra1, Jennifer Chen1

1York University

Gold (Au) nanoparticles (NPs) participate in a broad range of applications from

bioimaging, clinical diagnosis to therapy, due to their water-solubility, drug-loading

capacity, and capability of surface-modification, however they can easily aggregate in

solution and have potential biotoxicity, which can limit their applications.1 In this work, Au

NPs are used as probes for colorimetric optical biosensing of nucleic acids to increase

signal intensity, sensitivity, and specificity. Au NPs were functionalized with sequence 1

and sequence 2 with varying density using a diluent DNA. Target DNA-210 is an analog

of miRNA-210, which is a micro RNA biomarker that is overexpressed in cells affected

by cardiac disease or cancer. Kinetics of self-assembly and disassembly

of oligonucleotide modified Au NPs were monitored using UV-visible spectrophotometry.

The absorbance ratio at 526nm versus 650nm was monitored over time during the

disassembly induced by target DNA-210, and then monitored during the temperature

induced denaturation disassembly. The effect of surface density of the oligonucleotides

on the assembly and disassembly process was examined to compare efficiency

of assembly and disassembly. Lastly, urea-page electrophoresis was used to quantitate

the density of the linker and diluent sequences on the nanoparticles.

94 - Exploring and optimizing sulfenate alkylation

reactions for applications in natural product synthesis

Adam Riddell1, Adrian Schwan1


One of the compounds responsible for the aroma of a crushed or heated shiitake

mushroom is a sulfur-containing 7 membered ring known as lenthionine. Lenthionine is

made by an enzymatic process that occurs when the mushroom is crushed causing

lentinic acid to be converted to lenthionine.1 Synthesizing lentinic acid would be

advantageous for artificially creating the scent or flavour of a shiitake mushroom.

Utilizing a sulfenate approach to synthesize lentinic acid would provide a highly versatile

method which requires no subsequent oxidation of the sulfurs. Sulfenate anions

(RSO⁻ M+) are the conjugate base of sulfenic acids and have value in the synthesis of

desired sulfoxides due to the prochirality of sulfur and their potential in stereoselective

reactions. The Perrio and Schwan groups have developed methods for generating these

highly reactive sulfenate anions in situ which can then be reacted with a variety of

electrophiles such as alkyl halides.2,3 The primary investigation of this work will involve a

building block analysis of how best to synthesize the sulfur-carbon backbone of lentinic

acid using various sulfenate anions and electrophiles. Subsequent work will focus on

increasing the rate at which these investigated reactions take place.

1 Yasumoto, K.; Iwami, K.; Mitsuda H. Agric. Biol. Chem. 1971, 35, 2070-2080.

2 Caupène, C.; Boudou, C.; Perrio S.; Metzner P. J. Org. Chem. 2005, 70, 2812-

2815. 3 Singh S. P.; O’Donnell J. S.; Schwan A. L. Org. Biomol. Chem. 2010, 8, 1712-

1717.

95 - Preparation of Various β‑ Amino Iodides and

Bromides for Alternative Synthetic Approaches to

Sulfenate Substitution

Nolan Frame1


N-Protected-Β-amino sulfoxides have found plentiful use as organocatalysts, chiral

ligands, and precursors in biologically active compounds. 1 The current synthetic

approach to Β-amino sulfoxides involves the reaction of sulfenates with amino iodides or

bromides and the use of tert-butyloxycarbonyl (BOC) as the primary protecting group.

Previous investigations by Söderman and Schwan utilizing N-BOC protected Β-amino

iodides and arenesulfenates provided yields of 71-92% with diastereomer ratios

averaging 9:1. 2 This research explores and extends the variety of N-protected Β-amino

iodides and bromides to react with sulfenates. Primary investigations will involve large,

polar protecting groups to maintain specific chirality in the α-carbon to the amine group

in addition to inducing sulfur stereogenicity through steric hindrance and charge

stabilization of the sulfenate counterion.

1. Otocka, S.; Kwiatkowska, M.; Madalińska, L.; Kiełbasiński, P. Chemical Reviews

2017, 117 (5), 4147–4181.

2. J. Org. Chem. 2013, 78, 1638−1649

104 - Synthesis of Cyano-substituted carbene-stabilized

phosphorus(I) cations

Erica Dionisi1, Justin F. Binder1, Tricia Breen Carmichael1, Charles L.B.Macdonald1


There are an increasing number of phosphorus(I) compounds appearing in literature due

to interest in their fundamental properties and potential applications.1,2 Macdonald’s

group has developed a versatile synthetic approach for the generation of carbene-

stabilized PI compounds using an easily prepared phosphorus(I) transfer agent.3,4 Little

attention, however, has been paid to the effect of incorporating electron withdrawing

groups on these cations. We report a streamlined method for the synthesis of cyano-

substituted NHC-stabilized P(I) salts from triphosphenium triflate and in situ generated

carbenes. Structures created in the synthetic pathway were isolated and characterized

by IR, NMR and XRD techniques. There is potential for future work using these

molecules for studies of self-assembled monolayers, with the possibility of using the

cyano-substituents as a handle for characterization or post modification with interesting

functional groups.

1. B. D. Ellis and C. L. B. Macdonald, Coordination Chemistry Reviews., 2007, 7, 936-

973

2. J. F. Binder, S. C. Kosnik and C. L. B. Macdonald, Chem. Eur. J., 2018, 24, 3556-

3565

3. B. D. Ellis and C. L. B. Macdonald, Inorg. Chem., 2006, 45, 6864–74

4. E. L. Norton, K. L. S. Szekely, J. W. Dube, P. G. Bomben and C. L.

B. Macdonald, Inorg. Chem., 2008, 47, 1196–203

108 - Development of a Next Generation Covalent MRI

Tag Based on Manganese Porphyrin

Keith Tang1, Edmond Wong1, Xiao-an Zhang1


Magnetic resonance imaging (MRI) is a non-invasive technique that provides detailed

morphological, physiological, and functional information. However, this technique is often

limited by low sensitivity, thus contrast agents (CAs) are applied to enhance tissue

contrast and improve sensitivity (characterized by longitudinal relaxivity - r1). While

conventional CAs lack molecular specificity, development of a molecular MRI tag for

conjugation with diseases-targeted ligand, i.e. antibody, have the potential to improve

specificity. Clinically approved gadolinium (Gd) based CAs have several drawbacks

which include Gd-toxicity, low stability, and suboptimal sensitivity. However, new

manganese(III) porphyrin (MnP) CAs developed by us have shown high relaxivity at

clinical magnetic fields, high stability, and lower toxicity of Mn than Gd. The design of our

porphyrins were developed in-part based on the Solomon-Bloembergen-Morgan model

by optimizing molecular tumbling rate to increase r1. Earlier MnPs containing sulfonate

groups developed in our group have high r1 at clinically relevant fields, however suffer

from large bulky phenyl groups inducing unwanted hydrophobic interactions lowering

target specificity and solubility. Herein we report the development of a novel MnP,

MnTriCP-PhNH2 containing small polar carboxylate groups and its conjugation to a

polymer backbone for use as a covalent MRI tag.

MnTriCP-PhNH2 was successfully synthesized, using a step-wise di-pyrrolemethane

strategy. The structure is fully characterized by NMR, UV-vis, ESI-MS, HPLC, and Mn-

atomic absorption spectra. The preliminary results on protein conjugation will be

discussed. Next steps are to quantitatively measure the r1 relaxivity at low and high

magnetic field strengths and to identify the in vivo imaging potential.

116 - The secondary structure and membrane

association of the M2- subdomain of TOC159, a protein

of the chloroplast outer membrane

Neil Jurkiewicz1, Dr. Matthew Smith1


On the Chloroplast outer envelope lies the Translocon at the outer envelope membrane

of the chloroplast (TOC complex) which translocates pre-proteins into the chloroplast.

The core of the TOC complex is formed by two GTPase receptors, Toc159 and Toc-34,

and a β-barrel channel protein Toc-75. Toc159 contains 3 domains one of which is the

M-domain which associates with the membrane; however the nature of the association

with the membrane is unknown. Secondary structure prediction analysis of the M-

domain revealed a sub-domain (called M2) that is rich in β-strands, that also aligns with

a known β-helix protein. This led to the hypothesis that the M2 sub domain forms a β-

helix which is involved in membrane association. Our research is aimed at identifying the

secondary structure of the M2 sub-domain of Toc159 (Toc159Mβ) using circular

dichroism (CD) by first purifying the recombinant his-tagged Toc159Mβ using affinity

chromatography. The purified Toc159Mβ will be analyzed with CD to measure its

secondary structure content. Surface plasmon resonance (SPR) will be used to test the

ability of Toc159Mβ to associate with membranes. Determining the secondary structure

and testing the membrane association of Toc159Mβ will advance our understanding of

intracellular trafficking to organelles and also gain a better understanding of atypical

membrane-protein association.

120 - Synthesis of Supramolecular Vanadate Receptors

– Structural Mimics of Vanadium Haloperoxidase

Kit Adriano1, Lana Mikhaylichenko1, Xiao-An Zhang1


Vanadium haloperoxidases are natural enzymes which can catalyze halogenation of

organic substrates. These enzymes utilize vanadium in the form of vanadate as a

cofactor along with hydrogen peroxide to perform the reaction. This on-going study

extends upon the results of a previous work (Zhang and Woggon, 2005) where a

structural mimic of vanadium haloperoxidase was successfully synthesized. The

supramolecular compound showed binding preference for pyrovanadate (V2O74-) and

compound-vanadate complex was found to catalyze bromination of activated C-H bonds.

This work aims to synthesize another structural mimic of the enzyme albeit with binding

preference to monovanadate (HVO42-) instead of pyrovanadate to mirror the natural

enzyme. Extending the previous work, four novel basket-shaped guanidinium receptors

were attempted to be synthesized containing the tripodal ligand tris(2-aminoethyl)amine.

Four different moieties where introduced at each N-terminal of the tripodal ligand:

benzene, propane, pentane and dodecane. Thiourea derivatives for the four moieties

were successfully synthesized while only the dodecyl moiety has been successfully

transformed into its guanidinium derivative, as confirmed by ESI-MS and NMR

spectroscopy. Analyses employed in the previous work (Zhang and Woggon, 2005) such

as 51V-NMR and 1H-NMR are currently being used to characterize the binding between

guanidinium receptor and the vanadate in aqueous and organic solutions.

123 - Remarkably High Stabilities of MnTCP: A Non-Gd

Extracellular MRI Contrast Agent

Naixin Zhao1, Henry Tieu2, Xiao-an Zhang3

1Department of Chemistry, 2Department of Physical and Environmental Science,

Department of Chemistry, 3Department of Physical and Environmental Science,

Department of Chemistry and Department of Biological Sciences, University of Toronto

Scarborough, Toronto, Ontario, Canada

Magnetic resonance imaging (MRI) is a high resolution, noninvasive imaging technique

widely applied in clinical diagnoses. By administering paramagnetic contrast agents, the

sensitivity and image contrast can be significantly improved. Gadolinium-based contrast

agents (GBCAs) are most popular for current clinical MRI scans. However, reports had

been pointed out the release and accumulation of toxic GdIII ions could occur from these

GBCAs, due to the low kinetic stability of Gd-complex. We develop of manganese(III)

porphyrins (MnP) as alternative Gd-free contrast agents. Mn(III) porphyrins have higher

sensitivity under high magnetic field, higher stability and lower toxicity. One of the

designed porphyrins is MnTCP, the first MnP-based extracellular agent. Here we

investigate the stability of MnTCP under various conditions. We designed the

experimental conditions to test under different pH, temperature, chelate and metal ions.

We chose five different metals, zinc, copper, iron, calcium, and magnesium as possible

replacements of manganese in MnTCP and monitored for over two months.

Measurements were made using UV-Visible spectroscopy because porphyrins exhibit an

unique spectra with high intensity Soret band and low intensity Q bands. HPLC was

applied as supplementary method when necessary. Preliminary results show no

significant changes for MnTCP. No metal dissociation or transmetallation was observed

up to 10X the metal concentrations. However, decreases in the Soret band was

observed in all iron concentrations. There was no indication of trans-metallated

porphyrin signal but may be caused by precipitation of the porphyrin from solution. In

conclusion, we demonstrated the high stability and kinetic inertness of MnTCP.

128 - Synthesis and Characterization of Mn(I) Complexes

for Asymmetric Polar Bond Reduction

Max Olson1, Karl Demmans1, Robert H. Morris1


The catalytic and asymmetric reduction of ketones to produce enantiopure alcohols is of

great importance to the flavour, fragrance, and fine chemicals industries. Currently,

many of the most active catalysts for such transformations are based on expensive and

toxic platinum group metals. The Morris group has focused on the development

of asymmetric direct hydrogenation (ADH) and asymmetric transfer hydrogenation (ATH)

catalysts that incorporate cheap, earth-abundant, and non-toxic metals including iron,

cobalt, and manganese. Currently under development are a class of chiral

manganese(I) complexes incorporating the PNP tridentate pincer ligands seen in

previous reports by the Morris group on iron(II)-based hydrogenation catalysts.

Described herein are strategies for their synthesis and characterization as well

as preliminary results for their activity in transfer hydrogenation.

131 - Determining the Calcium Bound Structure of

Daptomycin

Nour Mashmoushi1, Ryan Moreira1, W. Scott Hopkins1


Daptomycin is a calcium-dependent cyclic lipopeptide used in treating infections caused

by gram-positive bacteria, including skin infections from methicillin-resistant and

vancomycin-resistant bacteria. Its bactericidal capacity is dependent on its binding to

calcium. While it is a relatively new drug, there have been documented cases of

nonsusceptibility to the antibiotic in patients. Since its 3D structure and action

mechanism are not yet well understood, finding ways to modify the lipopeptide to

prevent bacterial resistance is a difficult task. This research project aims at

experimentally and computationally identifying structural characteristics of the

daptomycin that help in binding calcium. Daptomycin can be modified at different amino

acid sites with different affinities to calcium and studied to understand calcium binding.

Using differential mobility spectrometry, daptomycin and its analogues are analyzed to

determine their clustering behavior and hence, structural conformations. In addition,

computational studies are performed to determine the most energetically-stable

conformers of the calcium-bound and unbound analogues in solution and gaseous

states. Calculations to determine the most favourable conformation of the calcium-bound

structure will provide a greater insight into the role of calcium in the action mode of

daptomycin will be acquired.

133 - Crystallization of a Putative Polysaccharide Lyase

TDE0626 from Treponema denticola

Vasu Patel1, Michael D. L. Suits1


The “red-complex” is a consortia of bacteria, consisting of Treponema

denticola, Tannerella forsythia, and Porphyromonas gingivalis, that are associated with

the progression of periodontitis. T. denticola produces virulence factors that facilitate

infection and tissue damage. The open reading frame TDE0626 from T. denticola was

identified to be up-regulated during dense co-culture via transcriptome analysis.

Bioinformatics analysis suggests TDE0626 to be a putative polysaccharide lyase

enzyme comprised of a parallel β-helix fold. Four crystallization conditions for TDE0626

have been identified using sitting drop and hanging drop protein crystallization methods.

Optimization of these conditions could lead to the production of diffraction-quality

crystals for structural determination. Characterizing the structure and function would aid

in elucidating the role of TDE0626 in T. denticola.

136 - Characterization of a GH88 Family Glucuronyl

Hydrolase from Tannerella forsythia

Peter Nguyen1, Dr. Michael Suits1

1Wilfird Laurier University

Polymicrobial complexes that cause periodontal disease form biofilms that make

treatment difficult. Tannerella forsythia is a member of the red complex; a group of

bacteria implicated with advanced periodontal disease. A number of virulence factors

are expressed by T. forsythia that aid in the proliferation of periodontal disease. One

such pathway degrades chondroitin sulfate A, a carbohydrate component of connective

tissue. Using fluorophore assisted carbohydrate electrophoresis, and bioinfomatics,

some functional characterization of BFO2285, a putative unsaturated glucuronyl

hydrolase was found to be inactive on sulfated chondroitin due to a lack of three

conserved residues on GH88 family hydrolases specific for sulfate group binding.

138 - Synthesis and Characterization of Novel Copper(I)

and Nickel(II) Complexes with a Tetradentate

Bis(amino)-Bis(N-heterocyclic carbene) (CNNC) ligand

Nina Farac1, Kai Yang Wan1, Elvira Bergen1, Robert H. Morris1


N-heterocyclic carbene (NHC) ligands have become known as a promising alternative to

phosphine ligand-based transition metal catalyzed processes as NHC ligands provide a

σ-donor strength comparable or greater than that of a phosphine with potentially less

toxic effects. An important application of NHC-metal complexes is in the field of

asymmetric catalysis, mainly asymmetric hydrogenation for the production of

enantiomerically pure alcohols and amines, which are essential intermediates in the

synthesis of pharmaceuticals, fragrances, and agrochemicals. Herein, a tetradentate

bis(amino)-bis(NHC) (CNNC) ligand – ‘a-a-CNNC’ – was prepared in high yield by a

simple Schiff base condensation between glyoxal solution and two equivalents of an

earlier reported enantiopure (S,S)-[Ph-Ph-KaibeneH]PF6 proligand rendering the

bis(imino) analog, which was then followed by a reduction with sodium borohydride to

give the desired bis(amino) form. This bis(amino)-bis(NHC) proligand, with the molecular

formula [(S,S,S,S)-H3C-NC3H3N-CHPhCHPh-NHCH2CH2NH-CHPhCHPh-NC3H3N-

CH3](PF6)2, when reacted with a slight excess of potassium bis(trimethylsilyl)amide,

produces the corresponding tetradentate NHC-NH-NH-NHC ligand (a-a-CNNC). In the

presence of copper(I) starting material CuI, a novel CuI(a-a-CNNC) complex can be

prepared and characterized by nuclear magnetic resonance spectroscopy (NMR) and

elemental analysis (EA). A novel nickel(II) complex was additionally prepared, [Ni(a-a-

CNNC)](PF6)2, but only partially characterized with NMR and requires further

purification.

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