Chiral Diene Ligands for Asymmetric Catalysis
Transcript of Chiral Diene Ligands for Asymmetric Catalysis
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PLEN-1
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: , : 16:30, :
Chiral Diene Ligands for Asymmetric Catalysis
Tamio Hayashi
Institute of Materials Research and Engineering, A*STAR, Department of Chemistry, National University
of Singapore
As conceptually new chiral ligands, we reported the synthesis of enantiomerically pure chiral dienes,
whose basic diene skeleton is bicyclo[2.2.1]hepta-2,5-diene (nbd*) or bicyclo[2.2.2]octa-2,5-diene (bod*).
They have two alkyl or aryl substituents on the double bonds, one on each of the two double bonds. The
chiral diene ligands were found to be better than the conventional chiral ligands represented by chiral
bisphosphines in terms of both catalytic activity and enantioselectivity in some of the catalytic
asymmetric reactions. Their high performance was observed in rhodium-catalyzed asymmetric addition of
organoboron reagents to ,-unsaturated ketones, N-sulfonylimines, and many other related reactions [1].
In this symposium, I will present some of recent advances on the asymmetric carbon-carbon bond
forming reactions catalyzed by chiral diene/rhodium complexes [2].
[1] A review: Shintani, R.; Hayashi, T. Aldrichimica Acta 2009, 42, 31.
[2] (a) T. Nishimura, A. Noishiki, G. C. Tsui, T. Hayashi, J. Am. Chem. Soc. 2012, 134, 5056. (b) T.
Nishimura, Y. Takiguchi, T. Hayashi, J. Am. Chem. Soc. 2012, 134, 9086. (c) T. Nishimura, A. Noishiki,
T. Hayashi, Angew. Chem. Int. Ed. 2013, 52, 1777. (d) Lim, K. M.-H.; Hayashi, T. J. Am. Chem. Soc.
2015, 137, in press, and references cited therein.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: AWARD-1
:
: , : 09:00, :
AFM in water: Biomarker quantification and single molecule analysis
1 1,*
(POSTECH) 1(POSTECH)
(Atomic Force Microscope)
.
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13754, 2014) chaperone AKR2A ribosome RPL23A receptor OEP7 peptide
,
DNA, mRNA, microRNA, biomarker copy
modification .
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: POLY1-1
: Current Trends in Carbon and Carbon-composite Polymers
: , : 09:00, :
Semiconducting Polymers and Small Molecules for Transistors and
Solar Cells
Iain McCulloch
Centre for Plastic Electronics and Department of Chemistry, Imperial College, London, UK
The power conversion efficiency (PCE) of single junction organic solar cells has increased significantly
during the last decade to 9-10%, now approaching the threshold considered necessary to commercialize
the technology. During this period, the structural diversity of semiconducting donor polymers for solar
cells has increased dramatically, enabling accelerated development of bulk heterojunction (BHJ) organic
solar cells based on polymer donor materials and molecular fullerene derivatives. One aspect of this
presentation is to illustrate one molecular design strategy used to optimise a new class of donor polymer.
However, the development of electron accepting materials that lead to BHJs with high PCE has been
significantly slower. The most commonly used n-type acceptors to date remain [6,6]-phenyl-C61-butyric
acid methyl ester (PC61BM) and its slightly larger counterpart PC71BM. These fullerene acceptors have
significant limitations including weak absorption and poor tunability of absorption over the range of
intense regions of the solar spectrum; morphological instability in thin film blends over time; high
synthetic costs and limited scope for synthetic control over electronic and structural properties. For these
reasons, we have developed new, synthetically simple electron acceptor materials, based on rhodanine
end groups, which have high lying LUMO energy levels and much larger absorption coefficients that
fullerenes. In BHJ devices with P3HT donor polymer, the rhodanine molecules were demonstrated to
outperform the fullerenes. Our synthetic strategy was to make dumbbell shaped dimeric fullerenes
where the fullerenes are linked via an alkyl bridge between the ester functional group on PCBM. This was
shown to inhibit large scale crystallisation.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: POLY1-2
: Current Trends in Carbon and Carbon-composite Polymers
: , : 09:30, :
Versatile and scalable approaches to chemical processing of
nanocarbons
Milo Shaffer
Department of Chemistry, Imperial College, London, UK
Chemical functionalisation is critical to a wide range of nanotube applications, but needs to be versatile
and applicable at scale. Existing approaches tend to rely on liquid phase reactions, often requiring
damaging sonication or lengthy work up through filtration or centrifugation. The formation of
individualized functionalised single wall nanotubes (SWNTs) is a particular challenge. One approach is to
shift the modification reaction into the gas phase. We have developed a generic, scalable furnace
treatment, based on the thermochemical activation of the CNTs, followed by reaction with functional
organic monomers1. This approach allows the introduction of a wide variety of functional groups onto the
CNT surface whilst maintaining the excellent properties of the untreated materials. The underlying
mechanism of the reaction has been established and the distribution of the functionalised sites studied
using tagging experiments. The reaction is extremely versatile and can be carried out with a variety of
monomers. The reaction and the subsequent product purification can be carried out entirely in the gas-
phase, greatly simplifying work-up and improving scalability; the approach is fundamentally compatible
with the scale and equipment of many industrial nanotube synthesis processes, and is applicable to multi-
walled nanotubes, SWNTs, and other carbon-based materials6. The surface properties of these products
have been studied by direct wetting experiments on the nanoscale, dispersion studies, and inverse gas
chromatography (IGC)2. Water dispersible materials with cationic, anionic, and non-ionic surface
functionalities provide simple processing routes to a range of applications, and are particularly well suited
to studying biological interactions5,6.A different approach to nanotube processing, relies on reductive
charging. Using a liquid ammonia process3, pure nanotubides can be redissolved, purified, or optionally
functionalised without sonication. A key step is to control the ratio of charge to carbons, as it determines
both the yield and the nature of the dissolved material. The G/D ratios observed during the dissolution
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sequence, as a function of metal:carbon ratio, demonstrate a new purification method for removing
carbonaceous impurities from pristine SWNTs. The production of individualised SWNT solutions has
been confirmed by neutron scattering. A similar approach can be applied to graphene nanoplatelets4. The
resulting nanocarbon ions can be readily chemically grafted for a variety of applications, depending on
the reagent, charge density, and ionic concentration in the reaction medium9. The nature of the reactivity
of charged graphenides is unusual, due to the continuum density of states of these otherwise molecularly
discrete species10. Interestingly, the chemical charging agent can be avoided by a pure electrochemical
process that yields both nanotube anions5 and cations8, suitable for purification, functionalization, or
electrodeposition, as desired.
1. R. Menzel et al, Chem. Sci., 2010, 1, 603-8.
2. R. Menzel et al, Langmuir, 2009, 25(14), 8340; R. Menzel et al, Carbon, 2012, 134(20) 8302
3. S Fogden al, ACS Nano, 2012, 6, 54-62
4. E Milner et al, J Am Chem Soc, 2012,8302
5. S Chen et al, Biomaterials, 2014, 35, 4729
6. Hu et al, Faraday Disc., 2014, 173, 273
7. Hodge et al, ACS Nano, 2013, 1769-1778
8. Hodge et al, Nature Comm, 2013, 1989
9. Morishita et al, J Mat Chem, 2014, 2, 15022
10. Hodge et al, Faraday Disc., 2014, 172, 311
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: POLY1-3
: Current Trends in Carbon and Carbon-composite Polymers
: , : 10:00, :
Mechanical and Electrical Properties of Carbon Nanotube Fibers
* 1
(KIST) 1 /
(CNT)
. (PAN)
.
CNT CNT
. CNT
.
.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: POLY1-4
: Current Trends in Carbon and Carbon-composite Polymers
: , : 10:25, :
Hybrid Nanomaterials Based on Defective Nanocarbons: Promising
Energy and Biomedical Applications
(UNIST)
Carbon nanomaterials including fullerenes, carbon nanotubes, and graphenes represent the most important
class of materials today; their unique physical and chemical attributes advance their roles across most
advanced scientific and technology platforms. Defective nanocarbons such as graphene oxide and carbon
nanoparticles can offer various opportunities due to their facile synthetic nature, rich surface functional
groups as well as interesting photophysical properties. In particular, as a benign alternative to
semiconducting quantum dots, carbogenic nanoparticles (also known as carbon dots, CDs) have recently
received considerable attention by virtue of their interesting physical, optical, and chemical properties,
such as their photoluminescence, photostability, and electron transfer behavior. In the first part of the
presentation, the hybrid of carbon-dot-supported silver nanoparticles are exploited to exhibit the versatile
surface plasmon resonance of in polymer optoelectronic devices such as PLED and PSC with a record-
high efficiency. Moreover, a novel design is described of highly biocompatible, fluorescent, folic acid-
functionalized CDs as carriers for the photosensitizer to achieve simultaneous biological imaging and
targeted photodynamic therapy. In addition, our early effort in taking advantages of highly biocompatible
and photoluminescent CDs in other theranostic applications will be presented.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: POLY1-5
: Current Trends in Carbon and Carbon-composite Polymers
: , : 10:55, :
Preparation of carbon materials using high energy radiation
Carbon materials are widely used for a variety of applications such as energy, environment, electronics,
and bioelectronics. They have been prepared by various chemical and physical methods. Among them,
high energy radiation-based method is an attractive way to prepare and modify carbon materials due to
several advantages, such as an eco-friendly process without any harsh chemical agents, a temperature-
independent process, fast and easy controllability, and a low processing cost. In this talk, the preparation
and modification of carbon materials by high energy radiation, such as electron beams, ion beams, and -
rays, will be presented.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: POLY1-6
: Current Trends in Carbon and Carbon-composite Polymers
: , : 11:15, :
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: POLY1-7
: Current Trends in Carbon and Carbon-composite Polymers
: , : 11:40, :
Diverse Carbon-based Nanohybrid Materials for Energy Devices,
Photocatalysis, and Sensing
Nanostructured carbons have already been recognized as critical element in recent nanotechnological
applications with the development of graphene, along with conventional carbon nanotubes or graphites.
Coupling carbon moieties with semiconductors play a central role in enhancing the performance of
energy conversion and stroge devices, photocatalysis for solar fuel generation and environmental
remediation, and electrocatalytic activities. Integrating carbons with noble metal nanostructures have also
shown premise for advanced catalytic and sensing properties. A massive amount of efforts have been
devoted to the understanding of the interface properties and developing tailored hybrid nanoarchitectures.
In this presentation, fabrication of diverse types of hybrid carbon nanostructures utilizing self-assembly,
direct carbonization, hybridization of graphene, etc. will be introduced first and their detailed structural
assessment is discussed. Application of the resultant nanostructures in electrodes of energy conversion
and storage devices, visible light active photocatalysts for solar fuel and degradation of organic pollutants,
and surface-plasmon-based enhanced optical biosensing will be the main subject of discussion.Block-
copolymer-templated diverse hybrid graphitic carbons have shown promising properties as electrodes in
solar cell, fuel cell and metal-air battery. Similar types of carbon nanostructures exhibited viable activity
in visible light photocatalysis for water splitting and degradation of toxic chemicals. Finally, charged-,
doped-, or neat-graphene oxides and their reduced analogues were assembled in surface plasmon sensing
devices and enhanced sensing was demonstrated based on well-defined multilayer thin film geometries.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: POLY1-8
: Current Trends in Carbon and Carbon-composite Polymers
: , : 12:05, :
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: POLY2-1
: Current Trends in Responsive Polymers
: , : 13:30, :
Enhanced Plasmonic Sensing and Catalysis of Hybrid Metal
Nanostructures Mediated by Responsive Polymers
Stimuli-responsive polymers have been exploited in diverse nanotechnological applications. We introduce
our recent efforts to utilize pH- or temperature-sensitive polymers to enhance the function of
photocatalysis, electrocatalysis, and optical sensing. Smart bimetallic core@shell nanoparticles were
fabricated based on gold nanoparticles (AuNPs) decorated with pH-sensitive polymer shell. The
bimetallic nanostructures of AuNP@P4VP nanocomposites containing another type of metal NP at the
P4VP periphery exhibit a controlled sensing property in terms of the change in the refractive index of
surrounding media and a typical electrocatalytic activity for methanol oxidation reaction. A plasmonic
coupling sensing device was also designed, comprising gold nanoparticles (AuNPs) separated from Au
substrate through a stimuli-sensitive polymer linker layer. Plasmonic nanostructures coupled with thermo-
responsive poly(N-isopropylacrylamide) (PNIPAM) polymers were used to investigate the unique
plasmonic-coupling-based SPR sensing properties associated with swelling-shrinking transitions in the
polymer linker brush. Noble metal nanostructure coupled with responsive polymer were used to probe
unique plasmonic mediated photocatalytic properties associated with swelling-shrinking transitions in
polymer chains triggered by specific external stimuli.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: POLY2-2
: Current Trends in Responsive Polymers
: , : 14:00, :
Volume phase transition of light responsive hydrogels and their
application
Hydrogels are three-dimensional network structures of hydrophilic polymers by physical and chemical
cross-linking and can be expanded their volumes by absorption water. Some of them change its
equilibrium swelling state in responds to external stimuli, such as pH, light, temperature, and electric field.
We have found that composite hydrogels consisting of photo-thermal conversion materials embedded
within a thermally responsive polymer matrix provide an efficient means to trigger changes in volumetric
swelling by visible light irradiation. We maximized degree of volume change triggered by light by
adjusting the lower critical solution temperature (LCST) of the hydrogels, providing highly responsive
hydrogels that show rapid and significant light-induced volume change. Base on light-responsibility of
hydrogels, we have successfully fabricated light-controlled actuators, microfluidic valve, and smart
window for energy saving. For more potential applications, light-responsive hydrogels were prepared
with controlled size and shape by using microfluidic device and alginate templating method.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: POLY2-3
: Current Trends in Responsive Polymers
: , : 14:50, :
Noncovalent Polymer-Gatekeeper in Mesoporous Silica Nanoparticles
as a Targeted Drug Delivery Platform
(UNIST)
Nanoscopic delivery vehicles capable of encapsulating drug molecules and releasing them in response to
external stimuli are of great interest due to implications in therapeutic applications. Micellar assemblies
are promising scaffolds to overcome many of the problems faced with traditional chemotherapies because
of their capacity for non-covalent, hydrophobic guest molecule binding. However, the stability of
encapsulation with such self-assembled systems is limited during blood circulation because of a requisite
concentration for assembly formation and low encapsulation stability. Thus, deliberate molecular design
for stable encapsulation, targeting and triggered release is required. For this purpose, we have developed a
facile synthetic method for highly stable, polymer-caged hollow nanoparticles using a simple intra/inter-
chain crosslinking reaction. We show a simple method for the preparation of biocompatible nanovehicles
that provides the ability to encapsulate hydrophobic or hydrophilic drug molecules. We can control the
size of the nano-carriers and release kinetics depending on crosslinking in responsive to stimuli. Nano-
carriers showed great stability to encapsulate drug molecules and drugs were only released inside cell. In
addition, we can use surface modified nano-carriers for target delivery system. Hence, the stimuli
responsive nano-carrier formation using self-crosslinking polymers and the corresponding method of
surface modification are a promising platform for creating polymer nanogels for a range of biomedical
applications, from drug delivery to biosensing.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: POLY2-4
: Current Trends in Responsive Polymers
: , : 15:20, :
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: POLY2-5
: Current Trends in Responsive Polymers
: , : 15:50, :
Cross-linkable and Degradable Layer-by-Layer Assembly under
Cytocompatible Conditions for Cell-Encapsulation
* 1 2
1(KAIST) 2(UNIST)
Layer-by-layer (LbL) assembly has recently emerged as a highly versatile and promising method for
biochemical and biomedical applications. Accordingly, it is urgently necessary to develop a
cytocompatible LbL assembly technique that is stable and offers on-demand degradation and
functionalization. In this study, we developed a simple and biocompatible LbL technique that cross-links
the layers through covalent bonds under physiological conditions without requirement of any post-
treatments or additives. By utilizing the dynamic nature of the disulfide bond, stable LbL films can be
spontaneously formed during the process, further functionalized using thiol-maleimide chemistry, and
degraded in response to glutathione. In addition, we demonstrated that the method is applicable to plate
surfaces, spherical nanoparticles, and even living cells.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: INOR1-1
: New Visions in Organometallics and Nanochemistry
: , : 09:00, :
Palladium(II) Coordination Cages
Diverse poly-pyridyl N-donor ligands that can coordinate two or more remote metal centers were used to
construct desirable molecular structures. Unique cage complexes [(Me4en)3Pd3(L1)2](X)6 (L1 = 1,3,5-
tris(isonicotinoyloxyethyl)cyanurate; X-= BF4- and ClO4
-) were constructed. A single water molecule in a
skeletal cage was reversibly associated and dissociated via a combination of the adequate space, polar
environment, and conformational flexibility of the cage. In Suzuki-Miyaura C-C cross-coupling reactions,
the cage complex showed significant catalytic activity along with the effects of the isolated single water
molecule. On the other hand, we reported the synthesis and operation of a nano-dimension 24 24 15
3 ball-joint-type host-guest system consisting of unprecedented conglomerate of two distinct helical
metallacyclophanes, chiral isomer (P)-[Pd3X6(L2)2]@(M)-[Pd3X6(L2)(L3)] and its enantiomer (M)-
[Pd3X6(L2)2]@(P)-[Pd3X6(L2)(L3)], via the reaction of racemic helical metallacyclophanes, (P,M)-
[Pd3X6(L2)2] with tridentate L3, or direct reaction of 10 small components (six palladium(II), three L2, and
one L3, L2 = N,N,N-tris(2-pyridinylethyl)-1,3,5-benzenetricarboxamide; L3 = N,N,N-tris(3-
pyridinylpropyl)-1,3,5-benzenetricarboxylate; X- = Cl- and Br-). The host-guest aggregation can be
ascribed to one interaction and three -NHO=C- hydrogen-bonds along with the combined helicity.
The host-guest system shows a reversible equilibrium between the aggregate and its dissociated species in
solution. Such equilibrium control of the host-guest system is reminiscent of left and right ball-and-
socket joint behavior.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: INOR1-2
: New Visions in Organometallics and Nanochemistry
: , : 09:25, :
Nanostructured Bulk Thermoelectric Materials for Energy Harvesting
Applications
Upon confronting present energetic and environmental challenges, the global need for utilizing exhausted
waste heat has been accelerated. In effect, thermoelectric materials are gathering a great interest as a
potential alternative energy source because of their capability of direct energy conversion between heat
and electricity. The increase of thermoelectric efficiencies is one of the main challenges of our scientific
community. The performance of a thermoelectric material is assessed with the figure of merit ZT defined
as (S2????/k)T; where S is the Seebeck coefficient (or thermopower), ???? electrical conductivity,
thermal conductivity, and T is the temperature. Recent theoretical and experimental studies show that the
use of thermoelectric materials comprising nanostructured components increases ZT relative to that of the
bulk counterparts of these materials. Minimizing thermal conductivity while maintaining the electrical
conductivity is the key point in formation of nanoscaled or nanocomposite thermoelectric. Controlling the
size and content of the nanoscale constituents within the bulk materials is especially important to achieve
high ZT. Thus, new routes for the preparation of these components as nanoscale powders are essential for
incorporating them as nanoscale constituents of the bulk materials. In this presentation, an overview of
recent advances in the development of high performance nanoscaled thermoelectric materials.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: INOR1-3
: New Visions in Organometallics and Nanochemistry
: , : 09:50, :
Electrical Activation of Mg-doped GaN Epitaxial Layer by
Electrochemical Method
GaN Optoelectric
n-type GaN p-type GaN . n-GaN
, p-GaN n-GaN ~10% . p-GaN
, GaN
, p-GaN .
p-GaN . p-GaN
Mg-H complex , dangling bond hole
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,
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. LED Near-UV LED , LED ~30%
. Leakage
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: INOR1-4
: New Visions in Organometallics and Nanochemistry
: , : 10:15, :
Facet-controlled alloy nanoparticles: Design, Synthesis, and
Application
Alloying and dealloying behaviors in the nanoscale particles are greatly different from those of bulk
materials, because the surface energy of nanoparticles is significant in determining the overall particle
energy. We have been particularly interested in the alloy formation in the facet nanoparticles; facet-
controlled nanoparticles can now generate geometrically precise energy gradients within the entire
nanoparticle and therefore geometrically-predetermined phase segregation is now feasible. Herein I
present our recent efforts in the nanoscale alloy formation and nanoparticle-specific reactivities with the
ultimate goal of development of atom efficient and highly active nanocatalysts for energy applications.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: INOR1-5
: New Visions in Organometallics and Nanochemistry
: , : 10:50, :
Improved Photoelectrochemical Water Splitting Efficiency by the
Formation of Metal Oxide Composite
Artificial photosynthetic systems are promising approaches to convert sunlight into chemical fuels.The
most popular strategy is photoelectrochemical (PEC) water splitting to produce hydrogen sustainably.
Metal oxide composites, typically comprising a primary photon absorbing semiconductor with a
secondary semiconductor that may play a number of assisting roles, are constructed using various
materials to elucidate the processes of electron-hole separation and charge transport through the
composite. These composite structures are divided into four different configurations depending on the
possible electron-hole separation mechanism. These systems elucidate the effect of conduction and
valence band positions of the individual components of composite materials.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: INOR1-7
: New Visions in Organometallics and Nanochemistry
: , : 11:20, :
-
()(KAIST)
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: INOR2-1
: Recent Advances in Organometallic Chemistry
: , : 13:30, :
N-Heterocyclic Carbenes Mimicking Transition Metal Complexes
(POSTECH)
N-heterocyclic carbenes (NHCs) are well-known to stabilize main group radicals and radical ions.
Pioneered by the Bertrand and other groups, phosphoryl, silyl, boryl and other organic radicals stabilized
by NHCs have been isolated and characterized. A successful preparation of the radical compounds was
explained by NHCs pi-acceptor character, which imparts remarkable stability because the significant
portion of the spin density of the radicals resides on the carbene carbon. We found that NHCs could
stabilize nitric oxide (NO) radical in a solution phase to form stable NHC NO radicals. Although nitrous
oxide was dominantly formed during the thermolysis of NHC nitric oxide compounds, nitric oxide was
also found to be thermally transferred to other N-heterocyclic carbenes. This suggests potential biological
applications for NO delivery. Furthermore, this study adds another example of stable singlet carbenes
acting as mimics for transition metal centers. Further studies on carbenes reactivity with other small
molecules will deepen our understanding of this interesting resemblance. Full characterization of the
compounds including X-ray crystallography, EPR, UV-vis, and cyclic voltammetry will be presented in
addition to the mechanistic studies and NO transfer experiments.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: INOR2-2
: Recent Advances in Organometallic Chemistry
: , : 14:00, :
Cycloaddition of Carbon Dioxide to Epoxides Using Catalysts
Cyclic carbonates could be easily synthesized via the cycloaddition of CO2 to epoxides, and they could be
widely used as polar aprotic solvents, electrolytes for lithium ion batteries, and precursors for
polycarbonates, enantiopure aminoalcohols, thermosetting coatings, and pharmaceutical intermediate. For
the synthesis of cyclic carbonates, many examples of homogeneous catalytic systems were reported in the
literature. The new advances of catalysts such as metal-based and metal-free compounds for
cycloaddition reaction will be presented. Acknowledgment: This work was financially supported by the
Korean Ministry of Education (MOE) and the National Research Foundation of Korea (NRF) through the
Creative Human Resource Training Project for Regional Innovation (grant number 2014H1C1A1066874).
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: INOR2-3
: Recent Advances in Organometallic Chemistry
: , : 15:00, :
Briphos: A New Class of -Acceptor Ligand Induced by Geometrical
Constraints
(KAIST)
There has been continuing interest in transition metal catalysis: it is hoped that these reactions will help in
the development of unprecedented chemical reactions as well as to providing green chemical processes in
the pharmaceutical and find-chemical industries. Indeed, the catalytic performance of the studied
transition metals highly depends on the character of the ligands that bind to the central metal atoms. Thus
the investigation of ligand effects has been one of the major research topics in the field of transition metal
catalysis.We here report a new class of bicyclic bridgehead phosphoramidite (briphos) ligand based on
the bicyclo[3,3,1]nonane structure. We show that the geometrical constraints in briphos with respect to its
linear analogs enhance -acceptor ability. Furthermore, facile tuning of briphos leads to highly efficient
ligands showing dramatic ligand acceleration effect (LAE), new catalytic reactivity in Rh(I)-catalyzed
conjugate additions of aryl boronic acids.The design of briphos ligand is based on our observation that
internal hydrogen bonds significantly promote the imine formation of benzophenone and the imine
products have been used for stereoselective generation of axial compounds and chiral-at-metal
complexes.Reference1. Lee, A.; Ahn, S.; Kang, K.; Seo, M.-S.; Kim, Y.; Kim, W. Y.; Kim, H. Org. Lett.
2014, 16, 54902. Seo, M.-S., Lee, A., Kim, H. Org. Lett. 2014, 16, 2950 3. Seo, M.-S., Kim, K., Kim, H.
Chem. Comm. 2013, 49, 11623
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: INOR2-4
: Recent Advances in Organometallic Chemistry
: , : 15:30, :
Organometallic compounds of transition metals and/or main group
metals for precise polymerization of olefin and/or styrene
*
Organolithium compounds were efficiently utilized in the construction of various transition metal
complexes for olefin polymerizations in our laboratory. Complexes 1-3 exhibited high activity, high 1-
octene incorporation, and high molecular weight in ethylene/1-octene copolymerizations. Complexes 4
and 5 showed excellent catalytic performances in 1-decene oligomerizations for lubricant basestock and
in ethylene/norbornene copolymerizations, respectively. Recently, we expanded utilization of the main
group organometallic compounds, alkyllithium and dialkylzinc, to the area of "catalyzed chain growth" to
construct polyolefin-block-polystyrene.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PHYS1-1
: Biophysical Chemistry: Biological Phenomena Viewed by Physical Chemistry
: , : 09:00, :
Computer Simulation Techniques in Biophysical Problems
With ever-increasing computational power and developments in user-friendly simulation software,
computer simulations have now become indispensible tools in studying biophysical problems including
enzyme catalysis, membrane structure and dynamics, and even cell functions. However, since biological
systems are still too complex to be studied by first-principle computational techniques, various levels of
approximations and techniques are employed depending on the systems of interest. In this talk, I will
briefly overview currently available particle-based computer simulation techniques by introducing several
biophysical problems I have been investigating in recent years.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PHYS1-2
: Biophysical Chemistry: Biological Phenomena Viewed by Physical Chemistry
: , : 09:30, :
Implications of DNA sequence composition in the chromosome
structure and epigenetics
(UNIST)
The chromosome spends most of its lifetime in the interphase in which it is only loosely condensed and
hence viewed as a dynamic polymer. Its structure and dynamics globally affect the gene expression but it
is only recent that its average structure was presented through the Hi-C technique by showing the intra-
and inter-chromosomal contact map of the whole DNA. We recently discovered that the Hi-C contact
map highly and universally correlates with the local AT content. From all-atom molecular dynamics
simulations, we hypothesized that the polycation-driven condensation of the DNA explains such global
behavior. We proved the hypothesis by designing a simple in vitro system for the single molecule
measurement of dsDNA-to-dsDNA interaction.
-
115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PHYS1-3
: Biophysical Chemistry: Biological Phenomena Viewed by Physical Chemistry
: , : 10:00, :
Upconverting nanoparticles: a versatile platform for wide-field two-
photon microscopy
(GIST)
Lanthanide ion-doped upconversion nanoparticles (UCNPs), which emit in the visible range upon
absorption of NIR photons, have attracted great attention in the area of biological imaging owing to their
advantageous properties. First, two-photon upconversion of NIR excitation to the emission of a visible
photon is so efficient that a tiny CW laser with the output of tens of milliwatts is sufficient as the
excitation source even for single-particle detection. Therefore, inexpensive wide-field two-photon
imaging can easily be achieved with UCNPs, which is not possible with organic fluorophores and
femtosecond laser systems used in conventional two-photon microscopy. Second, by employing NIR
excitation, one can suppress cellular autofluorescence, hardly induce photo-damage to cells, and achieve
relatively deep penetration into tissues. In addition, UCNPs are extremely photo-stable without any
photoblinking and photobleaching, and finally, their cytotoxicity turns out to be very low. All these
aspects strongly suggests that the UCNP-based imaging should provide an excellent platform for non-
scanning wide-field two-photon microscopy, which is capable of high-speed, high-contrast,
biocompatible, uninterrupted, and long-term imaging. Such advanced concepts in microscopy were fully
demonstrated in our study on the real-time tracking of single UCNPs in live cells. Furthermore, we
employed this technique to investigate the mechanism of gene delivery, addressing the issues such as
DNA release, cell division.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PHYS1-4
: Biophysical Chemistry: Biological Phenomena Viewed by Physical Chemistry
: , : 10:40, :
Energetics and Dynamics of Transport of Ions and Biomolecules
through Cyclic Peptide Nanotubes
Cyclic peptide nanotubes (CPNs) are synthetic proteins which transport ions and biomolecules through
lipid bilayer membranes. We used molecular dynamics (MD) simulations to calculate potential of mean
force (PMF), position-dependent diffusion coefficients, and force autocorrelation functions (FACs) for
ions and glucose through CPNs embedded in a DMPC lipid bilayer membrane.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PHYS1-5
: Biophysical Chemistry: Biological Phenomena Viewed by Physical Chemistry
: , : 11:10, :
Probing protein interactions and dynamics in a single living cell
(POSTECH) /
Dynamic interactions between membrane proteins and ligands determine correct cellular responses to
diverse environmental changes. Because various protein complexes on a plasma membrane participate in
cellular functions, technique identifying complex interactions of membrane proteins with spatio-temporal
resolution in a single living cell is highly demanding. Here I present an imaging technique of membrane
protein interactions that utilizes the accurate measurement of diffusion coefficient of membrane proteins
by tracking individual proteins in a single living cell. We validated this approach that can measure the
interactions between ligands and membrane proteins using an epidermal growth factor receptor and show
its applicability in measuring dissociation constant of ligands and mutant specific interactions in a single
living cell. We extended our technique to G protein-coupled receptors, which confirms the dissociation of
Gi-protein at the downstream of ligand interactions. Our results demonstrate that our approach would be a
powerful technique for investigating the various interactions of membrane proteins and the processes of
signal transduction in a single living cell.
-
115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PHYS1-6
: Biophysical Chemistry: Biological Phenomena Viewed by Physical Chemistry
: , : 11:40, :
NMR dynamics study of Z-DNA binding proteins and miRNAs
Left-handed Z-DNA is a higher energy conformation than B-DNA and is induced by high salt, negative
supercoiling, and complex formation with Z-DNA binding protein (ZBPs). ZBPs have been identified in
RNA editing enzyme (ADAR1), DNA-dependent activator of interferon regulatory factor (DAI), viral
E3L protein and protein kinase containing Z-DNA binding domains (PKZ). In this study, we determined
the solution structure of the free from of caZPKZ by multidimensional heteronuclear NMR spectroscopy.
We also performed NMR experiments on complexes of caZPKZ with DNA duplexes, dT(CG)3 and
d(CG)3 under various NaCl concentrations. We investigated changes in the conformation and dynamics
of caZPKZ induced by increment of NaCl concentration. Comparison of these results to that of ZADAR1
provides the molecular basis for B?Z transition mechanism of ZBPs, which is modulated by
conformational dynamics of a key tyrosine residue in the 3 helix.In plants, the DCL1 enzyme processed
primary miR156a into miR156a/miR156a* duplex via a loop-to-base processing mecanism. Some pairing
mutants on the B5 bulge (P-B5 mutants) caused earlier flowering than wild-type pri-miR156a. Here, we
have investigated the structural and/or dynamics changes of the miR/miR* duplex region induced by P-
B5 mutations. This study provides insight into the molecular mechanism on the second cleavage reaction
at lower stem structure by DCL1.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PHYS2-1
: Recent Trends in Physical Chemistry
: , : 13:25, :
Something happening in a non-adiabatic region: A proton-coupled
electron-transfer case
A brief description on the backgrounds leading to the interests about non-adiabatic regions of chemical
changes will be followed by discussions on detailed dynamics of a proton-coupled electron-transfer
(PCET) process as a representative case of the non-adiabatic regions. To capture the 'microscopic yet
dynamical view' of the non-adiabatic stage, the time-dependent quantum wave-packet propagation
method in conjunction with high-level electron correlation theories, MRCI and IP-EOM-CC methods,
was applied to the dynamics of the charge-transfer (CT) excited state of FHCl corresponding to F+HCl-.
The dynamics of this CT state, generated by the photo-detachment of an electron from the precursor anion
FHCl-, corresponds to a bidirectional PCET with two dissociation channels: the electron transfer (ET,
generating FH and Cl) and proton transfer (PT, generating F and HCl) paths. Calculated branching ratio
of ET/PT disclosed a surprising fact that PT prevail over ET. More importantly, a detailed analysis of the
non-adiabatic region suggests that the proton movement starts about 3 femto-seconds earlier than the net
adjustment of electrons distribution, and the electron adjustment is triggered by the initial movement of
the proton. A few more model systems of X-H-Y will be discussed too, and some comments on recent
researches related to this topic will be made as a closing remark.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PHYS2-2
: Recent Trends in Physical Chemistry
: , : 13:45, :
Transient Chemical Species : A Study of Reaction Dynamics and
Applications
Two topics related to transient organic species will be presented.
a) Atom-radical reaction dynamics: Oxidation reaction dynamics of a series of hydrocarbon radicals has
been examined as prototypal radical-radical oxidation reactions. High-resolution laser spectroscopy in a
crossed-beam configuration was applied to examine the nascent rovibrational state distributions and
Doppler profiles of the reactive scattering products. The analyses of the product energy and population
distributions demonstrated the existence of unusual dynamic characteristics and competition between the
addition and abstraction reaction mechanisms at the molecular level. These features in sharp contrast with
those of the oxidation reactions of closed-shell hydrocarbon molecules will be discussed with the aid of
the ab initio and quantum statistical calculations.
b) Organic electronic devices Semiconducting -conjugated organic clusters were utilized to prepare the
various organic devices such as OFETs (Organic Field-effect Transistors), OLEFETs (Organic Light-
Emitting Field Effect Transistors), inverters, etc. The weakly bound and highly directional neutral cluster
beams were quite efficient in producing the high-quality thin films leading to significant improvements in
surface morphology, crystallinity and packing density at room temperature. The OFETs and OLEFETs
demonstrated good field-effect characteristics, stress-free operational stability, and electroluminescence
under ambient conditions. In the cases of organic CMOS inverters ideal performance was realized by
integration of unipolar OFETs.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PHYS2-3
: Recent Trends in Physical Chemistry
: , : 14:05, :
Femtosecond X-ray liquidography captures the formation of chemical
bond in the solution phase
(KAIST)
The pump-probe X-ray diffraction and scattering techniques have now been fully established as a
powerful method to investigate molecular structural dynamics [1-5]. We have employed the techniques to
study structural dynamics and spatiotemporal kinetics of many molecular systems including diatomic
molecules, haloalkanes, organometallic complexes and protein molecules over timescales from ps to
milliseconds. X-ray crystallography, the major structural tool to determine 3D structures of proteins, can
be extended to time-resolved X-ray crystallography with a laser-excitation and X-ray-probe scheme, but
has been limited to a few model systems due to the stringent prerequisites such as highly-ordered and
radiation-resistant single crystals. These problems can be overcome by applying time-resolved X-ray
diffraction directly to protein solutions rather than protein single crystals. To emphasize that structural
information can be obtained from the liquid phase, this time-resolved X-ray solution scattering technique
is named time-resolved X-ray liquidography (TRXL) in analogy to time-resolved X-ray crystallography
where the structural information of reaction intermediates is obtained from the crystalline phase. We will
present our recent results including the achievement of femtosecond TRXL by using an X-ray free
electron laser.[1] Direct observation of bond formation in solution with femtosecond X-ray scattering,
K. H. Kim, J. G. Kim, S. Nozawa, T. Sato, K. Y. Oang, T. W. Kim, H. Ki, J. Jo, S. Park, C. Song, T. Sato,
K. Ogawa, T. Togashi, K. Tono, M. Yabashi, T. Ishikawa, J. Kim, R. Ryoo, J. Kim, H. Ihee*, S. Adachi,
Nature, 2015, in press.[90] Volume-conserving trans-cis isomerization pathways in photoactive yellow
protein visualized by picosecond X-ray crystallography, Y. O. Jung, J. H. Lee, J. Kim, M. Schmidt, K.
Moffat, V. Srajer, H. Ihee*, Nat. Chem., 2013, 5, 212-220.[3] Visualizing Solution-Phase Reaction
Dynamics with Time-Resolved X-ray Liquidography, H. Ihee*, Acc. Chem. Res., 2009, 42, 356-366
(Review Article).[4] Tracking the structural dynamics of proteins in solution using time-resolved wide-
-
angle X-ray scattering, M. Cammarata*, M. Levantino, F. Schotte, P. A. Anfinrud, F. Ewald, J. Choi, A.
Cupane, M. Wulff, H. Ihee*, Nature Methods, 2008, 5, 881-887.[22] Ultrafast X-ray diffraction of
transient molecular structures in solution, H. Ihee*, M. Lorenc, T. K. Kim, Q. Y. Kong, M. Cammarata,
J. H. Lee, S. Bratos, M. Wulff, Science, 2005, 309, 1223-1227.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PHYS2-4
: Recent Trends in Physical Chemistry
: , : 14:30, :
Unprecedented colorimetric responses of polydiacetylene based
nanofibers
* 1 2
1 2
Polydiacetylene (PDA) polymers, which were typically prepared by UV irradiation, display unique the
blue to red color transition upon environmental stimulation. We report for the first time that
polydiacetylenes (PDAs) can be alternatively prepared via plasma induced polymerization process. The
degree of polymerization and color transitions could be manipulated by controlling the power of plasma
radio frequency, exposure time and by using acrylic mask. In the current study, 10, 12-pentacosadiynoic
acid (PCDA) monomers embedded electro-spun fibers, PCDA-HEG embedded fiber bearing
hexaethylene glycols (HEG) as head groups and their combinations were explored to study the steric
factors of head groups in color transition. We could also demonstrate that patterned colorimetric and
fluorometric images could be obtained through a simple acrylic mask with plasma. These results
demonstrate not only the first example of PDA polymerization via plasma but also a great potential of
plasma process to be used as patterning applications.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PHYS2-5
: Recent Trends in Physical Chemistry
: , : 15:05, :
Study on graphene nanoribbon and residual polymer on graphene
using Raman spectroscopy
.
.
defect density .
hexagonal graphene
.
tensile strain . :1. Yoon, W., Lee, Y., Jang, H.,
Jang, M., Kim, J. S., Lee, H. S., Im, S., Boo, D., Park, J., and Ju, S. -Y., Graphene Nanoribbons Formed
by a Sonochemical Graphene Unzipping using Flavin Mononucleotide as a Template, Carbon, 81, 629-
638 (2014, article).2. Koo, E. -H., and Ju, S. -Y., Role of Residual Polymer on Chemical Vapor Grown
Graphene by Raman Spectroscopy, Carbon, 86, 318-324 (2015, article).
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PHYS2-6
: Recent Trends in Physical Chemistry
: , : 15:30, :
Electron Transport Characteristics of Molecular & Nano Structures on
the Organic Electronic Devices
Organic electronic devices based on conjugated small molecules and nano structures have been
extensively investigated as promising building blocks for nanoscale optical and electronic devices, such
as organic light emitting diode (OLED), organic photovoltaic (OPV) solar cell, thin film field effect
transistors (OFET), sensor and molecular electronic devices. However, only the electron transfer can
reveal the desired device functions, which strongly depends on the electronic structures of molecular and
nano components. Therefore, it is very important to understand how electron flows in a molecular and
nano structures and how to manipulate the electron transport behaviors for the development of new
functional organic electronic materials. The electron transport behavior can be classified by the phase of
organic materials. If the organic electronic devices are composed of bulk solid states, such as crystal and
amorphous, the electron transport is governed by inter-molecular hopping mechanism based on the
Marcus theory. Whereas, on the single molecule and nanostructure, the electron transport can be
explained by the intra-molecular ballistic transfer mechanism based on Non-equilibrium Greens function
(NEGF) theory. Therefore, controlling the bulk and molecular properties, such as morphology, growth
direction, and physical and chemical properties, can allow us to design new functional organic electronic
devices.In this presentation, I would like to introduce designed molecular and nano structures, and their
characteristic electron transport behaviors for on the organic electronic devices.
-
115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: PHYS2-7
: Recent Trends in Physical Chemistry
: , : 15:55, :
Equilibrium Dynamics in Electrolytes of Li-Ion Battery Studied by
Ultrafast Pump-probe and Two-Dimensional IR Spectroscopy
Electrolytes are ubiquitous and indispensable in all electrochemical devices including electrolytic cells,
capacitors, fuel cells, or batteries. Moreover, their function is the same in devices for serving as the
medium for the ion transport between electrodes. The electrolyte determines how fast the energy could be
released by controlling the rate of mass flow within the battery. After making solid electrolyte interphase
on the carbonaceous anode, there is no decomposition in electrolyte and Li ion transport occurs through
electrolyte. Thus, it has been suggested that the solvation structures and dynamics of Li ions in liquid
electrolyte play an essential role to Li-based battery performance. To mimic commercial electrolyte
composition composed of carbonates, Li ion were dissolved in diethylcarbonate (DEC) and its solvation
behavior was observed with IR spectroscopy as well as time-resolved IR spectroscopies including IR
pump-probe and 2D-IR experiments. IR spectroscopic results combined with DFT study reveals the
possible solvation structure and major interaction site for Li ion. Subsequent 2D-IR experiments show
that there is fast equilibrium solvation dynamics around Li-ion, which might give some clues about the
molecular mechanism of Li ion transport through electrolyte.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: ANAL1-1
: Recent Trends in Separation Analysis I: Fundamentals
: , : 09:00, :
Analysis of polyethylene terephthalate (PET) by LC-MS and MALDI-
TOF
()
Polyethylene terephthalate (PET) is the most common thermoplastic polymer of the polyester resin family.
The PET polymer is used in fiber and stretch blown plastic bottles as well as high end films, especially
for the electro-optical application. Depending on the polymerization process and thermal treatment, the
PET shows different physical and chemical properties. This semi crystalline polymer contains wide range
of oligomers affecting the polymer properties in a different way. Thus it is strongly needed to extract and
identify the oligomer from the PET polymer and to investigate the detailed synthesized mechanism. In
this work we use the several extraction techniques and LC-MS as well as MALDI-TOF to analyze the
oligomers in detail. The cyclic and linear oligomers with molecular weight up to 7,000 are completely
identified. Thus using the separation and MASS spectrometry provides the sufficient valuable information
to improve the PET quality in a delicate manner.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: ANAL1-2
: Recent Trends in Separation Analysis I: Fundamentals
: , : 09:25, :
Recent trends in Sports Doping Control
(KIST)
In 1999, the International Olympic Committee (IOC) led the way to creating the World Anti-Doping
Agency (WADA) through a collective initiative of sport and governments. WADA seeks to foster a
doping-free culture in sport. It combines the resources of sport and government to enhance, supplement
and coordinate existing efforts to educate athletes about the harmful effects of doping, reinforce the ideal
of fair play and detect those who cheat themselves and their sport.The use of performance-enhancing
drugs in sport is cheating. They are associated with serious medical complications and, above all, their
use is illegal. Procedures to detect prohibited substances in sports have been in operation for many years
and the analytical techniques used currently detect minute traces of substances, which may have been
taken several weeks ago. In this presentation, the state of the art analytical instruments, technology and
various applications will be introduced for anti-doping purpose.This work was supported by Korea
Institute of Science and Technology.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: ANAL1-3
: Recent Trends in Separation Analysis I: Fundamentals
: , : 09:50, :
A Multi-Task, Multi-Dimensional Immunoaffinity Capillary
Electrophoresis for the Selective Purification and Characterization of
Protein Biomarkers in Biosamples
Norberto A. Guzman
Immuno-Engineering and Bioanalysis, Princeton Biochemicals, Inc., U.S.A.
The long-term survival of patients with chronic diseases, in particular cancer, is influenced significantly
by the detection of early-stage disease. Determination of accurate protein biomarkers in biological fluids
and cellular structures is of great value in early diagnosis of a disease, surveillance and asymptomatic
screening, and the most promising approach to improve prognosis. Biomarker-based companion
diagnostics are also becoming of great value in predicting response to treatment. Companion biomarkers
are designed to identify responsive patient sub-populations or those likely to experience adverse drug
effects. Using companion biomarkers yields safer and more efficacious drug products, reduces clinical
trials and development costs, improves post-marketing safety profiles and salvages therapies that
otherwise would not be granted approval. The advent of personalized medicine will require change in the
traditional paradigms for developing and commercializing new pharmaceutical products. Today, less than
1% of current drugs have a companion diagnostic, and 60% of the drugs in clinical trials have a
companion diagnostic in mind. Some drugs which have been withdrawn from market or Phase 3
development due to serious adverse events may have had a different fate if combined with a companion
diagnostic to identify responders or to closely monitor toxicity.
The proteome represents all the possible gene products of a cell. Any protein may exist in multiple forms
that vary within a particular cell or in different cells, because of modifications derived from co-
translational, post-translational, regulatory and degradative processes that affect protein structure,
localization, function and turnover. Therefore, a combination of proteomic techniques should be capable
to characterize all proteins in a biological system, including complex features, like isoforms, chemical or
enzymatic modifications, interactions and functional structures.
-
Immunoaffinity capillary electrophoresis (IACE), which benefits by using the power of highly selective
affinity capture agents with the high-resolving power of capillary electrophoresis (CE), has demonstrated
to be a useful tool for the isolation, separation, and quantification of proteins and peptides. When coupled
to one or more sensitive detectors, such as a laser-induced fluorescence detector (LIF) and/or a mass
spectrometer (MS), IACE is becoming an important tool for the characterization of proteins and peptides
present at a wide range of concentrations in simple and complex matrices. Furthermore, when IACE-LIF
and/or IACE-MS are coupled with artificial intelligence based pattern recognition systems, it could result
in a powerful tool to study early changes in the underlying pathophysiology of many diseases and toxic
conditions.
In this seminar I will discuss the use of a multi-dimensional, multi-task immuno-separation instrument
adapted to be coupled to one or more detectors, including a mass spectrometer, for the capture, separation,
quantification, and characterization of protein and peptides biomarkers in biological fluids, cell extracts
and exhaled breath. Furthermore, I will address the use of IACE for the analysis of isoforms, modified
proteins and peptides, degradants, and protein-drug conjugates. The IACE instrument can be
manufactured as a portable miniaturized point-of-care instrument to be used in doctors office,
ambulances, and remote locations.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: ANAL1-4
: Recent Trends in Separation Analysis I: Fundamentals
: , : 10:35, :
Sequential injection - capillary electrophoresis: Fundamental design
and applications
Michael Charles Breadmore Daniel Gstoettenmayer Adam J Gaudry Ala Alhusban Joan
Marc Cabot Leile Ranjbar Hong Heng See Petr Smjekal*
School of Chemistry, University of Tasmania, Australia
Traditional capillary electrophoresis instrumentals operate in the batch mode: the capillary is transferred
from one vial to another for flushing, injection and separation. This is advantageous because of the
flexibility and level of automated throughput that can be achieved, particularly for method development
and optimisation. However, it is also limited in the ability to couple with other processes streams. Flow-
based systems offer an alternative instrument design that makes it easier to achieve regular and routine
monitoring of a particular sample as a function of time. Here, the construction and capabilities of a
number of flow-based capillary electrophoresis systems based on sequential injection will be discussed.
Unique to this design is the ability to efficiently inject all ions from a specific sample volume under
stacking conditions to provide superior detection limits. Applications of these systems for water
monitoring, cell cultures and for homemade explosives will be discussed.
-
115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: ANAL1-5
: Recent Trends in Separation Analysis I: Fundamentals
: , : 11:10, :
Development of a Multiuple Channel Capillary Electrophoresis System
(KRISS)
Capillary electrophoresis (CE) features unique advantages of high separation efficiency and small sample
volume-requirement. In addition, instrumentation for electrophoretic separation is simple, which
facilitates implementation of multiple channel separation for high throughput analysis. We have devised a
sample introduction method that allows simultaneous introduction of multiple samples without the help of
individualized sample wells. In a hydrophobic environment created with a non-polar solvent, aqueous
samples attached at the tips of sample loaders autonomously form hydrophilic sample bridges with the
entrances of CE channels. The hydrophilic bridges not only prevent samples from dispersing toward
others but also maintain themselves against possible agitations. Therefore, samples are to be intendedly
introduced into the separation channels without interfering others, which renders highly simple apparatus
design acceptable. Our plan is to develop an automated multiple channel CE analysis system for high
throughput analysis of routine samples based on the unique sample introduction method. The goal of
development is to realize a highly competitive commercial instrument.
-
115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: ANAL1-6
: Recent Trends in Separation Analysis I: Fundamentals
: , : 11:35, :
The chemical structures of newely identified analogures of drugs in
adulterated foods
The various forms of dietary supplements have been developed, because consumer demand for dietary
supplements that support their new or continuing healthy lifestyle has increased steadily in recent years.
The various forms of analogues of erectile dysfunction and anti-obesity drugs in the dietary supplements
which produced to avoid skillfully the regulation of the Ministry of Food and Drug Safety have been
increased. Recently, the most widely prescribed drug, sibutramine, was withdrawn from the market.
However, phosphodiesterase-5 (PDE-5) inhibitors have been developed to treat erectile dysfunction (ED)
and various ED drugs such as sildenafil, tadalafil, vardenafil, and mirodenafil have come onto the market.
Some manufacturers dope synthetic drugs into these products to increase treatment efficacy. To date, the
57 analogues of drugs such as PDE-5 inhibitors and sibutramine in adulterated health food products have
been identified and our laboratory has been continuously identifying these kind of drugs. The 8 illegal
analogues of drugs identified in adulterated foods in 2013 to 2014 were registered in the Criteria and
Standards for Food by MFDS and the analogues are continuously being discovered. The 6 out of 8
newely identified analogues of drugs have been first reported in Korea. The structures of 8 analogues of
erectile dysfunction(ED) were consistent with a proproxyphenyl-linked sildenafil, an acetylated product
of aminotadalafil or methylated tadalafil, and the new analogues were also found as impurities in illegal
analogues of drugs. Many analogues of ED may exist because of their chemical structures and the
analogues are becoming increasingly diversified and sophisticated in terms of their products and
processes. Therefore, it is essential to continuously monitor existing and newly identified analogues of
ED, along with elucidating its structural characteristics.
-
115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: ANAL2-6
: Recent Trends in Separation Analysis II: Applications
: , : 15:45, :
Online MW sorting-based enzyme reactor for jumping over the
limitation of conventional shotgun proteomics
(KRISS)
In general proteomics, advanced mass spectrometry coupled with diverse liquid chromatography
techniques (LC-MS) has been considered as a fundamental way to both identify and quantify protein(s) of
interest in biological sample, as well as to study protein post-translational modifications (PTMs). To this
end, proteolytic preparation for protein sample, which is an essential step for bottom-up proteomic
analysis, is carried out by in-gel or in-solution digestion with various proteases. However, it is well
known that this step is generally labor-intensive and time-consuming (over 12 hours). In this presentation,
we introduce a microbore hollow fiber enzyme reactor (mHFER)-LC-MS platform developed recently for
online digestion with complementing the issues in general proteolytic preparation. Furthermore, we also
present a simple, ease-to-use, and online antibody-specific shotgun proteomics for understanding the
biological functions of protein PTMs study
-
115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: ANAL2-1
: Recent Trends in Separation Analysis II: Applications
: , : 13:30, :
Chemical profiling of various alkaloids in herbal medicines using pH
control liquid-liquid extraction and LC-ESI-tandem mass
spectrometry
Alkaloids with significant biological effects are frequently found to be the main constituents of various
herbal medicines. Several types of alkaloids extracted from Fangchi (F.) and Corydalisis (C.) species
were characterized using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-
ESI-MS/MS). These interesting compounds were extracted from F. and C. species by sonication with 70%
CH3OH, and the extract was partitioned at pH values of 2 and 12. LC chromatographic separation of
alkaloids were investigated on reversed-phase C18 column with pH variation and composition of mobile
phase. Separation of these alkaloids in herbal extracts was found to be significantly affected on mobile
phase composition using gradient elution. Chemical profiling of alkaloids in F. and C. species was
successfully obtained for the classification of geographic origins and quality evaluation of herbal
medicines. Eight-types of alkaloids (aporpine, protoberberine, tetrahydroprotoberberine,
benzylisoquinoline, protopine, phthalide, morpine, and bisbenzylisoquinoline) observed in herbal
medicines were analyzed by electrospray ionization tandem mass spectrometry in positive ion mode.
Several types of fragmentations such as inductive and -cleavage, retro-Diels-Alder cleavage,
imminolization process or simple bond cleavage were observed according to their structural
characteristics. These fragmentation patterns could enable to instantly classify the specific alkaloid type
in MS/MS spectra of various alkaloids. Based on the MS/MS fragmentations, some of new alkaloids were
observed in herbal medicines.
-
115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: ANAL2-2
: Recent Trends in Separation Analysis II: Applications
: , : 13:55, :
Direct Characterization of Glycosylated Proteins by Ultrahigh-
Performance Nano LC-MS/MS
* Lance Wells1
1The Complex Carbohydrate Research Center, The University of Georgia
Protein post-translational modification (PTM) increases the functional diversity of the proteome by the
covalent addition of proteins. Therefore, identifying and understanding PTMs is critical in the study of
protein bioscience. Protein glycosylation is acknowledged as one of the major post-translational
modifications, with significant effects on protein folding, conformation, stability and activity. The need to
characterize glycoproteins continues to increase as more irrefutable examples of the essential role that
covalent carbohydrates in the proteins play in biological processes and functions. The extant challenge of
glycobiology and glycotechnology is to approach the extremely low level of sensitivity, used for PTM
analysis over the protein identification.In this study, several biologically important proteomic samples
was analyzed by shotgun proteomics method, the resulting modified peptides are separated and detected
by ultrahigh-performance nano liquid chromatography-tandem mass spectrometry (nano LC-MS/MS).
We, for the first time, identified specific O-GlcNAc modification sites of Oct1 and O-linked
glycosylation site of Tango1 with the state-of-the-art nano LC-Orbitrap Fusion Tribrid mass spectrometer.
Additionally, we focused on the analysis of native glycopeptide of endopolygalacturonases (EPGs) from
Botryotinia fuckeliana and polygalacturonase inhibiting proteins (PGIPs) from Phaseolus vulgaris to
define their structural interaction. The reports offer comprehensive information for the glycosylation
characterization of the EPGs and PGIPs including site identification of glycan attachment,
microheterogeneity determination of glycosylation, and N- and O-linked glycan profiles.This work
presents an overview of the methods, which have been successfully applied to the detection of level-
limited glycopeptides in the glycoproteins.Key Words: Oct1, Tango1, PGIPs, EPGs, Glycosylation, Site
mapping, and Nano LC-MS/MS
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: ANAL2-3
: Recent Trends in Separation Analysis II: Applications
: , : 14:20, :
A novel derivatization method of free cyanide including cyanogen
chloride for the sensitive and rapid analysis of cyanide in chlorinated
drinking water by liquid chromatography-tandem mass spectrometry
A novel derivatization method of free cyanide (HCN + CN-) including cyanogen chloride in chlorinated
drinking water was developed with D-cysteine and hypochlorite. The optimum conditions (0.5 mM D-
cysteine, 0.5 mM hypochlorite, pH 4.5, and a reaction time of 10 min at room temperature) were
established by the variation of parameters. Cyanide (C13N15) was chosen as an internal standard. The
formed -thiocyanoalanine was directly injected into a liquid chromatography-tandem mass spectrometer
without any additional extraction or purification procedures. Under the established conditions, the limits
of detection and the limits of quantification were 0.07 ?g/L and 0.2 ?g/L, respectively, and the inter-day
relative standard deviation was less than 4% at concentrations of 4.0, 20.0, and 100.0 ?g/L. The method
was successfully applied to determine CN- in chlorinated water samples. The detected concentration
range and detection frequency of CN- were 0.20-8.42 ?g/L (14/24) in source drinking water and 0.21-
1.03 ?g/L (18/24) in chlorinated drinking water.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: ANAL2-4
: Recent Trends in Separation Analysis II: Applications
: , : 14:55, :
Determination of vaccenic and elaidic acid in commonly consumed
foods using a silver ion cartridge solid phase extraction method
coupled with GC GC-TOFMS
This study aimed to develop an analytical method for accurately estimating the ratio of vaccenic to elaidic
acid (V/E value). To estimate an accurate V/E value, a silver ion cartridge (SIC) solid phase extraction
(SPE) method was performed for removing cis-fatty acids. The removal efficiency of cis-fatty acids was
greater than 97.8%. However, the analytical values of total trans-fatty acids (TFAs) were not significantly
different between with SIC SPE method and without SIC SPE method. Comparison tests of the V/E
values produced by two different methods (without SIC SPE method and with SIC SPE method) using
comprehensive two-dimensional gas chromatography combined with time-of-flight mass spectrometry
(GC GC-TOFMS) were also carried out. Those two methods exhibited significant differences in the
estimated V/E values because removing cis-fatty acids affected the V/E value but did not affect the total
TFAs. The SIC SPE method coupled with GC GC-TOFMS suggested in this research is available to
estimate accurate V/E values in commonly consumed foods, such as margarines, milk products and beef
tallow.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: ANAL2-5
: Recent Trends in Separation Analysis II: Applications
: , : 15:20, :
Digital Microfluidics as a Versatile Bioanalysis Tool
(KRISS)
Digital microfluidics (DMF) is a fluid handling technique in which discrete droplets are manipulated on
the surface of an array of electrodes. In this talk, I will present two recent projects using solid samples on
a DMF device. First, I will describe the work integrating solid-phase microextraction (SPME) in DMF. In
the new system, a SPME fiber is used to extract analytes from a complex sample, and is then inserted into
a DMF device. Solvent droplets are then used to extract analytes from the fiber with continuous actuation,
followed by analysis with liquid chromatography and mass spectrometry. Compared to conventional
methods, the new technique allows for fast, efficient desorption of analytes from the SPME fiber using a
small volume of solvent. The miniaturized system allows for preconcentration of analytes and was
applied the analysis of steroid hormones in human urine. Second, I will describe our work implementing
magnetic particle-based immunoassays in DMF. To increase the assay throughput, a new platform
capable of performing complete immunoassays with minimal manual intervention was developed. This
instrument comprises three core components: a Pogo pin interface for digital microfluidic control, an
integrated photomultiplier tube for chemiluminescent detection, and an adjustable magnet for particle
separation. Using this automation system allowed for parallel sample processing and full factorial design
of experiments (DOE) optimization. Relative to macroscale methods, this DMF approach reduced reagent
volumes and analysis time, and moreover, this represents the first DOE optimization for immunoassays
implemented in a microfluidic system. I propose that these techniques have great potential for numerous
applications in bioanalysis and beyond.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: BIO1-1
: Infectious Disease Research in Biochemistry and Structural Biology
: , : 09:15, :
Foot-and-mouth disease virus: a major global agricultural problem in
need of antiviral therapy
Foot-and-mouth disease (FMD) is a highly contagious disease of the cloven-hoofed animals caused by the
foot-and-mouth disease virus (FMDV; family Picornaviridae; genus Aphthovirus). FMD is the most
economically important veterinary pathogen due to its highly infectious nature, ability to cause persistent
infection and long-term effects on the condition and productivity of the many animal species it affects.
Due to the enormous socioeconomic consequences related to an FMD incursion, the main concern of
FMD-free major livestock producing countries is to prevent the introduction of the virus and/or to rapidly
eradicate it in case of an outbreak. Although vaccines have been crucial in controlling and eradicating
FMD from some parts of the world, the disease still affects millions of animals around the globe and
remains as the most important veterinary disease limiting trade of animals and animal products. The use
of current FMD vaccines to induce early protection is limited; thus, alternative/supplementary methods to
rapidly reduce the spread of FMDV in outbreak situations are urgently needed. One possible alternative
would be the use of antiviral drugs in a vaccinated zone to control viral dissemination and fill the
immunity-gap between time of vaccination and development of protective immunity. Unfortunately,
there are not yet commercially available antiviral therapies for prevention or treatment of FMDV
infection. In this presentation, the current efforts to discover FMD-antiviral drugs will be reviewed to help
and provide insights to investigators for identification of potential therapeutics to fight against this
devastating animal disease.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: BIO1-2
: Infectious Disease Research in Biochemistry and Structural Biology
: , : 09:40, :
Regulating the regulators: Basic concept and clinical application for
PD-1/PD-L1 interaction
For more than 100 years, immunotherapy for infectious disease and cancer has played an ever-increasing
role as a therapeutic regimen even though there are not many approved drugs and regimens. Activating
the immune system for therapeutic benefit in infectious disease and cancer has long been a goal in
immunology and oncology. After repetitive failures, the tide has finally changed due to the success of
recent proof-of-concept clinical trials using antibodies to blockade immune inhibitory molecules such as
CTLA-4 and PD-1. These successes suggest that tolerance raised by immune suppressive
microenvironment is a major obstacle for immunotherapy and therefore, blocking the tolerance is the first
step to rejuvenate antigen-specific T cell immune responses. In this seminar, the basic concept of T cell
exhaustion and the role of inhibitory molecules expressed by the exhausted T cells and regulatory T cells.
In addition, a representative inhibitory molecule, PD-1, and its current clinical use to treat infectious
disease and cancer will be introduced. Finally, future strategy to enhance the efficacy of the regulator
blockade therapy will be discussed.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: BIO1-3
: Infectious Disease Research in Biochemistry and Structural Biology
: , : 10:05, :
Characterization and Lead optimization of a novel hepatitis C virus
inhibitor acting on early and late steps of the viral life cycle
Marc P. Windisch
Institut Pasteur Korea Hepatitis Research
Approx. 200 million patients Hepatitis are chronically infected with hepatitis C virus (HCV) and are at
risk of developing life threatening liver diseases. Until to date, there are obvious unmet medical needs
which encouraged us to identify, characterize and develop novel HCV interventions.
We devised strategies using the infectious HCV cell culture system and carried out a phenotypic, target-
free screening campaign. By excluding compounds active in the replicon system and including those
active on HCV E1/E2 mediated entry, we identified inhibitors interfering with early and late steps of the
HCV life cycle. A promising hit was selected and further characterized in order to determine the
mechanism of action, antiviral potency and to evaluate properties crucial for drug development.
By conducting time-of-addition experiments with this favorable hit compound, inhibition of attachment
and internalization of HCV particles was observed. In addition, cell-to-cell spread and the secretion of
infectious virions was inhibited, whereas HCV RNA secretion and density of viral particle was unaffected.
Furthermore, this potent (EC50 0.0005uM, CC50 >5uM) inhibitor is synergistic in combination with
selected direct acting antivirals and IFN-alpha, and viral drug resistance profiling revealed the HCV
glycoprotein E1 as putative molecular target. Concerning DMPK, amongst other properties, metabolic
stability, solubility, CYP inhibition and other PK properties are being evaluated and improved.
In summary, we identified and characterized a very potent novel inhibitor acting on early and late steps of
the HCV life cycle. A Lead optimization campaign has been initiated to further improve drug-like
properties and to evaluate in vivo efficacy in order to move towards preclinical studies.
-
115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: BIO1-4
: Infectious Disease Research in Biochemistry and Structural Biology
: , : 10:45, :
Recognition of Lipopolysaccharides by TLR4 and its Accessory
Proteins
(KAIST)
Lipopolysaccharide (LPS) is a bacterial glycolipid that is the major component of the outer membrane of
gram-negative bacteria. It serves as an early warning signal of infection by initiating a potent immune
response. Lipid A, the lipid part of the LPS, is responsible for the majority of the immunological activity
of LPS and binds to the cell surface receptor, TLR4-MD-2 heterodimer. LPS binds to the hydrophobic
pocket in MD-2 and induces the dimerization of TLR4. Efficient activation the TLR4 signal in vivo
requires accessory proteins, LBP and CD14. LBP is a serum glycoprotein that can extract LPS from
bacterial membranes or vesicles released from it. CD14 accepts a monomeric form of LPS from LBP and
delivers it to the TLR4-MD-2 complex. The structures of these LPS recognition proteins in a complex
with LPS and related molecules provide us insight into how our immune system recognizes bacterial
infections and initiates efficient defense mechanisms. I will summarize recent structural studies of these
LPS receptors and accessory proteins.
-
115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: BIO1-5
: Infectious Disease Research in Biochemistry and Structural Biology
: , : 11:10, :
Structure-guided discovery of a novel inhibitor against class C beta-
lactamases with extended substrate spectrum
The emergence and dissemination of drug-resistant pathogens are great threat to public health in the
world. The expression of beta-lactamases, which inactivate antibiotics, is a prevalent resistance
mechanism of bacteria to beta-lactam antibiotics. Therefore, the development of inhibitors against beta-
lactamases is a challenge to treat drug-resistant pathogens. Recently, a non-beta-lactam inhibitor against
class C beta-lactamases has been discovered in my lab. The chemical structure of this novel inhibitor is
different from those of existing inhibitors. In addition, this inhibitor exhibited an in vivo efficacy without
side-effects in mouse models. In this talk, I present the molecular features of this inhibitor.
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115 (The 115th General Meeting of the Korean Chemical Society)
: 2015 4 15~17(~) 3
: KINTEX
: BIO1-6
: Infectious Disease Research in Biochemistry and Structural Biology
: , : 11:35, :
Structural biology of cell-shape determining proteins from
Helicobacter pylori
Helicobacter pylori is the major human pathogen associated with various gastrointestinal diseases such as
gastritis, ulcer, and gastric cancer. Its colonization of the human gastric mucosa requires high motility,
which depends on the helical cell shape. At least seven cell shape-determining genes (csd1, csd2,
csd3/hdpA, ccmA, csd4, csd5, and csd6) have been identified in H. pylori. These proteins play key roles
in determining the cell shape through modifications of the cell-wall peptidoglycan by alteration of
crosslinking or by trimming of peptidoglycan muropeptides. To provide a framework for a better
understanding of their molecular functions and for the discovery of novel inhibitors that would prove
helpful in fighting infections by H. pylori, we are carrying out determination of their crystal structures by
X-ray crystallography. Csd4 is a Zn-dependent D,L-carboxypeptida