Inorganic Reaction Mechanisms & Inorganic Biochemistry Discussion Group Meeting

Joint Meeting at the Manchester Institute of Biotechnology from the 15th

to 17th

of April (2019)

Venue: MIB Lecture Theatre, John Garside Building, 131 Princess Street, Manchester, M1 7DN

Abstracts:

Award Lecture:

AL: Award Lecture: Stephen Mann (Bristol, UK)

Plenary talks:

PL1: Plenary talk 1: Christine McKenzie (Odense, Denmark)

PL2: Plenary talk 2: Francesca Paradisi (Nottingham, UK)

PL3: Plenary talk 3: Miquel Costas (Girona, Spain)

Oral presentations:

OL1: Oral presentation 1: Sara Kyne (Lincoln, UK)

OL2: Oral presentation 2: James Walton (Durham, UK)

OL3: Oral presentation 3: Jonathan Worrall (Essex, UK)

OL4: Oral presentation 4: Marta Chrzanowska (Toruń, Poland)

OL5: Oral presentation 5: Luisa Ciano (York, UK)

OL6: Oral presentation 6: Callum R. Woof (Bath, UK)

OL7: Oral presentation 7: M. Qadri E. Mubarak (Manchester, UK)

OL8: Oral presentation 8: Lisa Miller (University of York, York, UK)

OL9: Oral presentation 9: Samuel M. Neale (Heriot Watt University, Edinburgh, UK)

OL10: Oral presentation 10: Aidan McDonald (Trinity College Dublin, Dublin, Ireland)

OL11: Oral presentation 11: Sophie Bennett (University of East Anglia, Norwich, UK)

OL12: Oral presentation 12: Danila Gasperini (University of Bath, Bath, UK)

OL13: Oral presentation 13: Jason Lynam (University of York, York, UK)

OL14: Oral presentation 14: Justin Bradley (University of East Anglia, Norwich, UK)

OL15: Oral presentation 15: Galvin Leung (University of Leicester, Leicester, UK)

OL16: Oral presentation 16: Charlène Esmieu (University of Toulouse, Toulouse, France)

OL17: Oral presentation 17: Hazel Girvan (University of Manchester, Manchester, UK)

OL18: Oral presentation 18: Megan Greaves (University of Strathclyde, Glasgow, UK)

OL19: Oral presentation 19: Amanda Jarvis (University of Edinburgh, Edinburgh, UK)

OL20: Oral presentation 20: Ulrich Hintermair (University of Bath, Bath, UK)

OL21: Oral presentation 21: Sophie Kendall-Price (University of Oxford, Oxford, UK)

Posters:

P1: Felicia Ejia (University of Lagos, Lagos, Nigeria)

P2: Melissa Stewart (University of East Anglia, Norwich, UK)

P3: Marta Chrzanowska (Copernicus University, Toruń, Poland)

P4: Manel Martínez (University of Barcelona, Barcelona, Spain)

P5: Niting Zeng (University of Manchester, Manchester, UK)

P6: Yen-Ting Lin (University of Manchester, Manchester, UK)

P7: Miron Leanca (University of Manchester, Manchester, UK)

P8: Alex Miller (Liverpool John Moores University, Liverpool, UK)

P9: Emilie F. Gérard (University of Manchester, Manchester, UK)

P10: Adam Barrett (University of Bath, Bath, UK)

P11: Oliver Manners (University of Manchester, Manchester, UK)

P12: David McLaughlin (University College Dublin, Dublin, Ireland)

P13: Mary Ortmayer (University of Manchester, Manchester, UK)

P14: Mads Sondrup Møller (University of Southern Denmark, Odense, Denmark)

P15: Line Sofie Hansen (University of Southern Denmark, Odense, Denmark)

P16: Tobias Hedison (University of Manchester, Manchester, UK)

P17: Arron Burnage (Heriot-Watt University, Edinburgh, UK)

P18: Amirah Kamaruddin (University of Manchester, Manchester, UK)

P19: Sidra Ghafoor (Government College University, Faisalabad, Pakistan)

P20: Sangita Das (Durham University, Durham, UK)

P21: David Collison (University of Manchester, Manchester, UK)

P22: Sultan Alkaabi (University of Manchester, Manchester, UK)

AL: Award Lecture: Stephen Mann (Bristol)

Synthetic protobiology: the chemistry of life-like objects

Stephen Mann

Centre for Protolife Research, Centre for Organized Matter Chemistry, School of Chemistry

University of Bristol, Bristol BS8 1TS, UK. E-mail: S.Mann@bristol.ac.uk

Recent progress in the chemical construction of micro-compartmentalized semipermeable colloidal objects

comprising integrated biomimetic functions is paving the way towards rudimentary forms of artificial cell-like

entities (protocells) for modelling complex biological systems, exploring the origin of life, and advancing future

proto-living technologies. Although several new types of protocells are currently available, the design of

synthetic protocell communities and investigation of their collective properties has received little attention. In

this talk, I review some recent experiments undertaken in my laboratory that demonstrate simple forms of

higher-order dynamic behaviour in synthetic protocells. I will discuss four new areas of investigation: (i)

enzyme-powered motility and collective migration in buoyant organoclay/DNA protocells,1 (ii) artificial

predatory, phagocytosis and endosymbiosis behaviour in mixed populations of synthetic protocells,2,3,4 (iii)

chemical communication and DNA computing in ordered protocell communities,5 and (iv) the chemical

construction of beating prototissues.6 I will use these new model systems to discuss pathways towards chemical

cognition, modulated reactivity, basic signalling pathways and non-equilibrium activation in compartmentalized

artificial micro-ensembles.

References

[1] Kumar, P. B. V. V. S.; Patil, A. J.; Mann, S. Enzyme-powered motility in buoyant organoclay/DNA

protocells. Nature Chemistry 2018, 10, 1154-1163.

[2] Qiao, Y.; Li, M.; Booth, R.; Mann, S. Predatory behaviour in synthetic protocell communities. Nature

Chemistry 2017, 9, 110–119.

[3] Rodríguez-Arco, L.; Li, M.; Mann, S. Artificial phagocytosis in synthetic protocell communities of

compartmentalized colloidal objects. Nature Materials 2017, 16, 857-863.

[4] Martin, N.; Douliez, J.-P.; Qiao, Y.; Booth, R.; Li, M.; Mann, S. Antagonistic chemical coupling in self-

reconfigurable host-guest protocells. Nature Communications 2018, 9, 3652.

[5] Joesaar. A.; et al; Distributed DNA-based communication in populations of synthetic protocells. Nature

Nanotechnology 2019 DOI: 1038/s41565-019-0399-9.

[6] Gobbo, P.; Patil, A. J.; Li, M.; Mann, S. Programmed assembly of synthetic protocells into contractile

prototissues. Nature Materials 2018, 17, 1145-1153.

PL1: Plenary talk 1: Christine McKenzie (Odense, Denmark)

A Janus-faced Iron Catalyst

Christine J. McKenzie

Department of Physics, Chemistry and Pharmacy, University of Southern Denmark,

Campusvej 55, 5230 Odense M, Denmark. E-mail: mckenzie@sdu.dk

Through solvent-dependent coordinative flexibility, the iron(III) complex of N,N,N′-tris(2-pyridylmethyl)-

ethylenediamine-N′-acetate (tpena) can catalyze the oxidation of organic substrates through either H-atom

abstraction, or, at the other end of the reactivity scale, selective oxygenation. These reactivity extremes give

mechanistic hints for the development of

new greener methodologies for catalyzing

oxidation reactions in the divergent fields

of water remediation and fine chemical

synthesis. In water, the oxidation of

dissolved organic compounds by

peroxides[1]

or hypochlorite as the

terminal chemical oxidant can be

catalyzed by [Fe(tpena)]2+

. More

intriguing however, is that

electrocatalytic oxidation - where water is

part of the atom balance - can be applied

for the total mineralization of trace

organic pollutants, without competition

from energy-consuming water oxidation

(figure, top).[2]

The mechanism involves

one-electron steps to allow cycling

between the resting state iron(III) and an iron(IV)oxo species with a comparatively high oxyl radical character.

In non-protic solvents, [Fe(tpena)]2+

mobilizes the practical, but highly insoluble polymeric oxidant,

“hypervalent” iodosylbenzene, [PhIO]n.[3]

An intermediate in the reaction is an unique FeIII

-OIPh complex.[4]

For

this mechanism we propose that the iron retains the +3 oxidation state throughout the catalytic cycle (figure,

bottom). Water, excess PhIO, or darkness, protect the supporting tpena itself from oxidative decomposition. In

their absence, the O2- and iron-dependent oxidation of tpena is triggered by sunlight. This reaction models iron

mobilization by, e.g., siderophores.[5]

[1] C. Wegeberg, W. R. Browne and C. J. McKenzie, ACS Catalysis, 2018, 8, 9980–9991; C. Wegeberg, F. R.

Lauritsen, C. Frandsen, S. Mørup, W. R. Browne, C. J. McKenzie, Chem., A Eur. J. 2018, 24, 5134-5145.

[2] D. P. de Sousa, C. J. Miller, Y. Chang, T. D. Waite, C. J. McKenzie, Inorg. Chem., 2017, 56, 14936–14947.

[3] C. Wegeberg, C. G. Frankær and C. J. McKenzie, Dalton Trans, 2016, 45, 17714-17722.

[4] A. Lennartson and C. J. McKenzie, Angew. Chem., Int. Ed., 2012, 51, 6767-6770; D. P. de Sousa, C.

Wegeberg, M. V. Sørensen, S. Mørup, C. Frandsen, W. A. Donald and C. J. McKenzie, Chem, Eur. J. 2016,

22, 3521–3890.

[5] C. Wegeberg, V. M. Fernández-Alvarez, A. de Aguirre, C. Frandsen, W. R. Browne, F. Maseras and C. J.

McKenzie, J. Am. Chem. Soc., 2018, 140, 14150–14160.

PL2: Plenary talk 2: Francesca Paradisi (Nottingham)

Carbene ligand to replace histidine in cupredoxin protein scaffolds

Francesca Paradisi

Department of Chemistry, University of Nottingham,

University Park, Nottingham NG7 2RD, United Kingdom. E-mail: Francesca.Paradisi@nottingham.ac.uk

N-heterocyclic carbene (NHC) ligands have had a major impact in homogeneous catalysis, however, their

potential role in biological systems is essentially unexplored. We initially replaced a copper-coordinating

histidine (His) in the active site of the electron shuttle protein azurin with exogenous dimethyl imidazolylidene.

This NHC rapidly restores the type-1 Cu center, with spectroscopic properties (EPR, UV/Vis) that are identical

to those from N-coordination of the His in the wild type. However, the introduction of the NHC markedly alters

the redox potential of the metal, which is a key functionality of this blue copper protein. Following these

experiments, we also probed the role of NHC in a catalytically active enzyme containing the same copper centre

(nitrite reductase) which significantly enhanced its activity with respect with the aqua variant. These results

suggest that C-bonding for histidine is plausible and a potentially relevant bonding mode of redox-active

metalloenzymes in their (transient) active states.

PL3: Plenary talk 3: Miquel Costas (Girona, Spain)

FeV complexes of relevance in enzymology and organic synthesis

Miquel Costas

Institut de Química Computacional I Catàlisi, Universitat de Girona, Facultat de Ciències, Campus de

Montilivi, 17003, Girona, Spain. e-mail: Miquel.costas@udg.edu

High-valent iron compounds are very reactive species that are involved in a number of reactions of interest in

biology, chemical synthesis and technology.[1-4]

For instance high-valent iron-oxo species are key intermediates

in challenging oxidation reactions such as C-H and C=C oxidation[2-3]

and water oxidation,[5]

and high-valent

nitride and related species have been considered as possible intermediates in iron-mediated dinitrogen reduction

to ammonia.[6-7]

The high reactivity of these species makes their preparation and characterization a very challenging

task. In the current contribution we will describe the generation and spectroscopic characterization of

exceedingly reactive non porphyrinic Fe(V) species with terminal oxo ligands. Their involvement in C-H and

C=C functionalization, and O-O bond formation reactions will be discussed.[8]

References

[1] McDonald, A. R.; Que, L., Jr. Coord. Chem. Rev. 2013, 257, 414.

[2] Groves, J. T. J. Inorg. Biochem. 2006, 100, 434.

[3] Hohenberger, J.; Ray, K.; Meyer, K. Nat. Commun. 2012, 3, 720.

[4] Nam, W.; Lee, Y.-M.; Fukuzumi, S. Acc. Chem. Res. 2014, 47, 1146.

[5] Fillol, J. L.; Codolà, Z.; Garcia-Bosch, I.; Gómez, L.; Pla, J. J.; Costas, M. Nat. Chem. 2011, 3, 807-13.

[6] Rittle, J.; Green, M. T. Science 2010, 330, 933.

[7] Scepaniak, J. J.; Vogel, C. S.; Khusniyarov, M. M.; Heinemann, F. W.; Meyer, K.; Smith, J. M. Science

2011, 331, 1049.

[8] a) Fan et al. J. Am. Chem. Soc. 2018, 140, 3916. b) Borrell et al. Nat. Commun. 2019, in press

OL1: Oral presentation 1: Sara Kyne (Lincoln, UK)

Mechanistic studies of radical reactions: Improving efficiency of chain

processes

Sara Kyne

University of Lincoln, United Kingdom.

e-mail: skyne@lincoln.ac.uk

Radical chemistry is a powerful and versatile tool for synthetic chemistry. Single electron transfer processes

offer complimentary reactivity to two-electron or polar reactions, due to the open shell reactive species that

undergo chemical reaction through otherwise difficult to access pathways. The use of radical chemistry in

synthesis has become more prevalent in part due to the application of transition metal coordination compounds

as photocatalysts for generating organic radicals. Visible light mediated photoredox catalysis has given rise to a

wide variety of new synthetic processes including late stage functionalisation, carbon-carbon and carbon-

heteroatom bond formation reactions.[1]

In some instances, such as that below, excellent but unexpected chemoselectivity has been achieved (below).[2]

This approach could potentially be used to selectively modify unprotected carbohydrates, if the reaction could

be better understood. Ultimately, to design and execute new complex photoredox catalytic reactions, it is critical

to elucidate the photochemical mechanism of reaction.[3]

In particular, it is important to determine the origin of

chemo- and regio-selectivity of photoredox reactions, which this talk will seek to address.

References

[1] M. H. Shaw, J. Twilton, D. W. C. MacMillan, J. Org. Chem. 2016, 81, 6898-6926.

[2] I. C. S. Wan, M. D. Witte, A. J. Minnaard, Chem. Commun. 2017, 53, 4926–4929.

[3] M. Marchini, G. Bergamini, P. G. Cozzi, P. Ceroni, V. Balzani, Angew. Chem. Int. Ed. 2017, 56, 12820–

12821.

O

O

OH

HO

OHHO

O

O

OH

HO

OHOH

PhO2S

SO2Ph

1 mol% [Ir] cat10 mol% Quinuclidine25 mol% Bu4NH2PO4

DMSO, Blue LED16 h

OL2: Oral presentation 2: James Walton (Durham, UK)

Catalytic reaction of organometallic ruthenium complexes

James W. Walton, Jack. A. Pike, Luke A. Wilkinson, Luke Williams, David Bradley

Durham University, United Kingdom.

e-mail: james.walton@durham.ac.uk

η6-Coordination of aromatic molecules to transition metals alters the reactivity of the bound arene. Typically

this η6-coordination will increase the electrophilicity of the arene and stabilise negatively charged reaction

intermediates. Since beginning our independent research group in 2014, we have been studying reactions of [(η6

arene)RuCp]+ complexes. We will present successful SNAr,

[1] C‒H activation

[2] and trifluoromethylation

[3]

reactions based on the mechanism shown below.

While η6-coordination gives access to exciting new reaction of arenes, the requirement for stoichiometric metal

is a drawback. To address this issue, our research also focusses on reactions that are catalytic in the activating

metal fragment. Following reaction of η6-bound arenes, exchange between the bound product and starting

material will lead to catalytic systems (Figure). To achieve this, we need an understanding of the mechanism of

arene exchange. We have recently reported a catalytic SNAr process[1]

and have shown that C‒H activation[2]

and trifluoromethylation[3]

can proceed with recovery of the activating Ru fragment. This research has great

potential to allow late-stage modification of arenes for application in drug discovery, as well as developing

fundamental understanding of organometallic Ru complexes.

References

[1] Walton, J. W.; Williams, J. M. J. Chem. Commun., 2015, 51, 2786

[2] Wilkinson, L. A.; Pike, J. A.; Walton, J. W. Organometallics, 2017, 36, 4376.

[3] Pike, J. A.; Walton, J. W. Chem Commun., 2017, 53, 9858.

OL3: Oral presentation 3: Jonathan Worrall (Essex, UK)

An aromatic dyad motif in dye decolorizing peroxidases has implications

for free radical formation and catalysis

Amanda K. Chaplin, Tadeo Moreno Chicano, Bethany V. Hampshire, Michael T. Wilson,

Michael A. Hough, Dimitri A. Svistunenko, Jonathan A.R. Worrall

School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester, CO4 3SQ, UK., United

Kingdom.

e-mail: jworrall@essex.ac.uk

Dye decolouring peroxidases (DyPs) are the most recent class of heme peroxidase to be discovered. On reacting

with H2O2 DyPs form a high-valent iron(IV)-oxo species and a porphyrin radical (Compound I) followed by

stepwise oxidation of an organic substrate. In the absence of substrate, the reactive ferryl species decays to form

transient protein-bound radicals on redox active amino acids. Identification of radical sites in DyPs has

implications for their oxidative mechanism with substrate, but this phenomenon is not well understood. Using a

DyP from Streptomyces lividans, referred to as DtpA, which displays low reactivity towards synthetic dyes,

activation with H2O2 was explored. A Compound I EPR spectrum is detected, which in the absence of substrate

decays to a protein-bound radical EPR signal. Using a newly developed version of our Tyrosyl Radical Spectra

Simulation Algorithm, we show that the radical EPR signal arises from a pristine tyrosyl radical and not a mixed

Trp/Tyr radical that has been widely reported in DyP members exhibiting high activity with synthetic dyes. The

radical site is identified as Tyr374, with kinetic studies inferring that Tyr374 is not important for oxidation of

the dye RB19, but does severely compromise activity with other organic substrates. Our findings hint at the

possibility that different electron transfer pathways for substrate oxidation are operative within DyP members

with a role for a highly conserved aromatic dyad motif discussed.

OL4: Oral presentation 4: Marta Chrzanowska (Toruń, Poland)

Substitution behaviour and tuning of [RuII(terpy)(N^N)X]

+/2+ complexes

M. Chrzanowska,a A. Katafias,

a R. van Eldik

a,b

a Faculty of Chemistry, N. Copernicus University, Gagarina 7, 87-100 Toruń, Poland

b Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland

e-mail: katafias@umk.pl

Over the past few years we have been engaged in studies on the aqueous chemistry of [RuII(terpy)(N^N)X]

+/2+

type complexes, where terpy, N^N and X represent 2,2’:6’,2’’-terpyridine, N^N-donor bidentate ligands, and Cl-

or H2O, respectively.[1,2]

Our main goal was to gain insight into the tuning of the reactivity of such species, i.e.

the lability of their monodentate ligand X that could be of biological relevance. Since the nature of the spectator

chelates has a pronounced effect on the stability and in general on the aqueous behaviour of such species, we

examined a series of four complexes with N^N chelates of varying electronic effects, i.e. 1,10-phenantroline

(phen), 2,2’-bipyridine (bipy), 2-(aminomethyl)pyridine (ampy) and ethylenediamine (en). Our studies showed

that the rates of both the spontaneous aquation of the parent chlorido complexes, pKa values and substitution of

the coordinated water molecule in the corresponding aqua species by chloride, thiourea and N,N’-

dimethylthiourea, decrease in the order: [RuII(terpy)(en)X]

+/2+ >> [Ru

II(terpy)(ampy)X]

+/2+ >

[RuII(terpy)(bipy)X]

+/2+ ~ [Ru

II(terpy)(phen)X]

+/2+. This can be accounted for by a decrease in electron density

on the metal center due to a systematic increase in the -acceptor properties of the N^N spectator ligands. The

resulting stronger coordination of the X ligand lowers the lability of the [RuII(terpy)(N^N)X]

+/2+ complexes in

substitution reactions and increases the acidity of their aqua derivatives. Such opposite mechanistic findings

were reported before for square-planar Pt(II) and Pd(II) complexes, but never for octahedral Ru(II) complexes. [3]

References

[1] M. Chrzanowska, A. Katafias, O. Impert, A. Kozakiewicz, A. Surdykowski, P. Brzozowska, A. Franke, A.

Zahl, R. Puchta, R. van Eldik, Dalton Trans., 2017, 46, 10264.

[2] M. Chrzanowska, A. Katafias, A. Kozakiewicz, R. Puchta, R. van Eldik, J. Coord. Chem., 2018, 71, 1761.

[3] (a) D. Jaganyi, D. Reddy, J.A. Gertenbach, A. Hofmann, R. van Eldik, Dalton Trans., 2004, 299; (b) B.

Petrovic, Z.D. Bugarcic, A. Dees, I. Ivanovic-Burmazovic, F.W. Heinemann, R. Puchta, S.N. Steimann, C.

Corminboeuf, R. van Eldik, Inorg. Chem., 2012, 51, 1516.

OL5: Oral presentation 5: Luisa Ciano (York, UK)

The molecular basis of polysaccharide cleavage by in lytic polysaccharide

monooxygenases

L. Ciano,1,2

G. J. Davies1 and P. H. Walton

1

1 Department of Chemistry, University of York, YO10 5DD, York, United Kingdom;

2 Current address: EPSRC National EPR Facility and Service, School of Chemistry, University of Manchester,

Oxford Road, M13 9PL, Manchester, United Kingdom.

e-mail: luisa.ciano@manchester.ac.uk

The effective use of biomass is crucial in addressing the global need for sustainable energy sources. However,

polysaccharides are highly recalcitrant to degradation, which poses a major challenge in their utilisation for the

production of biofuel and commodity chemicals from renewable sources. A major breakthrough in the field was

achieved by the discovery of a new class of enzymes called lytic polysaccharide monooxygenases (LPMOs),

copper-depending enzymes found in a variety of organisms.[1,2]

LPMOs break down polysaccharide chains via

an oxidative mechanism in the presence of a reducing agent and molecular oxygen, thus boosting the action of

classic enzymatic cocktails for industrial polysaccharide degradation.

Understanding the mechanism of action of these enzymes and their interaction with the substrate is essential for

the development of this field. Comprehensive structural, kinetic and spectroscopic investigations of an

oligosaccharide-active LPMO from the AA9 family have recently been reported,[3,4]

giving the first insight into

the changes caused by the arrival of substrate to the Cu active site of the enzyme. In conjunction with solution

kinetic measurements and crystallographic studies, we carried out a detailed electron paramagnetic resonance

spectroscopy (EPR) investigation, which reveals key interactions in the active site of the enzyme upon addition

of substrate (Figure 1). Furthermore, 1H HYSCORE experiments in the presence of cellohexaose and chloride

demonstrated the involvement of the N-terminus in a hydrogen bond network which ‘connects’ the copper

active site to the oligosaccharide via a ‘pocket’ water molecule.[3]

Electron paramagnetic resonance (EPR)

spectroscopy studies revealed differences in Cu-coordination upon binding of glucans and xylan.[4]

We have

now furthered these studies by analysing the interaction between the LPMO and its natural crystalline substrate

through the development of a semi-oriented EPR spectroscopy method. In this talk we will highlight these

collective data in LPMO chemistry and the implications for their effective utilisation in biomass degradation.

Left - EPR of the LPMO before (bottom) and after (top) addition of substrate; Middle - Scheme of key

interactions between substrate and Cu active site; Right - Crystal structure in the presence of substrate (PBD:

5ACI)

References

[1] R.J. Quinlan et al. Proc. Natl. Acad. Sci. USA 2011, 108,15079.

[2] G. Vaaje-Kolstad et al. Science 2010, 330, 219.

[3] K.E.H. Frandsen et al. Nature Chem. Biol. 2016, 12, 298.

[4] T.J. Simmons et al. Nature Commun. 2017, doi:10.1038/s41467-017-01247-3.

OL6: Oral presentation 6: Callum R. Woof (Bath, UK)

Iron-Catalysed Isomerisation of Alkenes – Exploring Reactivity &

Mechanism through Synthesis, Spectroscopy & DFT

Callum R. Woof,a Craig P. Butts,

b Derek J Durand,

b Natalie Fey,

b Emma Richards,

c Ruth L.

Webstera

a Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, United Kingdom b School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, United Kingdom

c School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, United Kingdom.

e-mail: cw591@bath.ac.uk

Iron has been touted as a sustainable and non-toxic alternative to many precious metals in catalytic processes.

One field of particularly high interest has been functionalization of alkenes, with numerous reports of

hydroamination,[1]

hydroboration[2]

and hydrophosphination[3]

reactions. There has, however, been relatively

little work on catalytic alkene isomerisation, and contemporary work, for example by von Wangelin,[4]

often

requires stoichiometric reducing agents to proceed.

Using a catalytic amount of borane, we can activate tuneable ß-diketiminate iron(II) pre-catalysts and isomerise

allyl-based substrates to more valuable products, which are relevant to the fragrance and specialised chemical

industries. Furthermore, we can apply this reactivity to linear alkenes such as 1-hexene. We observe divergent

reactivity depending on the borane used (e.g. pinacolborane vs. ammonia borane) and have attempted to

rationalise this observation amongst others with a variety of techniques. This includes monitoring reactions in

situ using NMR and EPR spectroscopy, developing synthetic approaches to probe catalytic behaviour and using

computational methods to postulate a catalytic cycle. Both the synthetic scope and our current mechanistic

insight to this transformation will be presented.

References

[1] L. J. Gooßen et.al. Chem. Rev., 2015, 115, 2596–2697.

[2] H. J. Knölker et.al. Chem. Rev., 2015, 115, 3170–3387.

[3] S. H. Chikkali et.al. Coord. Chem. Rev., 2014, 265, 52–73.

[4] A. J. von Wangelin et.al. ChemCatChem, 2011, 3, 1567–1571.

OL7: Oral presentation 7: M. Qadri E. Mubarak (Manchester, UK)

Computational modelling on the mechanism of vanadium haloperoxidases

M. Qadri E. Mubarak and Sam P. de Visser

The Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, The

University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom.

e-mail: muhammadqadri.mubarak@postgrad.manchester.ac.uk

There is still a lot to learn from nature, including the mechanism of chemical transformations, which then can be

utilize and improved in biotechnological aspects to suit our needs. Thus, in biocatalysis we aim to gain

important information on chemical reaction mechanisms. However, as experimental work is often challenging

due to short-lived intermediates, we have embarked on a computational study instead. Vanadium dependent

haloperoxidases (VHPO) abundantly exist in the marine environment and are thought to be responsible for the

biosynthesis of halogenated natural products. These enzymes efficiently catalyze the oxidation of higher halides

X‒ (Cl

‒, Br

‒) to the corresponding hypohalous acids (HOX), with hydrogen peroxide as an oxygen source. The

controlled partial oxidation of such substrates to well-defined products is potentially very useful for humankind.

Despite the remarkable importance in technical oxidation, deep study on VHPO biocatalysis mechanism to the

best of our knowledge has never been reported, despite the ability of the VHPO to form peroxy complexes.

Quantum chemical study on VHPO enzymes and focus on the catalytic cycle that converts hydrogen peroxide

into hypochloride.

OL8: Oral presentation 8: Lisa Miller (University of York, York, UK)

Antibiotic-functionalised surfaces for the detection of β-lactamases

Lisa M. Miller, Callum D. Silver, Anne-Kathrin Duhme-Klair, Gavin Thomas, Thomas F.

Krauss, and Steven Johnson

University of York, Heslington, York, YO10 5DD, United Kingdom. e-mail: lisa.miller@york.ac.uk

Antimicrobial resistance (AMR) is a major threat to public health worldwide. This work is part of the

Multiparameter Assay for Profiling Susceptibility (MAPS) project, which is focused on the development of a

novel devices for the detection of AMR, to aid clinicians in the fight against bacterial infections.

One of the more prevalent mechanisms that bacteria have developed to resist antibiotics are the β-lactamase

enzymes, which catalytically deactivate β-lactam drugs such as penicillin and amoxicillin. At the heart of our

devices are sensors designed to change in the presence of antibiotic resistant bacteria. I would like to share the

chemistry that has gone into the design and development of functionalised Au and SiO2 surfaces, as well as our

progress in the application of these surfaces for the detection of β-lactamases in complex biological media, such

are urine.

The MAPS team is an interdisciplinary collaboration between the biology, chemistry, physics, and electronics

departments at the University of York. Our goal is to provide a fast and reliable tool for diagnosis, to ensure an

effective treatment is prescribed to patients before the infection can develop further. We hope to identify other

researchers who could provide valuable collaborations and help us conquer the challenges that we are currently

facing in this work.

OL9: Oral presentation 9: Samuel M. Neale (Heriot Watt University, Edinburgh, UK)

Mechanistic studies into iron-catalysed transfer hydrogenation using

amines and boranes

Samuel E. Neale,1 Maialen Espinal-Viguri,

2 Nathan T. Coles,

2 Ruth L. Webster,

2 and Stuart

A. Macgregor1

1 Institute of Chemical Sciences, Heriot Watt University, Edinburgh EH14 4AS, United Kingdom;

2 Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom.

e-mail: sen1@hw.ac.uk

High-First row transition metal complexes featuring β-diketiminate ligands have recently emerged as promising

catalysts for a range of organic transformations.[1]

For example, we have recently demonstrated the use of a β-

diketiminatoiron(II) catalyst for the mild and rapid transfer hydrogenation of a range of unactivated alkenes,

using a combination of an amine and HBpin as transfer reagents.[2]

This strategy can also be used to effect the

regioselective deuteration at each of the alkene carbons, depending on the choice of the deuterated transfer

reagent.

Here we present the results of density functional theory (DFT) calculations combined with experimental data to

characterise the mechanism for this transfer hydrogenation process. Key to understanding the selectivity were

the kinetics of a spin-accelerated alkene-insertion at a hydrido-iron(II) intermediate.[3]

Experimentally, a thick gel was observed in the catalysis upon addition of HBpin to the reaction mixture, and

this is proposed to be a polymeric H-bonded amine-borane adduct, [HBpin•H2NPh]n. Modelling this with

dimeric [HBpin•H2NPh]2 in the calculations proved crucial in order to understand the dominance of alkene

transfer hydrogenation over potentially competing processes such as amine-borane dehydrocoupling and alkene

hydroboration.

References

[1] R. L. Webster, Dalton Trans. 2017, 46, 4483-4498.

[2] M. Espinal-Viguri, S. E. Neale, N. T. Coles, S. A. Macgregor, and R. L. Webster, J. Am. Chem. Soc., 2019,

141, 572-582.

[3] S. M. Bellows, T. R. Cundari, P. L. Holland, Organometallics. 2013, 32, 4741-4751.

OL10: Oral presentation 10: Aidan McDonald (Trinity College Dublin, Dublin, Ireland)

Mimicking class Ib Mn2-ribonucleotide reductase: MnII

2 complexes and

their reaction with superoxide

Adriana M. Magherusan,a Ang Zhou,

b Erik R. Farquhar,

c Max García-Melchor,

a Brendan

Twamley,a Lawrence Que, Jr.,

b Aidan R. McDonald

a

a School of Chemistry and CRANN/AMBER Nanoscience Institute, Trinity College Dublin, The University of

Dublin, College Green, Dublin 2, Ireland b Department of Chemistry and Centre for Metals in Biocatalysis, University of Minnesota, 207 Pleasant St. SE,

Minneapolis, MN 55455, USA c Case Western Reserve University Centre for Synchrotron Biosciences, National Synchrotron Light Source II,

Brookhaven National Laboratory, Upton, NY 11973, USA.

e-mail: aidan.mcdonald@tcd.ie

A fascinating discovery in ribonucleotide reductase’s (RNRs) Chemistry has been the identification of a

dimanganese (Mn2) active site in class Ib RNRs that requires superoxide anion (O2•–

), rather than dioxygen (O2),

to access a high-valent Mn2 oxidant. [Mn2(O2CCH3)(N-Et-HPTB)](ClO4)2 (N-Et-HPTB = N,N,N’,N’-tetrakis(2-

(1-ethylbenzimidazolyl))-2-hydroxy-1,3-diaminopropane) was synthesised and reacted with O2•–

at -40 °C

resulting in the formation of a metastable species which displayed electronic absorption features (λmax = 460,

610 nm) typical of a Mn-peroxide species, and a 29 line EPR signal typical of a MnIIMn

III entity. We determined

that this was the first example of a MnIIMn

III-peroxide complex. It was capable of oxidizing ferrocene and weak

O–H bonds upon activation with proton donors following the mechanism proposed for the analogous

biochemical peroxide species. A second example of MnIIMn

III-peroxide complex was recently prepared and it

was found to react as a nucleophilic oxidant in aldehyde deformylation. Our findings provide support for the

postulated mechanism of O2•–

activation at class Ib Mn2 RNRs.

Reference Adriana M. Magherusan, Ang Zhou, Erik R. Farquhar, Max García-Melchor, Brendan Twamley, Lawrence Que,

Jr., Aidan R. McDonald, Angew. Chem. Int. Ed. 2017, DOI: 10.1002/anie.201709806

OL11: Oral presentation 11: Sophie Bennett (University of East Anglia, Norwich, UK)

Copper centre biogenesis in the nitrous oxide reductase of Paracoccus

denitrificans

Sophie P. Bennett,1 Manuel J. Soriano-Laguna,

2 David J. Richardson,

2 Andrew J. Gates

2 and

Nick E. Le Brun1

1 Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich

Research Park, Norwich, NR4 7TJ, United Kingdom 2 Centre for Molecular and Structural Biochemistry, School of Biological Sciences, University of East Anglia,

Norwich Research Park, Norwich, NR4 7TJ, United Kingdom

e-mail: Sophie.Bennett@uea.ac.uk

Agricultural practices have presented large amounts of anthropogenic nitrogen to soil microbes over the past

century, which has led to a significant rise in the emission of nitrous oxide (N2O), a potent ozone depleting and

greenhouse gas. The α-proteobacterium Paracoccus denitrificans (PD1222) can use these nitrogen species as

alternative electron acceptors under anaerobic conditions to survive, reducing nitrate stepwise to nitrogen gas in

the process known as denitrification. The final step, yielding N2 from N2O, is catalysed by N2OR, a homo

dimeric multi-copper enzyme with 2 copper cofactor centres: the CuA electron entry site similar to that of

cytochrome c oxidase, and the CuZ site, a unique [4Cu-2S] cluster.[1]

Copper deficiency leads to a loss of N2OR

catalytic activity and thus emission of N2O.[2]

Understanding how the copper metal centres of N2OR are

assembled and the effect of copper on organisms that require this metal is an essential pre-requisite for efforts

towards mitigating N2O emissions.

An investigation of the role of the accessory gene nosL in the nos gene cluster reveals that it is required for N2O

reduction under Cu limitation in P. denitrificans. N2OR purified from the ΔnosL mutant background exhibited

spectroscopic features characteristic of N2OR with a reduced copper content and with a lower N2OR activity

than the protein purified from the wild type background.

Studies of NosL heterologously expressed in E. coli demonstrated the ability of NosL to specifically bind Cu(I)

with high affinity. Together this work suggests a role for NosL as a copper binding protein involved in the

biogenesis of N2OR copper centres.

References [1] A. Pomowski et al, Nature 2011, 477, 234-238.

[2] M.J. Sullivan et al, Proc. Natl. Acad. Sci. USA 2013, 49, 19926-19931.

OL12: Oral presentation 12: Danila Gasperini (University of Bath, Bath, UK)

Seeking heteroatom rich compounds; iron catalysed efficient

heterodehydrocoupling of N-Si bond followed by desilacoupling to N-B

linkages

Andrew K. King,a Danila Gasperini,

a Samuel E. Neal,

b Stuart A. Macgregor,

b and Ruth L.

Webstera

a Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY, United Kingdom,

b Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom.

e-mail: dg686@bath.ac.uk

The catalytic construction of homonuclear E-E and heteronuclear E-E’ (E, E’ = B, Si, Ge, N, P, As) bonds have

been intensely investigated in the last decade.[1]

In particular the interest in N-Si and N-B bond formation has

increased in value, due to their application as valuable main group molecules and materials, such as polymers,

ceramics and their synthesis through catalytic dehydrocoupling methodologies have been exploited.[2]

Iron has

proven to have a prominent role among catalysts able to perform heterodehydrocoupling due to the metal’s

renowned low toxicity, natural abundance and low-cost. In this context, the use of well-defined three-coordinate

iron(II) β-diketiminates complexes have been successfully used by the Webster group for dehydrocoupling of

phosphine and amine-boranes,[3]

together with hydrofunctionalization and recently transfer hydrogenation of

unsaturated substrates.[4]

Therefore, seeking for novel and for improving existing catalytic processes, a one-pot

dehydrocoupling of amine and silanes to silazanes, followed by desilacoupling to amine-borane catalysed by

iron pre-catalyst 1 is herein disclosed.

Only 5 mol% of 1 are needed to fully convert secondary and primary amines with substituted alkyl and aryl

silanes, through H2 release. After full conversion to silazanes, the prompt addition of a stoichiometric amount of

pinacol borane released the silane in situ, while forming selectively N-B bonds. The desilacoupling reaction was

of particular interest due to the scarce literature precedence, and harsher conditions utilised in previous

methodologies with typically longer reaction times and reflux temperatures.[5]

Notably the reaction conditions

employed in the present work are mild, typically performed at room temperature, from 15 min to overnight. Fast

reaction rates are observed when starting from primary amines, while few limitations concerned silanes.

Furthermore, kinetic and computational analysis of the reaction mechanism were performed in order to elucidate

the sequential mechanism following pre-catalyst activation, dehydrocoupling and desilacoupling reactions.

References [1] E. M. Leitao, T. Jurca, I. Manners, Nat. Chem. 2013, 5, 817-829, and references therein;

[2] R. Waterman, Chem. Soc. Rev. 2013, 42, 5629-5641;

[3] N. T. Coles, M. F. Mahon, R. L Webster, Organometallics 2017, 36, 11, 2262-2268;

[4] A. K. King, K. J. Gallagher, M. F. Mahon, R. L. Webster, Chem. Eur. J. 2017, 23, 9039–9043; M. EspinalViguri, S.

E. Neal, N. T. Coles, S. A. Mcgregor, R. L Webster, J. Am. Chem. Soc. 2019, 141, 1, 572-582.

[5] D. J. Liptrot, M. Arrowsmith, A. L. Colebatch, T. J. Hadlington, M. S. Hill, G. Kociok-Köhn, M. F. Mahon, Angew.

Chem. Int. Ed. 2015, 54, 15280-15283.

OL13: Oral presentation 13: Jason Lynam (University of York, York, UK)

Probing manganese-catalysed C–H functionalisation with time-resolved

infra-red spectroscopy

L. Anders Hammarback,1 Benjamin J. Aucott,

1 Jonathan B. Eastwood,

1 Ian J. S. Fairlamb,

1

Jason M. Lynam,1 Alan Robinson,

2 Ian P. Clark,

3 Igor V. Sazanovich,

3 and Michael Towrie

3

1 Department of Chemistry, University of York, York, YO10 5DD, United Kingdom

2 Syngenta Crop Protection, Münchwilen, Switzerland 3 Central Laser Facility, STFC Rutherford Appleton Laboratory, Didcot, United Kingdom

e-mail: jason.lynam@york.ac.uk

There is significant interest in the use of manganese carbonyl complexes as catalysts for C-H functionalisation

reactions as replacements for less Earth-abundant platinum group metals.[1]

Simple complexes such as

[MnBr(CO)5] are able to directly couple pyridine derivatives with alkynes (Figure 1a). Although there are many

examples of such Mn-catalysed reactions,[1]

there is a lack of experimental evidence of the mechanistic steps

involved in the C-H functionalisation and C-C bond formation steps. We have employed low-temperature

photolysis, coupled with NMR spectroscopy, to identity metallacycle 2 as a key intermediate in this chemistry,

resulting from alkyne insertion in the Mn-C bond (Figure 1b).[2]

In this presentation, a comprehensive picture of the fundamental steps underpinning Mn-catalysed reactions will

be discussed. Time-resolved infrared spectroscopy (TRIR) on picosecond to microsecond timescales has been

employed to directly observe alkyne complex B and the kinetics of the subsequent insertion into the Mn-C bond

to give metallacycle C (Figure 1c) proving unique insight into the C-C bond formation step which underpins the

catalytic cycle.[3]

These studies have been

used to (1) determine the

rate of binding of the alkyne

to the metal, (2) quantify

substituent effects on the C-

C bond formation step and

(3) directly observe

fundamental steps in

catalytically relevant

solutions. The insertion of a

range of unsaturated

substrates into Mn-C bonds

of a variety of

cyclomanganated complexes

will be described and the

factors controlling the rate of

CC bond formation

quantified.

References

[1] Y. Hu, B. Zhou and C. Wang, Acc. Chem. Res., 2018, 51, 816.

[2] N. P. Yahaya, K. M. Appleby, M. Teh, C. Wagner, E. Troschke, J. T. W. Bray, S. B. Duckett, L. A.

Hammarback, J. S. Ward, J. Milani, N. E. Pridmore, A. C. Whitwood, J. M. Lynam and I. J. S. Fairlamb,

Angew. Chem. Int. Ed., 2016, 55, 12455.

[3] L. Anders Hammarback, I. P. Clark, I. V. Sazanovich, M. Towrie, A. Robinson, F. Clarke, S. Meyer, I. J.

S. Fairlamb and J. M. Lynam, Nature Catal., 2018, 1, 830.

OL14: Oral presentation 14: Justin Bradley (University of East Anglia, Norwich, UK)

Mapping iron transit through ferritins

Justin M. Bradley,1 Dimitri A. Svistunenko,

2 Jacob Pullin,

2 Natalie Wan,

1 Geoffrey R.

Moore,1 Andrew M. Hemmings,

1,3 and Nick E. Le Brun

1

1 Centre for Molecular and Structural Biochemistry, School of Chemistry, University of East Anglia, Norwich,

NR4 7TJ, UK. 2 School of Biological Sciences, University of Essex, Wivenhoe Park, Colchester CO4 3SQ.

3 School of Biological Sciences, University of East Anglia, Norwich, NR4 7TJ, UK.

e-mail: Justin.Bradley@uea.ac.uk

Ferritins are multimeric iron storage/detoxification enzymes, examples of which are found in all kingdoms of

life. Each monomer unit is composed of a 4 α-helical bundle motif and catalytic activity is underpinned by a

diiron site, the ferroxidase centre, located at the centre of H-chain monomers. Here Fe2+

sequestered from

solution is oxidised to the Fe3+

state by O2 before being translocated to the interior of the protein where it is

stored as an insoluble ferric (hydr)oxy mineral core. Therefore ferritin function requires the existence of an iron

transport mechanism for Fe2+

from bulk solution to the catalytic sites and for ferric-oxo precursors of the

mineral core from the catalytic sites to the interior cavity. 24-meric ferritin cages self-assemble into rhombic

dodecahedra. Channels formed at the 3-fold vertices of these dodecahedra have been shown to be the route of

Fe2+

entry into animal ferritins. Two ‘rings’ of carboxylate sidechains provide both a hydrophilic environment

and a favourable electrostatic gradient for Fe2+

entry.[1]

These residues are conserved among the animal proteins

and disruption of either by site directed mutagenesis leads to loss of catalytic activity. This has led to the

suggestion that both carboxylates are required for Fe2+

entry via this 3-fold channel. Following exit from the

channel on the interior surface of the protein, incoming Fe2+

is shuttled to the catalytic site via two transient

binding sites, Fe3 and Fe4.[2]

Post oxidation, iron-oxo clusters are thought to exit the ferroxidase centre along the

axis of the α-helical bundle before entering the internal cavity at the base of another channel formed at the 4-

fold vertices.

The channels penetrating prokaryotic ferritins bear little similarity to those in their counterparts from animals

and in contrast, very little is known about the route of iron transit through these proteins. SynFtn is a ferritin

isolated from a marine dwelling cyanobacterium that has recently been shown to utilise a highly unusual

mechanism of iron oxidation.[3]

Here we report the use of site directed mutagenesis in conjunction with

structural, spectroscopic and kinetic data to demonstrate that the 3-fold channel constitutes the route of Fe2+

entry into this protein. However, the channel contains only one ring of carboxylate residues in the mid-channel

position and yet is still able to facilitate efficient passage of iron through the protein cage. Furthermore, the

transient iron binding sites required for Fe2+

entry in animal ferritins are absent from SynFtn but a conserved

glutamate that acts a ligand to site Fe3 in human ferritin is required for efficient release of Fe3+

from the

ferroxidase centre of SynFtn following oxidation. Therefore, the route of iron transit from 3-fold channel to

active site, and ultimately the mineral core, is divergent between SynFtn and the animal proteins. Finally our

data suggest that the second ring of carboxylates found in the 3-fold channels of animal ferritins may play a

greater role in completing the iron transfer chain found in these proteins rather than in generating a favourable

electrostatic gradient for Fe2+

uptake as was previously thought.

References

[1] Behera RK, et al. J. Biol. Inorg. Chem. 2015, 20, 957-969.

[2] Pozzi C, et al. Acta Crystallographica Section D-Structural Biology 2015, 71, 1909-1920.

[3] Bradley JM, et al. Proc. Natl. Acad. Sci. USA 2019, https://doi.org/10.1073/pnas.1809913116.

OL15: Oral presentation 15: Galvin Leung (University of Leicester, Leicester, UK)

Precise determination of heme binding affinity in proteins

Galvin C.-H. Leung,a Simon S.-P. Fung,

a Nicholas R. B. Dovey,

a Emma L. Raven

b and

Andrew J. Hudsona

a Department of Chemistry and the Leicester Institute of Structural & Chemical Biology, University of Leicester,

Leicester, LE1 7RH, United Kingdom. b School of Chemistry, University of Bristol, Bristol, BS8 1TS, United Kingdom.

e-mail: gchl2@leicester.ac.uk

There is accumulating evidence to suggest the existence of pools of labile heme in cells, which interacts

transiently, as a signalling molecule, on target proteins. The transient nature of the interactions means that the

relevant apo-proteins must have a much lower affinity for heme compared to traditionally defined heme

proteins. We have developed a new method for accurately determining binding affinity to transient heme-

binding proteins from a spectrophotometric titration of the apo-protein with hemin. The challenge to precise

determination of the binding affinity is being able to discriminate between the Soret absorbance for the product

(holo-protein) and that for the titrant (unbound hemin). This can be done approximately by difference

absorption. We present a more reliable approach to separate contributions made by these two components to

absorbance values by employing a computational algorithm. Regions of the spectrum that exhibit the highest

degree of variance during the course of a titration were identified by a multivariate method in order to estimate

the pure component spectra and concentration profiles. This approach has significant advantages over existing

methods for spectrophotometric determination of heme binding. First, more precise determination of

dissociation constants, Kd, can be made because the titration curves for the apo-protein, holo-protein and

unbound heme are calculated and all three components can be fitted to a theoretical-binding model. Second, an

absorption spectrum for the pure holo-protein is calculated. This is a unique advantage of MCR and it is

attractive for investigating proteins in which the nature of heme binding has not, hitherto, been characterised

because the holo-protein spectrum can provide information on the heme-protein interaction.

OL16: Oral presentation 16: Charlène Esmieu (University of Toulouse, Toulouse, France)

Effect of the N-truncation of Aβ peptides on the ROS production by their

copper complexes – Friends or enemies?

Charlène Esmieu,a Guillaume Ferrand,

a Valentina Borghesani,

a Christelle Hureau

a

Laboratoire de Chimie de Coordination (LCC), 205 Route de Narbonne, 31400 Toulouse, France.

e-mail: charlene.esmieu@lcc-toulouse.fr

High- Alzheimer's disease (AD) is the most common neurodegenerative disease and the major cause of

dementia throughout the world that makes it one of the biggest challenges of the 21st century in public health.

The prevalence of this disease is expected to increase rapidly in the coming decades. Although the mechanisms

underlying this complex pathology are not yet fully understood, a broad consensus attributes the early

development of AD to a so called amyloid cascade. This deleterious process relies on the disturbed equilibrium

between the production of a peptide called amyloid-β and its degradation by other proteases. This results in a

significant increase of it concentration extracellularly, leading to its aggregation via the formation of oligomers,

protofibrils and fibrils.[1]

These assemblages come together to form amyloid plaques, a distinctive post-mortem

marker of the disease. Different forms of Aβ peptides are found in the senile plaques, such as the “full-length”

Aβ1-40/42 peptide and the N-truncated peptides Aβn-40/42 (position 1 to 5).[2-5]

Strong evidences have associated the

high toxicity of Cu-containing aggregates to their ability to promote the oxidative stress observed in AD via the

catalytic production of reactive oxygen species (ROS).[6-7]

A lot have been done regarding the studies of the

ROS production with the full length Aβ peptide,[8]

nevertheless N-truncated forms which are little considered

are of interest because it’s thought that there are present in huge quantity in the brain and senile plaques.[3,9]

Moreover it’s admitted that they possess a protective effect again ROS production thank to their ATCUN

(Amino-Terminal Copper and

Nickel binding) type coordination

site.

Indeed, the coordination site of the

N-truncated peptides is different

from the one found in Aβ1-40/42

(Figure 1) which confers them

different properties regarding the

ROS production.[10]

Here we

present the results of the study of

the ROS production obtained with

two N-terminal Aβ isoforms found

in the brain: Aβ4-n and Aβ11-n. This

study aims to clarify/investigate the following points: (i) the ROS production of CuII/I

Aβ4/11-16 in our

experimental conditions, and (ii) the effect of the presence of Aβ4/11-n on the ROS production by CuII/I

Aβ1-16.

References [1] Kozlowski, H.; Luczkowski, M.; Remelli, M.; Valensin, D. Coord. Chem. Rev. 2012, 256, 2129-2141.

[2] Bayer, T. A.; Wirths, O., Acta Neuropathologica 2014, 12è, 787-801.

[3] Lewis, H.; Beher, D.; Cookson, N.; Oakley, et al, Neuropath. Appl. Neurobiol. 2006, 32, 103-118.

[4] Portelius, E.; Tran, A. J.; Andreasson, U.; Persson, R. et al, J. Proteome Res. 2007, 6, 4433-4439.

[5] Portelius, E. B., N.; Gustavsson, M. K.; Volkmann, I.; Brinkmalm, G. et al., Acta Neuropathol. 2010, 120,

185-193.

[6] Kenche, V. B.; Barnham, K. J., British J. Pharmacol. 2011, 163, 211-219.

[7] Cheignon, C.; Tomas, M.; Bonnefont-Rousselot, D.; Faller, P. et al., Redox Biol. 2018, 14, 450-464.

[8] Hureau, C., Coord. Chem. Rev. 2012, 256, 2164-2174.

[9] Liu, K.; Solano, I.; Mann, D.; Lemere, C. et al., Acta Neuropathol. 2006, 112, 163-174.

[10] Borghesani, V.; Alies, B.; Hureau, C., Eur. J. Inorg. Chem. 2018, 7-15.

OL17: Oral presentation 17: Hazel Girvan (University of Manchester, Manchester, UK)

Mechanistic and structural studies on members of the CYP152

peroxygenase family of cytochromes P450

Hazel M Girvan, Harshwardhan Poddar, Alessia Andrews, Kirsty J Mclean, Muralidharan

Shanmugan, David Leys, Andrew W Munro

Manchester Institute of Biotechnology, The University of Manchester, 131 Princess St, Manchester M17DN,

Manchester, UK. e-mail: Hazel.girvan@manchester.ac.uk

The cytochromes P450s (CYPs) are a ubiquitous superfamily of heme b containing enzymes, catalysing the

oxidative transformation of a wide variety of substrates including fatty acids, steroids and terpenes. The

CYP152 family of CYP enzymes are a growing family of bacterial peroxygenases. Instead of receiving

electrons from NAD(P)H via redox partners, as is the case for almost all other CYPs, the CYP152 family use

hydrogen peroxide to drive oxidation (typically hydroxylation) and decarboxylation of fatty acid substrates.

They have potential roles in biofuel production, generating terminal- alkenes from fatty acids for direct use in

the current transport infrastructure and therefore being of great interest to the biotechnology industry. We have

characterised a number of members of the family, including the fatty acid decarboxylase OleT from

Jeotgalicocus sp and the fatty acid hydroxylase CYP152K6 from Bacillus methanolicus using a range of

structural, spectroscopic and biophysical techniques.

OL18: Oral presentation 18: Megan Greaves (University of Strathclyde, Glasgow, UK)

Probing the Mechanism of Oxidative Addition of Alkyl Substrates to Ni0

Megan Greaves,1 David Nelson,

1 T. Ronson,

2 S. Sproules

3

1 Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow, G1

1XL, UK. 2 AstraZeneca, Charter Way, Macclesfield, SK10 2NA, UK. 3WestCHEM School of Chemistry, University of

Glasgow, University Avenue, Glasgow, G12 8QQ, UK.

e-mail: megan.greaves@strath.ac.uk

Palladium-catalysed cross coupling reactions such as Suzuki-Miyaura, Negishi, Kumada-Corriu, and Heck[1–4]

are widely used in industry today to make otherwise difficult to access carbon-carbon bonds. A desire to move

away from palladium and towards nickel has become apparent, mostly due to the ability of nickel to react with

alternative substrates and the lower prices that are associated with this less precious metal. To fully optimise

reaction conditions involving nickel, the mechanism needs to be understood. Previously we have studied the

kinetics of oxidative addition of aryl halides to Ni(COD)(dppf); this work looks into the kinetics of the same

reaction but with alkyl substrates which appear to go via a very different mechanism.[5]

It was found that an equilibrium forms between Ni(COD)(dppf) (with small amounts of free dppf ligand) and

Ni(dppf)2 which is now thought to be the active species. Evidence of radicals has also been observed during the

oxidative addition process. An extensive additive scope has been investigated to determine which species

accelerate or inhibit the oxidative addition which is helping bring us closer to elucidating the mechanism of this

vital step within many catalytic cycles.

References

[1] A. Suzuki, N. Miyaura and K. Yamada, Tetrahedron Lett., 1979, 36, 3437–3440.

[2] E. Negishi and S. Baba, J. Chem. Soc. Chem. Commun., 1976, 596–597.

[3] K. Tamao, K. Sumitani and M. Kumada, J. Am. Chem. Soc., 1972, 94, 4374–4376.

[4] K. F. Heck and J. P. Nolley, J. Org. Chem., 1972, 37, 2320–2322.

[5] S. Bajo, G. Laidlaw, A. R. Kennedy, S. Sproules and D. J. Nelson, Organometallics, 2017, 36, 1662–1672.

OL19: Oral presentation 19: Amanda Jarvis (University of Edinburgh, Edinburgh, UK)

Artificial metalloenzymes for hydrocarbon functionalisation

Amanda Jarvis

University of Edinburgh, Edinburgh, UK. e-mail: amanda.jarvis@ed.ac.uk

One of the major challenges facing the chemical industries is the sustainable creation of chemicals from natural

resources. Reactions such as the functionalization of C=C and C-H bonds lend themselves to sustainable

processes, as they are atom economical. Increasing the selectivity of these reactions is an important goal to

ensure these processes will be utilized by the chemical industries. Inspired by enzymes, which are highly

selective catalysts, our work combines traditional homogenous catalysis and biocatalysis through the

development of artificial metalloenzymes to create catalysts for the direct functionalization of hydrocarbon

skeletons. A number of different methods can achieve the introduction of a synthetic metal center into a protein

scaffold to obtain an artificial metalloenzyme. These include the covalent modification of the protein’s natural

amino acids (e.g. cysteine) with a metal binding ligand containing a reactive linker. In this talk, I will cover our

work towards developing artificial metalloenzymes using this method for a range of synthetic challenges from

reactions in water to C-H functionalization.

OL20: Oral presentation 20: Ulrich Hintermair (University of Bath, Bath, UK).

Is there an Alternative to the Haber-Bosch process? An ab-initio Analysis

of the Catalytic Oxidation of Nitrogen

Ulrich Hintermair

Centre for Sustainable Chemical Technologies, Wessex House 1.27, University of Bath, Claverton Down

Bath, BA2 7AY, Bath, United Kingdom. e-mail: uh213@bath.ac.uk

Reductive N2 activation by the Haber-Bosch process is the largest catalytic process in the world, supplying

mankind with fertilizers and a variety of essential nitrogen-containing chemicals for almost a century. Utilizing

a large excess of synthetic H2 at 300 bar and 450˚C, it consumes about 5% of the world’s natural gas production,

3% of world’s annual energy supply, and is responsible for about 4% of global CO2 emissions. However, most

of the energy content in the NH3 product is then lost in the ensuing Ostwald process that oxidizes the ammonia

to nitrate, the main component of artificial fertilizers.

Direct oxidative N2 activation could be an alternative pathway that circumvents the need for fossil H2, however,

the activation energy for the thermal reaction of N2 with O2 is so high that it only occurs under extreme

conditions. Currently no catalysts are known that would lower the activation temperature into a manageable

regime. We have investigated the possibility of catalytic N2 oxidation by a first-principles thermodynamic

analysis, and computed plausible reaction pathways to guide future catalyst development.

OL21: Oral presentation 21: Sophie Kendall-Price (University of Oxford, Oxford, UK).

Combining solution and single crystal IR spectroelectrochemistry reveals

details of the [NiFe] hydrogenase catalytic cycle

Sophie Kendall-Price, Philip Ash, Kylie Vincent

Department of Chemistry, University of Oxford, Oxford OX1 3QR, United Kingdom.

e-mail: sophie.kendall-price@chem.ox.ac.uk

High efficiency and selectivity towards H2 oxidation, in combination with resilience towards O2 inactivation,

make nickel-iron hydrogenases ideal models for the development of synthetic catalysts for fuel cells and clean

H2 production, alongside other biotechnological applications. The [NiFe] hydrogenase catalytic cycle for H2/H+

interconversion contains 4 established active states, two of which (Nia-R and Nia-L) have been shown to be

composed of up to three sub-states (Figure 1a). Protein film infrared electrochemistry (PFIRE) experiments have

shown that multiple Nia-R and Nia-L sub-states appear under turnover conditions, suggesting they may all be

catalytically relevant.[1]

However, PFIRE measures steady-state turnover and so these experiments alone are

unable to resolve the kinetics of transitions between these sub-states due to their rapid interconversion. We have

developed a single crystal approach that combines electrochemical control with in situ synchrotron infrared

microspectroscopic sampling (Figure 1b)[2]

and this offers the possibility for obtaining time resolved details of

chemical steps which are too fast to resolve in solution studies (Figure 1c). This complements the steady-state

PFIRE investigations, providing further insight into the role of individual proton transfer sub-states in the [NiFe]

hydrogenase catalytic cycle.

Fig. 1. (a) The outline catalytic cycle of NiFe hydrogenase. The Nia-R and Nia-L species are composed of up to

3 sub-states, I, II, III. (b) Visible images of a hydrogenase crystal on the electrode showing a 10 10 µm2 IR

sampling area (white square). (c) Top: IR spectra of an electrochemical redox titration of a single crystal of E.

coli [NiFe] hydrogenase 1. Bottom: Kinetic traces collected at 1.8 s time resolution during reduction from -95 to

-395 mV showing the formation of Nia-RII and Nia-RIII and loss of Nia-SI.

References

[1] Hidalgo, R., Ash, P. A., Healy, A. J., Vincent, K. A. Angew. Chemie. Int. Ed. 2015, 54, 7110-7113.

[2] Ash, P. A., Carr, S. B., Reeve, H. A., Skorupskaitė, A., Rowbotham, J., Shutt, R., Frogley, M., Evans,

R. M., Cinque, G., Armstrong, F. A., Vincent, K. A. Chem. Commun. 2017, 53, 5858.

P1: Poster 1: Felicia Ejiah (Lagos, Nigeria)

Studies on some cobalt(II) complexes with Schiff bases derived from

aminophenols with antiseptic and antibacterial potentials

F. N. Ejiah,1 T. M. Fasina,

1 N. Revaprasadu,

2 F. T Ogunsola

3 and O. B. Familoni

1

1 Department of Chemistry, Faculty of Science, University of Lagos, Nigeria.

2 Department of Chemistry, University of Zululand, South Africa

3 Department of Medical Microbiology, College of Medicine, University of Lagos, Nigeria

e-mail: fejiah@unilag.edu.ng

The present study was carried out to investigate the effect of substituent groups on the antibacterial activities of

2-aminophenol Schiff bases and their cobalt(II) complexes. The search for new compounds with potential

effects against pathogenic organisms has become necessary due to the increase in microbial resistance reported

for existing antiseptics and disinfectants. In line with this, new cobalt(II) complexes with Schiff bases derived 2-

aminophenol and p-substituted benzaldehydes were synthesised. The compounds were fully characterized using

elemental analysis, mass spectrometry, atomic absorption spectroscopy, infrared spectroscopy, 1H NMR,

electronic absorption spectroscopy, magnetic susceptibility measurements and thermal gravimetry analysis.

Results indicate that all metal complexes had a 1:2 metal ligand ratio with magnetic moments characteristic of

octahedral and tetrahedral geometry around the metal ion. The Schiff bases and their metal complexes were

screened for in-vitro antibacterial activities against 6 human pathogenic bacteria usually found around the

hospitals and homes; Escherichia coli (ATCC 8739), Staphylococcus aureus (ATCC 6538), Pseudomonas

aeruginosa (ATCC 19582), Bacillus cereus (10702), Enterococcus faecalis (ATCC 29212) and Kribsella

pneumonia (ATCC 10031). Sodium hypochlorite and ampicillin were used as a reference compounds. The result

showed that Schiff bases exhibited moderate inhibitory activity against the tested microorganisms similar to

sodium hypochlorite. The Schiff base metal complexes exhibited higher antibacterial activity when compared to

sodium hypochlorite and ampicillin. Our results show that these complexes can be employed as active

ingredients in development of broad spectrum antiseptic agents.

P2: Poster 2: Melissa Stewart (Norwich, UK)

WhiB-like proteins and their Fe-S dependent protein-protein interactions

Melissa Y. Y. Stewart,1 Jason C. Crack,

1 Matt J. Bush,

2 Mark J. Buttner,

2 and Nick E. Le

Brun1

1 University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, UK

2 John Innes Centre, Norwich Research Park, Norwich, NR4 7UH, United Kingdom.

e-mail: melissa.stewart@uea.ac.uk

WhiB-like (Wbl) proteins are iron-sulfur (Fe-S) cluster proteins unique to Actinobacteria, a phylum of Gram-

positive bacteria that includes medically important pathogens such as Mycobacterium tuberculosis, and soil

bacteria belonging to the Streptomyces genus, the source of over half of all clinically useful antibiotics. Wbl

proteins are important for the ability of M. tuberculosis to persist in an antibiotic resistant state in the host for

prolonged periods of time, and for sporulation in Streptomyces species.

Mutagenesis studies of the four conserved cysteines which coordinate the Fe-S cluster show them to be crucial

for Wbl protein function. Furthermore, at least some Wbl proteins appear to be sensors of nitric oxide (NO), and

WhiD from Streptomyces coelicolor and WhiB1 from M. tuberculosis have been previously shown to undergo a

rapid, complex reaction with NO, reaching completion after the sequential addition of 8 NO molecules per

cluster. This appears to give rise to a mixture of protein-bound iron-nitrosyl complexes with similarities to well-

known inorganic small molecule iron-nitrosyls.

The mechanisms by which Wbl proteins function have yet to be clearly demonstrated. They appear to act as

transcriptional regulators, but in some cases at least this occurs via an interaction with another protein. For

example, in S. coelicolor, the WhiB regulon has been shown to be identical to that of the WhiA protein (a

regulator required for sporulation), indicating that the proteins cooperate to effect transcriptional control. WhiA

is not itself an Fe-S cluster protein, it is nevertheless unusual in that it has an N terminal domain related to a

class of homing endonucleases, but lacks the residues required for catalysis. The link between Wbl proteins and

a number of sigma factors has also been documented, the implications of these interactions is currently

unknown.

The aim of this work is to gain insight into the Wbl proteins from S. venezuelae, in terms of both their reaction

with NO and interactions with potential partner proteins, and the mechanisms for signal transduction. To do this,

both non-denaturing and LC-MS methodologies are being employed alongside more traditional bioanalytical

and spectroscopic approaches.

Acknowledgements:

This work was supported by the BBSRC Norwich Research Park Biosciences Doctoral Training Partnership

P3: Poster 3: Marta Chrzanowska (Toruń, Poland)

Effect of steric hindrance on the reactivity of [RuII(terpy)(N^N)Cl]

+

complexes

M. Chrzanowska,a A. Katafias,

a R. van Eldik

a,b

a Faculty of Chemistry, N. Copernicus University, Gagarina 7, 87-100 Toruń, Poland

b Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland.

e-mail: katafias@umk.pl

Our earlier work[1,2]

focused on studies of the reactivity of polypyridyl ruthenium(II) complexes of the

[RuII(terpy)(N^N)X]

+/2+ type (where X = Cl

- or H2O, terpy = 2,2’:6’,2’’-terpyridine and N^N = 1,10-

phenantroline (phen), 2,2’-bipyridine (bipy), 2-(aminomethyl)pyridine (ampy) or ethylenediamine (en)) in terms

of monodentate ligand exchange reactions. The reactivity of both the chlorido and aqua derivatives of the

studied Ru(II) complexes increased in the order [RuII(terpy)(phen)X]

+/2+ < [Ru

II(terpy)(bipy)X]

+/2+ <

[RuII(terpy)(ampy)X]

+/2+ < [Ru

II(terpy)(en)X]

+/2+. Our results showed that the reactivity and pKa values of the

Ru(II) complexes can be tuned by a systematic variation of electronic effects provided by the bidentate spectator

chelates and the steric hindrance caused by the bipy and phen ligand, as compared to the ampy and en chelates.

In order to verify the effect of steric hindrance on the reactivity of the examined complexes, we now extended

the series to the [Ru(terpy)(tmen)Cl]Cl complex, where tmen = N,N,N',N'-tetramethylethylenediamine. The

complex was identified in solution by multinuclear NMR spectroscopy in an appropriate solvent (e.g. d6-

DMSO) and ESI-MS in water. The stability of [Ru(terpy)(tmen)Cl]+ in aqueous solution, the acidity and

substitution behaviour of the corresponding aqua derivative by chloride, thiourea and N,N'-dimethylthiourea,

were studied. We found that the reactivity of the tmen complex is similar to that of the bipy complex for both

the aquation and substitution reactions studied. The results clearly show that the steric hindrance has a

significant impact on the lability of the studied Ru(II) complexes. The reactivity of the complexes increase in

the order phen < bipy ≈ tmen < ampy < en.

References

[1] M. Chrzanowska, A. Katafias, O. Impert, A. Kozakiewicz, A. Surdykowski, P. Brzozowska, A. Franke, A.

Zahl, R. Puchta, R. van Eldik. Dalton Trans., 2017, 46, 10264.

[2] M. Chrzanowska, A. Katafias, A. Kozakiewicz, R. Puchta, R. van Eldik. J. Coord. Chem., 2018, 71, 1761.

P4: Poster 4: Manel Martínez (Barcelona, Spain)

Redox-assisted assembly of a new mixed-valence Co(III)/Fe(II) cyanido-

bridged closed shell cube; formation mechanism, characterisation and

redox reactivity

M. Ferrer, M. Gonzálvez, M. Martínez

Secció de Química Inorgànica, Departament de Química Inorgànica I Orgànica, Universitat de Barcelona,

Barcelona, Spain.

e-mail: manel.martinez@qi.ub.edu

The redox-assisted assembly[1-3]

for mixed-valence Co(III)LS/Fe(II)LS complexes based on the mechanism:

has been utilised for the preparation of a novel CoIII

4/FeII

4 cubic cage by selecting an inert tridentate skeleton on

the Co(III) starting material.

The new complex has been characterised by the ICP Fe/Co ratio, ESI-MS, UV-Vis, NMR and CV. The complex

undergoes the usual oxidation process with S2O82-

, which is reversed on addition of OH-.[4,5]

References

[1] Alcázar, L.; Aullón, G.; Ferrer, M.; Martínez, M. Chem. Eur. J. 2016, 22, 15227-15230.

[2] Bernhardt, P. V.; Bozoglián, F.; González, G.; Martínez, M.; Macpherson, B. P.; Sienra, B. Inorg. Chem.

2006, 45, 74-82.

[3] Bernhardt, P. V.; Bozoglián, F.; Macpherson, B. P.; Martínez, M. Coord. Chem. Rev. 2005, 249, 1902-

1916.

[4] Alcázar, L.; Bernhardt, P. V.; Ferrer, M.; Font-Bardia, M.; Gallen, A.; Jover, J.; Martínez, M.; Peters, J.;

Zerk, T. J. Inorg. Chem. 2018, 57, 8465-8475.

[5] Bernhardt, P. V.; Bozoglián, F.; Macpherson, B. P.; Martínez, M.; Merbach, A. E.; González, G.; Sienra,

B. Inorg. Chem. 2004, 43, 7187-7195.

[6] Financial support from the Spanish MINECO CTQ2015-65707-C2-1-P (MINECO/FEDER) is

acknowledged.

P5: Poster 5: Niting Zeng (Manchester, UK)

Direct synthesis of MoS2 or MoO3 via single source precursor – with

potential for applications in biological systems

Niting Zeng and David J. Lewis

School of Materials, The University of Manchester, Oxford Road, M13 9PL, United Kingdom.

e-mail: niting.zeng@manchester.ac.uk

One of the main motivations behind current research in two-dimensional (2D) materials in lab is scalable

processing pathway. We aim to synthesis 2D materials in a scalable and high-efficient way by single source

precursor - Dialkyl Dithiocarbamato Molybdenum(IV) [Mo(DTC)4]. High-purity 2H-MoS2 or α-MoO3 has been

made by the direct synthesis from Mo(DTC)4. The product was simply controlled by processing condition:

argon or air. The characterisation shows that the 2H-MoS2 is free-standing and nanostructured whilst

polycrystalline α-MoO3 is produced in air. The low temperature (450°C) combined with the short processing

time (1 h) for both pathways indicates a new soft synthetic route toward these important functional inorganic

materials and their potential in biomedical applications.

P6: Poster 6: Yen-Ting Lin (Manchester, UK)

Computational Study on The Reaction Mechanism of the Nonheme Iron

Decarboxylase UndA: Effect of pH on Catalysis

Yen-Ting Lin

Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, The

University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom.

e-mail: yen-ting.lin@postgrad.manchester.ac.uk

Aliphatic medium-chain 1-alkenes have important physical chemical properties that makes them relevant for

biofuel applications particularly due to their low freezing point, high energy content, easy product recovery, and

are highly desirable for current engines. Interestingly, compounds, such as 1-undecene, are naturally produced

by Pseudomonas as a semi-volatile metabolite.

Recently, a nonheme iron decarboxylase (UndA) was discovered involved in the 1-undecene biosynthesis and

thereby is able to convert medium-chain fatty acids into terminal olefins. We performed a computational study

using a large active site model on the reaction mechanism of hexanoic acid activation by an iron(III)-superoxo

reactant leading to 1-pentene and CO2 products and investigated the effect of active site protonation states. More

importantly, our computational study unveils that nonheme iron oxidases, such as UndA, can selectively

transform medium-chain fatty acids into the equivalent terminal olefins using an iron(III)-superoxo reactant.

In this project, we specifically focused on the protonation state of an active site Glu159 residue and show that this

affects the thermodynamics as well as the kinetics of the reaction. In conclusion, our computational studies not

only validate and match the results of the experimental perspective and predict beta hydrogen atom abstraction,

but we also show that the UndA enzyme requires active site polarization in order to stabilize the reaction

mechanism.

P7: Poster 7: Miron Leanca (Manchester, UK)

Speciation of biomineral targets in Plasmodia using +ve ion electrospray

mass spectrometry, EPR and DFT methodsis

Miron A. Leanca,1 Alexandra E. Kelly-Hunt,

1 Mark Horgan,

1 Charles E. Hill,

1 Valentina

Lukinović,2 Philip G. Evans,

3 Jatinder P. Bassin,

9 David G. Griffiths,

4 Said Alizadeh-

Shekalgourabi,4 Roger H. Bisby,

5 Michael G. B. Drew,

6 Verity Male,

6 Alessio Del Casino,

1

James F. Dunn,1 Laura E. Randle,

1 Nicola M. Dempster,

1 Lutfun Nahar,

1 Satyajit D. Sarker,

1

Fabian G. Cantú Reinhard,7 Sam P. de Visser,

7 Mike J. Dascombe,

8 Alistair J. Fielding,

1 Fyaz

M. D. Ismail1

1 School of Pharmacy and Biomolecular Sciences, Liverpool John Moores University, Byrom Street L3 3AF

Merseyside, 2 School of Chemistry and the Photon Science Institute, University of Manchester, Manchester, M13 9PL,

3 Peakdale Molecular Limited, Discovery Park, Sandwich, Kent, CT13 9FF,

4 Department of Pharmacy, University of Hertfordshire, Hatfield, Hertfordshire, AL10 9AB,

5 Biomedical Sciences Research Institute, University of Salford, Salford, M5 4WT,

6 School of Chemistry, The University of Reading, Whiteknights, Reading, RG6 6AD,

7 Manchester Institute of Biotechnology, School of Chemical Engineering and Analytical Science, The

University of Manchester, 131 Princess Street, Manchester, M1 7DN, 8 Faculty of Biology, Medicine and Health, Stopford Building 1.124, The University of Manchester, Oxford

Road, Manchester, United Kingdom.

e-mail: miron.leanca@gmail.com

In order to design more useful antimalarials, an intimate knowledge of the shape, conformation and ligand status

of various putative antimalarial drug receptors is required. One popular and often inferred candidate is the heme

μ-oxo dimer (μ-oD). Although a variety of techniques can readily probe drug-protein receptor structures,

especially vibrational, NMR and powder diffraction techniques, the presence of paramagnetic centres within

porphyrins (found in malaria parasite receptors) complicates investigations (esp. 2D NMR techniques). In

contrast, investigations applying mass spectrometry and vibrational analysis allow deeper insight into the

species involved. There are various methods of making μ-oDs, and in this study methods commonly used in

malaria investigation are employed, highlighting successful methods for their production as salts and obtaining

their vibrational spectra in the solid state as well as their mass spectra under positive ionization. μ-oDs were

investigated. Briefly, a sample was then dissolved in methanol (ca. 12 μM) and subjected to ESI-MS and, in the

solid state, FT-IR spectroscopy. As a result, a Fe-O-Fe bridge signature peak at 900 ± 5 cm-1 has been identified

and confirmed with expected m/z values. Unexpectedly, ESI-mass spectrometric analysis of standard hemin

chloride revealed presence of both reciprocal dimer and μ-oxo Dimer.

Reference

Fielding, A., Lukinović, V., Evans, P., Alizadeh-Shekalgourabi, S., Bisby, R., & Drew, M. et al. Modulation of

Antimalarial Activity at a Putative Bisquinoline Receptor In Vivo Using Fluorinated Bisquinolines. Chem. Eur.

J. 2017, 23, 6811-6828. doi: 10.1002/chem.201605099.

P8: Poster 8: Alex Miller (Liverpool John Moores University, Liverpool, UK)

Cyclic voltammetry and electron paramagnetic resonance characterization

of laccase from Aspergillus sp: ABTS and TEMPO mediator oxidation

Alex H. Miller1,2

and Alistair J. Fielding2

1 São Paulo State University, UNESP, São José do Rio Preto, São Paulo, Brazil

2 Liverpool John Moores University, Liverpool, United Kingdom.

e-mail: A.H.Miller@ljmu.ac.uk

Laccases are copper containing enzymes that catalyze the oxidation of many phenolic compounds by water

reduction to di-oxygen. Despite their specificity to phenolic compounds, when appropriately combined with a

mediator, laccase can also act on non-phenolic molecules. 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic

acid) [ABTS] and 2,2,6,6-tetramethylpiperidine-N-oxyl [TEMPO] are vastly studied as laccase mediator

compounds, and allow these enzymes to act over several different molecules, such as alcohols, lignin polymers,

etc. Each of these mediators has its own characteristic that not only differ on chemical content but also

physicochemical properties. Understanding some of these properties may be key to correct application of these

enzymes to systems where a mediator is required. In order to assess the behavior of commercial laccase from

Aspergillus sp (LAsp) towards ABTS and TEMPO oxidation, cyclic voltammetry (CV) and electron

paramagnetic resonance (EPR) spectroscopy were used to follow the redox behaviour of the reaction. The

results provide information of the optimum environment for catalysis, such as pH and temperature, which may

lead to enzyme structural changes, most likely related to the copper catalytic site.

Acknowledgements

FAPESP (Proc. 2018/21483-3)

P9: Poster 9: Emilie Gérard (University of Manchester, Manchester, UK)

Mechanistic investigation of oxygen rebound in a mononuclear nonheme

iron complex

Emilie F. Gérard,1 Thomas M. Pangia,

2 Joshua R. Prendergast,

3 Yen-Ting Lin,

1 Guy N. L.

Jameson,3 David P. Goldberg

2 and Sam P. de Visser

1

1 Manchester Institute of Biotechnology and School of Chemical Engineering and Analytical Science, The

University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom 2 Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street,

Baltimore, Maryland, 21218, USA 3 School of Chemistry, Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, 30

Flemington Road, Parkville, Victoria 3052, Australia

e-mail: emilie.gerard@postgrad.manchester.ac.uk

C–H bond activation of aliphatic groups by iron(IV)-oxo oxidants is known to proceed through a stepwise

mechanism with an initial hydrogen atom abstraction to give an iron(III)-hydroxo intermediate followed by OH

rebound to form the alcohol products.[1]

This mechanism has been established for nonheme iron dioxygenases as

well as heme monoxygenases, such as the cytochromes P450.[2]

We have trapped and characterized two novel

nonheme iron(III) complexes with either OH or OCH3 ligand that resemble the radical intermediates seen in

enzymatic hydroxylation. Experimental work shows that the oxygen rebound reaction in a mononuclear

nonheme iron(III) complex follows a concerted and charge-neutral process. To confirm the obtained trends, a

series of density functional theory (DFT) calculations on [FeIII

(OCH3)(N3PyO2Ph

)]+ and [Fe

III(OH)(N3PyO

2Ph)]

+

with a triphenylmethyl radical (para-X-Ph3C) containing para-X substituents (X = NO2, OMe, Ph, H, tBu and

Cl) were carried out. The transition state search confirmed the reaction mechanism put forward with a concerted

C–O bond formation step for homolytic bond formation. A Hammett plot shows a linear correlation between the

activation barrier and the electron-donating ability of the para-substituent.[3]

References

[1] Meunier, B.; de Visser, S. P.; Shaik, S. Chem. Rev. 2004, 104, 3947–3980.

[2] (a) Sono, M.; Roach, M. P.; Coulter, E. D.; Dawson, J. H. Chem. Rev. 1996, 96, 2841‒2888. (b)

Bollinger Jr, J. M.; Price, J. C.; Hoffart, L. M.; Barr, E. W.; Krebs, C. Eur. J. Inorg. Chem. 2005, 4245–

4254.

[3] Pangia, T. M.; Prendergast, J. R.; Gérard, E. F.; Yen-Ting Lin, Y.-T.; Jameson, G. N. L.; de Visser, S. P.;

Goldberg, D. P.; Submitted for publication.

rCO = 2.72

rFeO = 2.00

i64 cm1

rCO = 2.64

rFeO = 1.96

i161 cm1

TSOMeTSOH

P10: Poster 10: Adam Barrett (University of Bath, Bath, UK)

Studies towards catalytic hydrofunctionalization using germanium pre-

catalysts

Adam Barrett and Ruth L. Webster

University of Bath, Claverton Down, Bath, United Kingdom. e-mail: ab3036@bath.ac.uk

Catalysis with germanium complexes is almost entirely unknown, with only a handful of examples of lactide

polymerization being reported in the literature to date.[1]

However, the fact that germanium(IV) complexes can

catalyze these redox neutral (or σ-bond metathesis type) reactions indicates that high value, pharmaceutically

relevant transformations can be carried out with this main group element. Furthermore, studies from Roesky

have shown that Si(II) and Ge(II) are capable of undergoing oxidative addition and insertion reactions,[2]

but no

chemistry beyond this fundamental bond transformation have been investigated. This project focuses on the use

of discrete Ge pre-catalysts for organic synthesis, specifically hydrofunctionalization reactions (Scheme 1).

Scheme 1: a) Attempted stoichiometric reactions with novel germanium complexes 1a/1b. b) Potential

hydrofunctionalization reactions catalysed by 1a/1b.

References

[1] a) Davidson et al. Angew. Chem. Int. Ed. 2007, 46, 2280; b) Thomas et al. Angew. Chem. Int. Ed. 2013, 52,

13584.

[2] a) Roesky et al. J. Am. Chem. Soc. 2009, 131, 4600; b) Pati et al. Angew. Chem. Int. Ed. 2009, 48, 4246.

P11: Poster 11: Oliver Manners (University of Manchester, Manchester, UK)

Design of a minimalist peptidic model of an LPMO active site

Oliver Manners, Sam P. de Visser, Igor Larossa and Anthony Green

Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, 131 Princess

Street, Manchester M1 7DN, United Kingdom

e-mail: oliver.manners@manchester.ac.uk

Lytic Polysaccharide Monooxygenases (LPMOs) are copper metalloenzymes that activate O2 or H2O2 to

oxidatively cleave recalcitrant polysaccharides. They contain an unusual "histidine brace" copper coordination

environment consisting of the amine and imidazole of an N-terminal histidine (or 1 Me-His) residue and a

second histidine imidazole. Inspired by this motif, oligopeptide ligands for Cu(II) have been investigated as

minimalist mimics of the LPMO environment. An N-terminal His has been shown to significantly enhance the

reactivity of the copper towards oxidative cleavage of an LPMO substrate mimic. Systematic evolution gave an

optimal tripeptide motif having two histidine residues followed by an aliphatic or hydroxylic C-terminal residue.

DFT calculations, combined with kinetic and spectroscopic characterization of His-His-Gly and selected

analogues suggest that the peptidic complex is reminiscent of the natural LPMO coordination environment.

P12: Poster 12: David McLaughlin (University College Dublin, Dublin, Ireland)

Aerial oxidation of transition metal Schiff base complexes via dioxygen

activation

David Mc Laughlin, Vibe Jakobsen, Conor Kelly, Helge Müller-Bunz, Grace G. Morgan

School of Chemistry, University College Dublin, Belfield, Dublin 4, Ireland

e-mail: david.mc-laughlin@ucdconnect.ie

Dioxygen activation in cobalt complexes has been well studied and uses for the phenomenon have been found in

several different fields such as biomimetics,[1]

transport and storage of oxygen[2]

and catalytic oxidation of

organic substrates.[3]

The mechanism of uptake of molecular oxygen by cobalt complexes has been extensively

studied and it has been suggested that O2 may undergo a one electron reduction to forms a superoxide radical

which quickly reacts with another cobalt site to form a peroxo dimer.[4]

In this study we have investigated the

oxidation of Co(II) to Co(III) via dioxygen activation. Our structural and spectroscopic studies suggest that in

the binding process two Co(II) ions are oxidized to CoIII

and aerial O2 is reduced to peroxide. It was possible to

isolate and characterize a metastable peroxo Co(III) dimer intermediate which is stable at room temperature in

the solid state when removed from the mother liquor, Figure 1a. We have also studied the formation of the

dimer using EPR spectroscopy which suggests the formation of a short-lived superoxide intermediate, Figure

1b.

Figure 1: (a) Crystal structure of the Co(III) peroxo dimer. (b) EPR spectrum of reaction mixture at 78K.

References

[1] Hoffman, B.; Petering, D. Proc. Natl. Acad. Sci. 1970, 67, 637-643.

[2] Abrahamson, H. B. Systems for the Storage of Molecular Oxygen-A Study; Oklahoma Univ Norman

Dept of Chemistry: 1980.

[3] Cozzi, P. G. Chem. Soc. Rev. 2004, 33, 410-421.

[4] Fiedler, A. T.; Fischer, A. A. J. Biol. Inorg. Chem. 2017, 22, 407-424.

P13: Poster 13: Mary Ortmayer (University of Manchester, Manchester, UK)

Rewiring the ‘push-pull’ catalytic machinery of heme enzymes using an

expanded genetic code

Mary Ortmayer,1 Karl Fisher,

1 Jaswir Basran,

2 Emmanuel M. Wolde-Michael,

1 Derren J.

Heyes,1 Colin Levy,

1 Sarah Lovelock,

1 J. L. Ross Anderson,

3 Emma L. Raven,

4 Sam Hay,

1

Stephen E. J. Rigby,1 Anthony P. Green

1

1 Manchester Institute of Biotechnology, School of Chemistry, 131 Princess Street, University of Manchester,

Manchester M1 7DN, United Kingdom 2 Department of Molecular and Cell Biology and Leicester Institute of Structural and Chemical Biology, Henry

Wellcome Building, University of Leicester, University Road, Leicester LE1 7RH, United Kingdom 3 School of Biochemistry, University of Bristol, University Walk, Bristol, BS8 1TD, United Kingdom

4 School of Chemistry, Cantock’s Close, Bristol BS8 1TS, United Kingdom

e-mail: mary.ortmayer@manchester.ac.uk

Deciphering the functional significance of axial heme ligands employed by Nature requires an understanding of

how their electron donating capabilities modulate the structures and reactivities of the iconic ferryl intermediates

compounds I and II. However, probing these relationships experimentally is challenging, as ligand substitutions

accessible via conventional mutagenesis do not allow fine tuning of electron donation. Here, we exploit

engineered translation components to replace the histidine ligand of cytochrome c peroxidase (CcP) by a less

electron donating Nδ-methyl histidine (Me-His) with little effect on enzyme structure. The rate of formation (k1)

and the reactivity (k2) of compound I, a Trp191 radical cation coupled with a nearby ferryl heme, are unaffected

by ligand substitution. In contrast, proton coupled electron transfer to compound II (k3) is 10-fold slower in CcP

Me-His, providing a direct link between electron donation and compound II reactivity which can be explained

by weaker electron donation from the Me-His ligand (‘the push’) affording an electron deficient ferryl-oxygen

with reduced proton affinity (‘the pull’). Significantly, the deleterious effects of the Me-His ligand can be fully

compensated by introducing a Trp51Phe mutation, designed to increase ‘the pull’ by removing a hydrogen bond

to the ferryl-oxygen. Analogous active site substitutions in ascorbate peroxidase (APX), where electron transfer

occurs directly from substrate bound at the γ-heme edge, lead to similar activity trends to those observed in CcP,

providing further evidence in support of our mechanistic interpretations. In summary, an expanded genetic code

has allowed us to rewire the local ferryl-oxo catalytic machinery of a heme enzyme, showcasing a powerful and

versatile strategy to deconstruct highly evolved biological mechanisms.

P14: Poster 14: Mads Sondrup Møller (University of Southern Denmark, Odense, Denmark)

Gas-Solid Reactions:

In-Crystal NOx/NOx- Transformations and Arylamine Oxidation

Mads Sondrup Møller, Alexander Haag, Vickie McKee, and Christine J. McKenzie

Department of Physics, Chemistry and Pharmacy, University of Southern Denmark,

Campusvej 55, 5230 Odense M, Denmark. E-mail: madmo14@student.sdu.dk

Nitric oxide (NO) is a biological signaling molecule and a toxic and potent greenhouse gas produced as the by-

product of hydrocarbon combustion. Its reactivity with transition metal complexes in the solution state is well

developed, and its non-innocence as a ligand is a classic in coordination chemistry. Its reactivity with solid-state

metal-organic materials is however far less explored. Sorptive molecular materials may offer unexploited

potential for NO sensing and removal technologies, or for catalyzing useful transformations - in gas-solid

reactions.

We can show that NO is chemisorbed by the crystalline solid-state of complexes containing tunable[1,2]

dicobalt(II) or dicobalt(III) sites[3,4]

with an impressive cascade of in-crystal reactions. These comprise the in-

crystal syntheses of a coordinated bridging N:

O-nitrite and a nitrate counteranion, and the stepwise

oxidation of an aryl amine group on the ligand scaffold. It has been possible for a couple of phases to observe

the gas-solid reactions in a single-crystal to single-crystal transformations.

References

[1] F. B. Johansson, A. D. Bond, C. J. McKenzie, Inorg. Chem. 2007, 46, 2224–2236.

[2] M. S. Vad, F. B. Johansson, R. K. Seidler-Egdal, J. E. McGrady, S. M. Novikov, S. I. Bozhevolnyi, A.

D. Bond, C. J. McKenzie, Dalton Trans. 2013, 42, 9921–9929.

[3] J. Sundberg, L. J. Cameron, P. D. Southon, C. J. Kepert, C. J. McKenzie, Chem. Sci. 2014, 5, 4017–

4025.

[4] P. D. Southon, D. J. Price, P. K. Nielsen, C. J. McKenzie, C. J. Kepert, J. Am. Chem. Soc. 2011, 133,

10885–10891.

P15: Poster 15: Line Sofie Hansen (University of Southern Denmark, Odense, Denmark)

Iodosylbenzene activation: Metal-dependent mechanisms

Line Sofie Hansen, David P. de Sousa, and Christine J. McKenzie

Department of Physics, Chemistry and Pharmacy, University of Southern Denmark,

Campusvej 55, 5230 Odense M, Denmark. E-mail: liha414@student.sdu.dk

M(III) complexes of N,N,Nʹ-tris(2-pyridylmethyl)-ethylenediamine-Nʹ-acetate (tpena) mobilize the practical, but

highly insoluble polymeric oxidant, “hypervalent” iodosylbenzene [PhIO]n,[1,2]

by effectively extracting and

activating the monomer. This enables highly efficient selective catalytic sulfoxidations and epoxidations with a

wide substrate range. Two pathways for the Oxygen Atom Transfer from PhIO to the substrate are envisaged: A

and B. In A the direct oxidant is proposed to be a M(III)-OIPh adduct. In B, a second intermediate, a M(V)oxo

complex, is produced by heterolytic MO-IPh cleavage. To probe the mechanism, we have investigated the

reactions of analogous trivalent Cr, Fe and Ga complexes of tpena with [PhIO]n. In the absence of substrates we

have synthesized a unique Fe(III)-OIPh complex[3]

and a Cr(V)=O complex. This suggests that Pathway A and

B are pertinent for the Fe and Cr systems respectively for the catalysis reactions that are observed in the

presence of substrates for all three of these metal ions. Trends in the yields seem to reflect this proposal.

References

[1] C. Willgerodt, Ber., 1892, 25, 3494-3502.

[2] C. Wegeberg, C. G. Frankær and C. J. McKenzie, Dalton Trans, 2016, 45, 17714-17722.

[3] D. P. de Sousa, C. Wegeberg, M. V. Sørensen, S. Mørup, C. Frandsen, W. A. Donald and C. J.

McKenzie, Chem, Eur. J. 2016, 22, 3521–3890; A. Lennartson and C. J. McKenzie, Angew. Chem., Int. Ed.,

2012, 51, 6767-6770.

P16: Poster 16: Tobias Hedison (University of Manchester, Manchester, United Kingdom)

Solvent-slaved protein motions accompany proton coupled electron

transfer reactions catalysed by copper nitrite reductase

Tobias M. Hedison,1 Derren J. Heyes,

1 Muralidharan Shanmugam,

1 Andreea I. Iorgu

1 and

Nigel S. Scrutton1

1 Manchester Institute of Biotechnology and School of Chemistry, The University of Manchester, 131 Princess

Street, Manchester M1 7DN, United Kingdom. E-mail: tobias.hedison@manchester.ac.uk

Through the use of time-resolved pH-jump spectroscopy, we demonstrate how proton transfer is coupled to

inter-copper electron transfer in a copper nitrite reductase (CuNiR). Combined use of electron paramagnetic

resonance spectroscopy with solvent viscosity- and pressure-dependence pH-jump stopped-flow spectrocopy is

used to show that solvent-slaved protein motions are linked to this proton coupled electron transfer step in

CuNiR.

References

[1] T. M. Hedison, D. J. Heyes, M. Shanmugam, A. I. Iorgu and N. S. Scrutton, Chem. Commun. 2019,

accepted for publication.

P17: Poster 17: Arron Burnage (Heriot-Watt University, Edinburgh, UK)

Computational analysis of a solid state isobutane σ-complex and its

isobutene precursor

Arron L. Burnage,1 Stuart A. Macgregor,

1 Bengt E. Tegner,

1 Andrew S. Weller,

2 Antonio J.

Martínez-Martínez2 and Alexander J. Bukvic

2

1 Institute of Chemical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, United Kingdom 2 Chemistry Research Laboratories, University of Oxford, Oxford, OX1 3TA, United Kingdom.

E-mail: alb10@hw.ac.uk

The synthesis and characterisation of σ-alkane complexes in the solid state using solid-gas reactivity and single

crystal-to-single crystal (SC-SC) transformations is now well-established. Recent examples show hydrogenation

of a range of dienes including norbornadiene[1,2]

and pentadiene[3]

to give the corresponding rhodium σ-

norbornane and -pentane complexes. The stability of these species is attributed to the microenvironment

created by [BArF

4]- anions around the rhodium cation. This presentation will focus on the novel -isobutane

variant, [Rh(Cy2P(CH2)2PCy2)(C4H10)][BArF

4] derived from the SC-SC hydrogenation of the isobutene

precursor, [Rh(Cy2P(CH2)2PCy2)(C4H8)][BArF

4]. In the absence of H2 this σ-complex slowly dehydrogenates

back to the isobutene species at room temperature, providing an example of reversible acceptorless

hydrogenation/dehydrogenation of a light hydrocarbon. Exposing the isobutene complex to D2 forms the D2-

isobutane σ-complex which after prolonged exposure forms C4D10. This shows not only significant fluxional

behaviour of the isobutane ligand, but further proof that alkane σ-complexes are intermediates in C–H activation

processes.

This poster will present a computational structural analysis of the isobutene and isobutane complexes using

QTAIM (quantum theory of atoms in molecules), NCI (non-covalent interactions) and NBO (natural bonding

orbitals) methods along with solid state thermodynamic data for the experimental observations.

References

[1] S. D. Pike, A. L. Thompson, A. G. Algarra, D. C. Apperley, S. A. Macgregor and A. S. Weller,

Science, 2012, 337, 1648-1651.

[2] S. D. Pike, F. M. Chadwick, N. H. Rees, M. P. Scott, A. S. Weller, T. Krämer and S. A. Macgregor, J.

Am. Chem. Soc., 2015, 137, 820-833.

[3] F. M. Chadwick, N. H. Rees, A. S. Weller, T. Krämer, M. Iannuzzi and S. A. Macgregor, Angew.

Chem., 2016, 128, 3741-3745.

P18: Poster 18: Amirah Kamaruddin (University of Manchester, Manchester, United Kingdom)

Quantification of Halide Inhibition of O2 Reduction in Multicopper

Oxidases using Protein Film Electrochemistry

Amirah Farhan Kamaruddin,1

1 Manchester Institute of Biotechnology and School of Materials, The University of Manchester, 131 Princess

Street, Manchester M1 7DN, United Kingdom. E-mail: amirah.kamaruddin@postgrad.manchester.ac.uk

Multicopper oxidases (MCOs) efficiently couple the strong oxidative power of O2 to remove electrons from

organic molecules and metal ions. Quantifying and understanding the halide inhibition of MCOs is important for

determining their suitability for bioenergy and bioremediation applications, because halides strongly inhibit how

well these enzymes work and they are ubiquitous in the environment. There is a high degree of structural

similarity between MCOs, but their halide tolerance varies enormously. The methods for quantifying chloride

inhibition produce widely variable results. To address these needs, a new method employing analytical protein

film electrochemistry was used to produce reliable, quantitative inhibition data. The data from the

electrochemical assays were fitted with three different models based on Michaelis-Menten kinetics: competitive,

uncompetitive, and non-competitive. The best fit was determined by means of a lowest correlation coefficient

(R2). Bilirubin oxidase from the fungus Myrothecium verrucaria (MvBOD) and endospore coat protein A from

the bacterium Bacillus subtilis (BsCotA) were used for the reduction of dioxygen in the presence of chloride

anions. The degree of inhibition not only depended on organism source but also on the potential and pH studied.

Chloride inhibition of dioxygen reduction in MvBOD was found to be uncompetitive and competitive in

BsCotA.

P19: Poster 19: Sidra Ghafoor (Government College University, Faisalabad, Pakistan)

A computational perspectives of electronic excitation and vibrational

analysis of Thioxanthone acetic acid derivative

Sidra Ghafoor, Asim Mansha, Hafiz Saqib,1

1 Department of Chemistry, Government College University, Faisalabad, 38000, Pakistan.

E-mail: sidraghafoor91@gmail.com

The optimized molecular geometry, vibrational frequencies of TXAD has been investigated experimentally and

theoretically by Gaussian 09 software package. The vibrational assignments are done by the VEDA program.

Optimized molecular structures have been obtained by the Hartree-Fock (HF) and DFT methods in the gas

phase and in different solvents. The excitation energy and oscillator strength obtained from electronic spectra

were calculated by time-dependent-DFT. The charge transfer within the molecule was determined by HOMO

and LUMO analysis. Natural Bond Orbital (NBO) analysis was carried out by using NBO 5.0 program to

determine the hyperconjugative interaction and charge delocalization. Moreover, the electrostatic potential

which is the visual representation of relative polarity of molecule and thermodynamic parameters like enthalpy,

entropy, Gibbs free energy and heat capacity of thioxanthone acid derivatives were calculated at different

temperatures.

P20: Poster 20: Sangita Das (Durham University, Durham, UK)

Exclusive “Rapid and Reliable” detection of organophosphorus nerve agent

(DCP) threat in both solution and gaseous state

Sangita Das, Krishnendu Aich and James W. Walton,1

1 Durham University, United Kingdom.

E-mail: sangita.das@durham.ac.uk

In this study, a triphenylamine–benzimidazole (TPIM)-functionalised switch was synthesised for ratiometric

recognition of organophosphorus (OP) chemical vapour. Interestingly, upon addition of the nerve agent mimic

diethyl chlorophosphate (DCP), a prominent color change from colorless to yellow along with a fluorescence

color change from cyan to deep yellow was noticed. The chemodosimeter (TPIM) undergoes tandem

nucleophilic substitution reaction with DCP and shows a specific colorimetric and fluorescence alteration. The

probe selectively detects DCP over other toxic substituents studied. In addition, the detection limit of TPIM for

DCP found to be in the order of 10-8

M in solution phase using fluorescence method. We have also developed a

transportable kit for DCP using our probe (TPIM), which can detect DCP vapour with high sensitivity.

References

[1] K. Aich, S. Das, S. Gharami, L. Patra and T. K. Mondal , New J. Chem. 2017, 41, 12562.

[2] C. J. Cumming, C. Aker, M. Fisher, M. Fox, M. J. La, IEEE Trans. Geosci. Remote Sens. 2001, 39,

1119.

P21: Poster 21: David Collison (University of Manchester, Manchester, UK)

EPR National Facility at the University of Manchester

Floriana Tuna, Adam Brookfield, David Collison and Eric J. L. McInne,1

1 School of Chemistry and Photon Science Institute, The University of Manchester, Oxford Road, Manchester

M13 9PL.

E-mail: epr@manchester.ac.uk

The University of Manchester hosts the EPSRC National EPR Research Facility and Service, that

accommodates several Bruker EPR instruments, allowing CW and pulsed EPR measurements at frequencies

between 1 (L-band) and 95 GHz (W-band), along with a SQUID magnetometer. Together these make a unique

research base for studying various types of paramagnetic species and materials. EPR is of wide application in

chemistry, physics, materials, biology and medicine.

The Facility has state-of-the-art experimental techniques for multi-frequency EPR and data modelling,

including:

• Continuous wave (CW) EPR at 1, 4, 9, 24 and 34 GHz frequencies (L-, S-, X-, K- and Q- band), with

optical and electrochemical “pump-probe” methods.

• Pulsed EPR at 4, 9 and 34 GHz, for ESEEM, ENDOR, ELDOR and HYSCORE methods and

integrated AWGs at all pulsed frequencies.

• Collaborative arrangements at Oxford University for CW and pulsed EPR at 94 GHz.

• A range of spectrum simulation and data modeling software. We also hold regular training events.

Since 2017, new rules for charging at point-of-use have been phased in. If you are preparing a research proposal

for a project that may require access to our facilities, please contact us for advice.

Please contact us if you wish to discuss potential experiments, or go to:

www.chemistry.manchester.ac.uk/our-research/facilities/epr/

PSI & School of Chemistry

EPSRC National UK EPR Facility and Service

P22: Poster 22: Sultan Al-Kaabi (University of Manchester, Manchester, UK)

Halogen bond interactions in piperazine complexes

Sultan Al-Kaabi,1

1 The University of Manchester, Oxford Road, Manchester, UK.

E-mail: sultan.alkaabi@manchester.ac.uk

Halogen bonding is an attractive intermolecular interaction "occurs when there is evidence of a net attractive

interaction between an electrophilic region associated with a halogen atom in a molecular entity and a

nucleophilic region in another, or the same, molecular entity".[1]

Halogen bonds known to be an interested area

of study in crystal engineering[2]

and biology.[3]

Searching crystallographic database for interaction involving

N….I, N….Br revealed that there are 324 iodofluorobenzene structures involving N…I, whereas only 56

structures in CSD involving N…Br in bromofluorobenzene.[4]

Based on a study of the known halogen bonded systems, interactions between iodo, bromo-substituted

fluoroaromatic compounds as halogen bond donors with 1,4-diazabicyclo[2.2.2]octane (DABCO) and

Piperazine as halogen bond acceptors were investigated. Systems were studied using single-crystal diffraction

and supported by infrared spectroscopy (IR) and NMR methods.

References

[1] G. Desiraju, P. Ho, L. Kloo, A. Legon, R. Marquardt, P. Metrangolo, K. Rissanen, Pure Appl. Chem.

2013, 85, 1711-1713.

[2] P. Politzer, J. Murray, ChemPhysChem. 2013, 14, 278–294.

[3] K. Riley, J. Murray, P. Politzer, M. Concha, P. Hobza, J. Chem. Theory Comput. 2008, 5, 155-163.

[4] C. R. Groom, I. J. Bruno, M. P. Lightfoot, S. C. Ward, Acta Cryst. B 2016, 72, 171–179.