Department

Paul Rablen - Swarthmore College
Some Consequences and Applications of the Gauche Effect
Coffee & cookies before the seminar
Host - Lionel Goodman

Xumu Zhang - Penn State University
Developing a Toolbox for Asymmetric Catalytic Reactions
Coffee & cookies before the seminar
Host - Alan Goldman

Professor Marisa Kozlowski (University of Pennsylvania) will be our Colloquium Speaker presenting "Computer-Aided Design of Chiral Auxiliaries and Catalysts" Please note the special location!
host - Lawrence Williams

Professor William D. Jonesof Rochester University is presenting the departmental colloquium entitled "Mechanistic Inorganic Chemistry and Catalysis"
host - Alan Goldman

Hiroyuki Kageshima presents "Atomic processes involved in thermal oxide growth on Si"

The thermal oxide growth process on Si is quite important to fabricate any Si-based devices, even for future nano-devices. The process is generally thought to be constituted by two atomic processes; the oxygen diffusion through the oxide layer and the interfacial reaction between oxygen and substrate Si. We have studied the barrier height of the interfacial reaction from first-principles calculation, and found that the height is quite lower than that estimated from experiments. This suggests that the general understanding is too simple. We propose to include the interfacial Si emission process for the third process constituting the Si oxidation based on our first-principles calculations and reaction-diffusion theoretical studies. Our experimental efforts to clarify this Si emission process are also introduced.

Professor George Gokel from Washington University will be our Colloquium Speaker presenting "Synthetic Cation-Conducting Channels"
host - Ralph Warmuth

The BIOMAPS Institute and DIMACS will present the following seminar on
Wednesday, December 10:

Speaker: Reka Albert, Penn State University
Title: "Topology and robustness of the segment polarity gene network"
Time: Buffet Lunch at 12:30 P.M.; Seminar at 1:00 P.M.
Location: Hill Center (Busch Campus) Room 260

For additional information on this seminar and the speaker, please refer to
the BIOMAPS Web site at: http://www.biomaps.rutgers.edu/seminars.html.

The BioMaPS Institute Presents

Speaker: Tsvi Tlusty, Rockefeller University
Title: A Colorful Origin for the Genetic Code
Time:12:30 P.M. (BRING YOUR OWN LUNCH)
Location: Hill Center (Busch Campus) Room 260

Prasanna Reddy's dissertation is entitled Synthesis of Monocyclic and Bicyclic Peptides - A Study of Lactam-Bridged Beta-Endorphin Analogues and is the result of research performed under the supervision of Prof. John Taylor.

Title: "The Gauche Effect in 1,2-Difluoroethane. Hyperconjugation, Bent Bonds, and Steric Repulsion".
Advisor: Lionel Goodman

Professor Robert Moss will present a seminar on Tuesday, January 27, 2004. Further details to be provided in the near future.

Professor Michael Hecht will present a seminar Tuesday, February 3rd. 2004.

Talk title: "Structures and Functions of De Novo Proteins from Designed Combinatorial Libraries"

Abstract:

Combinatorial libraries of de novo amino acid sequences can provide a rich source of diversity for the discovery of novel proteins. Randomly generated sequences, however, rarely fold into well-ordered protein-like structures. To enhance the quality of a library, diversity must be focused into regions of sequence space consistent with well-folded structures. We have designed focused libraries of sequences by constraining the binary pattern of polar and nonpolar amino acids to favor structures that contain abundant secondary structure, while simultaneously burying hydrophobic side chains in the protein interior and exposing hydrophilic side chains to the surrounding solvent. Recently, in collaboration with Jean Baum’s lab, we determined the structure of a 102-residue de novo protein from a binary patterned library and found the experimentally determined structure is a well-ordered four-helix bundle (see figure) as specified by the initial design. This finding demonstrates that amino acid sequences that have neither been selected by evolution (in vivo or in vitro), nor designed by computer, can form native-like protein structures. Examples will be presented demonstrating how binary patterning was used to construct libraries of either alpha-helical or beta-sheet proteins. These libraries have successfully produced well-ordered structures, cofactor binding proteins, catalytically active enzymes, self-assembled monolayers, amyloid-like nanofibrils, prototype biosensors, and novel protein-based biomaterials.

Professor Frank Quina will present a seminar on Tuesday, February 10th, 2004. Details to follow in the near future.

Stanislav Y. Shvartsman - "Modeling and manipulating EGFR-mediated cell communication in development"

The Epidermal Growth Factor Receptor (EGFR) signaling network is an evolutionarily conserved regulator of epithelial tissues. Alterations in EGFR signaling lead to severe developmental defects and pathologies, including a
large number of cancers. At this time, there is a fairly extensive understanding of the mechanisms by which EGFR controls the physiology at the level of a single cell. The current challenge is to understand how this network operates in tissues. For this, it is necessary to integrate the information from genetic and cellular studies into predictive quantitative models. I will describe our recent work on computational analysis of EGFR-mediated pattern formation in epithelial layers. We are using the Drosophila egg development as an experimental system and focus on dorsoventral patterning.

Professor Carl Trindle will present a seminar on Tuesday, February 17, 2004.

Abstract: "When is a Hydrogen Bond Not a Hydrogen Bond?"

We all know what a hydrogen bond is* -- every droplet of water reminds us -- and it explains so economically such dramatic and significant phenomena that it is an essential part of our understanding of chemistry. As for every powerful notion, it is tempting to use it outside its proper context. We review theoretical characterization of the hydrogen bond and discuss the extension of the idea to CH..O interaction, providing some new examples. We address the question of hydrogen bonding in CH..Br systems, excited states and ionized systems, and offer alternative explanation for some phenomena hastily attributed to hydrogen bonding.

*IUPAC definition:
The hydrogen bond is a form of association between an electronegative atom and a hydrogen atom attached to a second, relatively electronegative atom. It is best considered as an electrostatic interaction, heightened by the small size of
hydrogen, which permits proximity of the interacting dipoles or charges. Both electronegative atoms are usually (but not necessarily) from the first row of the Periodic Table, i.e., N, O, or F. Hydrogen bonds may be intermolecular or
intramolecular. With a few exceptions, usually involving fluorine, the associated energies are less than 20-25 kJ mol-1
(5-6 kcal mol-1).

Center for Molecular Biophysics and Biophysical Chemistry

presents

Jonathan Widom
Dept. of Biochemistry, Molecular Biology and Cell Biology
Northwestern University

"Chromosome structure and gene regulation"
Website: http://widomlab1.biochem.northwestern.edu/~wdmgrp/

Date: Friday, Feb. 20, 2004
1:30 PM
Room 260, Wright-Rieman Laboratories
Busch Campus
Piscataway, NJ

For additional information:
Center for Molecular Biophysics & Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Alexander Greer will present a seminar on Tuesday, February 24, 2004.

Physical Organic Chemistry with a View Toward Chemical Evolutionary Processes

We are evaluating topics related to oxygen and sulfur chemistry, photochemistry, molecular toxicity, and chemical evolution with the idea that solutions to problems can result when different fields of discovery are brought together. We are interested with mechanistic questions of organic and natural substances, and with the application of physical-organic chemistry. Chemical processes involving oxygen can lead to unstable peroxides molecules such as three-membered ring dioxiranes 1-3. The stability of these heteroatom-containing dioxiranes varies widely, allowing new kinds of peroxide structure and reactivity to be explored. We have an interest in the mechanisms that arise from singlet oxygen (1O2), ozone, (O3), N-oxides, S-oxides, and other molecules that can transfer an oxygen atom regio- and stereoselectively.

A subject of interest to us is the historical order of chemicals and the progression of biochemical diversity. The insights into the emergence of chemicals of biotic origin could provide evolutionary biologists “chemical” tools to view the subject at the molecular level rather than one commonly based on organism morphology. Our recent investigation
of ortho fused polysulfanes will be described. A basic principle that may cause chemical evolution to select polysulfur structures is suggested since there exists an odd-even alternation in the stability of products, o-C6H4Sx (x = 1 to 8).

Center for Molecular Biophysics and Biophysical Chemistry

presents

Sidney M. Hecht
Department of Chemistry
University of Virginia

"Molecular recognition of DNA and RNA by bleomycin"
Website: http://www.virginia.edu/chem/people/faculty/hecht/

Date: Friday, Feb. 27, 2004
1:30 PM
Room 260, Wright-Rieman Laboratories
Busch Campus
Piscataway, NJ

For additional information:
Center for Molecular Biophysics & Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Richard Franck will present a seminar on Tuesday, March 3rd, 2004.

Abstract:

In the early 90's, a group at Kirin Pharmaceuticals, reported their results from screening lipohilic extracts from an Okinawan sponge, Agelas mauritianus. When their extracts were tested in mice, but not in cell culture, they found potent antitumor activity produced by glycolipids which they named the agelasphins. Structure-activity studies of materials available through synthesis revealed that a slightly simpler analog of the natural agelasphins, an alpha-O-galactosyl ceramide 2 named KRN7000 had the best activity. Since the initial discovery, hundreds of papers have shown that this glycolipid acts as a potent immunostimulant in many murine models of human disease. Today's seminar will describe our synthetic efforts that have produced an alpha-C-galactosyl ceramide analog 1 of KRN7000. Some of the immunology data for 1 obtained by our collaborators will also be described.

Professor mathew Halls will present a seminar on Tuesday, March 9th, 2004. Details to follow in the near future.

Center for Molecular Biophysics and Biophysical Chemistry

presents

Kenneth P. Murphy
Associate Professor
Dept. of Biochemistry
University of Iowa

"Charge and Salt Effects in Molecular Recognition: Implications for Drug Design"
Website: http://www.biochem.uiowa.edu/faculty/murphy/index.htm

Date: Friday, March 12, 2004
1:30 PM
Room 260, Wright-Rieman Laboratories
Busch Campus
Piscataway, NJ

For additional information:
Center for Molecular Biophysics & Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Dave Thompson will present a seminar on Tuesday, March 23, 2004.

Title of Talk: "Design, Synthesis, and Performance of Biofunctional Organic Materials for Protein Crystallization and Drug Delivery"

Center for Molecular Biophysics and Biophysical Chemistry

presents

Dinshaw J. Patel
Memorial Sloan-Kettering Cancer Center

“Structural biology of RNA interference”
Website: http://www.mskcc.org/mskcc/html/10831.cfm

Date: Friday, April 30, 2004

Professor David Blank will present a seminar on Tuesday, March 30th, 2004. Details to follow in the near future.

Center for Molecular Biophysics and Biophysical Chemistry

presents

Juli Feigon
Department of Chemistry and Biochemistry
University of California

"Biophysical studies of telomerase RNA structure and mutations linked to disease"
Website: http://www.biochemistry.ucla.edu/biochem/Faculty/Feigon/

Date: Friday, April 2, 2004
1:30 PM
Room 260, Wright-Rieman Laboratories
Busch Campus
Piscataway, NJ

For additional information:
Center for Molecular Biophysics & Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Roy Vagelos will present this year's Merck Lecture.

Peter Wolynes, Departments of Chemistry and Biochemistry, and Physics, UCSD

"Successes of the Energy Landscape Theory of Protein Folding"

Professor Nicola Spaldin will present a seminar entitled "Computational Design of Multifunctional Materials" on Tuesday, April 13, 2004.

Center for Molecular Biophysics and Biophysical Chemistry

presents

W. David Wilson
Georgia State University

“Recognition of the DNA minor groove: compound, DNA and solvent reorganization”
Website: http://chemistry.gsu.edu/faculty/Wilson/Wilson.html

Date: Friday, April 16, 2004

professor Felix Castellano will present a seminar on Monday, April 19th, 2004.

Professor Philip Garner will present a seminar on Tuesday, April 27th, 2004.

Abstract:

"Helical Nucleopeptides. A New Twist on Antisense Drug Design?"

A promising strategy for the treatment of disease involves antisense down-regulation of proteins implicated in the disease's etiology. However, currently employed antisense technologies have drawbacks related to bioavailability and specificity. We propose to overcome these chemical problems by using helical nucleopeptides (HNPs). HNPs are novel molecular constructs that merge the structural variability of proteins with the codified molecular recognition of nucleic acids. Importantly, one may alter HNP's chemical and biological properties independent of its ability to bind to nucleic acid. This capability makes HNP an ideal platform for drug development and distinguishes it from existing antisense modalities. In this lecture, I will describe our progress in this area.

--

Date: April 30, 2004

Program:

9:45 a.m. to 11:00 a.m.: Poster Symposium to be held in Rieman Foyer

11:00 a.m. to 12:00 p.m.: Jean Wilson Day Lecture to be held in Wright Auditorium

Guest speaker: Dr. Philip Furmanski, Executive Vice President of Academic Affairs at Rutgers University

Lecture Title: Translational Research: From the Laboratory to the Clinic and Back

12:00 to 12:30: Undergraduate Awards to be held in Wright Auditorium

12:30 to 1:30: Lunch for Participants to be held in Rieman Foyer

Center for Molecular Biophysics and Biophysical Chemistry

presents

Dinshaw J. Patel
Memorial Sloan-Kettering Cancer Center

“Structural biology of RNA interference”
Website: http://www.mskcc.org/mskcc/html/10831.cfm

Date: Friday, April 30, 2004

Professor Joe Fox will present a seminar on Tuesday, May 4th, 2004.

Please refer to talk abstract.

Please join Dr. Berman as she hosts Professors David and Jane Richardson (of Duke University) who will present their talk entitled "Validation Tools that can Make Your Structure Better" .

Talk Title: "Molecular Interactions and Dynamics in Liquids Probed by Ultrafast Spectroscopy"

Research Interests: My main research interest is to understand chemical reactions and relaxation phenomena in condensed phases, especially in liquids. Molecules in liquids interact with each other in a complex manner, and this complicated interaction is a source of various aspects of the dynamical behaviors in liquids. In order to understand chemical events in condensed phases including reactions in biological molecules, it is necessary to investigate fundamental properties in the condensed phases in a molecular level. Recent work has included studies of vibrational dynamics in peptides, cytochrome c, and transition metal complexes.

Dr. Heinz Roth will present his seminar entitled "Return electron transfer in radical ion pairs of triplet multiplicity" on Tuesday, September 7th, 2004. An abstract of his talk has been noted below for your reference:

Return Electron Transfer in Radical Ion Pairs OF Triplet Multiplicity

Heinz D. Roth

Department of Chemistry and Chemical Biology, Rutgers University,
610 Taylor Road, New Brunswick, N. J. 08854-8087 USA
roth@rutchem.rutgers.edu

Radical ion pairs generated by photo-induced electron transfer or by encounter of independently generated radical ions may populate reagent triplet states upon Return electron transfer (RET). Similarly, they may form adduct biradicals by bond formation in triplet radical ion pairs or adduct zwitterions by bond formation in singlet radical ion pairs. The efficiency of triplet RET is governed by 1) the free energies of singlet and triplet back electron transfer (BET) and 2) the relative topologies of the potential surfaces of parent molecule, radical ion, and accessible triplet states or biradicals. Recombination may be very efficient when the potential surfaces have similar geometries (e.g., for aromatic donors / acceptors) and a triplet state is energetically accessible. In contrast, recombination may be inefficient, when geometries and connectivities of the minima on the radical ion and triplet/biradical potential surfaces are significantly different.

The lecture will explore intra-pair reactions of selected triplet radical ion pairs, generated by photo-induced electron transfer, and illustrating different relationships between potential surfaces. The advantages and potential disadvantages of various spectroscopic techniques applied to probe these phenomena (luminescence, time-resolved optical spectroscopy, magnetic field effects, CIDNP spectroscopy, or optoacoustic calorimetry) will also be discussed.

REFERENCES
(1) H. D. Roth, in Handbook of Electron Transfer, V. Balzani, Ed., Wiley-VCH, 2001, 2, 55-132.
(2) H. D. Roth, in Reactive Intermediate Chemistry, Chapter 6, R. A. Moss, M. Jones, Jr., M. S. Platz, Eds., New York: Wiley, 2003, 205-272

Center for Molecular Biophysics and Biophysical Chemistry

presents

Gaetano T. Montelione
CABM and Department of Molecular Biology and Biochemistry
Rutgers University

"Structural Proteomics"
Website: http://www-nmr.cabm.rutgers.edu/

Date: Friday, September 10, 2004 - Noon (12:00 - 1:00 PM)
Room 010, CABM Bldg
679 Hoes Lane
Busch Campus, Piscataway, NJ

For additional information:
Center for Molecular Biophysics & Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Amit Chattopadhyay will present a seminar on Tuesday, September 14, 2004.

Seminar Title: "Wavelength-Selective Fluorescence: A Novel Approach to Monitor Organization and Dynamics of Mebranes and Proteins"

Professor Albert Padwa of Emory University will present a seminar on Monday, September 20, 2004.

Seminar Title: "Cascade Reactions of Alkaloid Synthesis"

Professor Kieron Burke will present a seminar on Tuesday, September 21, 2004.

Seminar Title: "Density Functional Theory in Chemistry: Successes, Failures, and Challenges"

Abstract:

I will review the basic concepts behind density functional theory (DFT), and discuss especially recent applications of time-dependent DFT, including electronic excitations, electron-molecule scattering, and transport through single molecules. I will avoid mathematical formalism.

Professor Taekjip Ha will present a seminar on Friday, September 24, 2004.

Seminar Title: "Untangling Folding and Catalysis of Single Ribozyme Molecules"

Please refer to talk abstract.

Center for Molecular Biophysics and Biophysical Chemistry

presents

Celia Schiffer
Biochemistry and Molecular Pharmacology
U. Massachusetts Medical School, Worcester Campus

"HIV Protease Drug Resistance"
Website:
http://www.umassmed.edu/bmp/faculty/schiffer.cfm

Date: Friday, September 24, 2004 - Noon (12:00 - 1:00 PM)
Room 010, CABM Bldg
679 Hoes Lane
Busch Campus, Piscataway, NJ

For additional information:
Center for Molecular Biophysics & Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Bradley Smith will present a seminar on Monday, September 27, 2004.

Professor Gene Hall will present a seminar on Tuesday, September 28, 2004.

Seminar Title: "From Diamonds to Reproductive Tissues: Applications of Micro Raman, XRF, and FTIR in Analytical Chemistry"

Abstract:

I will review the basic concepts behind density functional theory (DFT), and discuss especially recent applications of time-dependent DFT, including electronic excitations, electron-molecule scattering, and transport through single molecules. I will avoid mathematical formalism.

Professor Patricia Thiel will present a seminar on Wednesday, September 29, 2004.

Seminar Title: "Quasicrystals: Intellectual Beauty Meets Pratical Applications"

Professor Steven Bradforth will present a seminar on Tuesday, October 5, 2004.

Seminar Title: "Ultrafast photodetachment of simple anions in water: spectroscopy and dynamics of radical/electron pairs"

Please refer to talk abstract:

Professor Hideo Tomioka of Mie University will present a seminar on Friday, October 8, 2004*.
Seminar Title: Triplet Carbenes: From Fleeting Existence to Useful Molecular Units"

*Please note new location/time:
Location: WL-260
Time: 2:00 P.M.

Professor Branka Ladanyi will present a seminar on Tuesday, October 12, 2004.

Center for Molecular Biophysics and Biophysical Chemistry

presents

William L. Jorgensen
Department of Chemistry
Yale University

"Protein-Ligand Binding and Computer-Aided Drug Design"
Website: http://zarbi.chem.yale.edu

Date: Friday, October 15, 2004 - Noon (12:00 - 1:00 PM)
Room 010, CABM Bldg
679 Hoes Lane
Busch Campus, Piscataway, NJ

For additional information:
Center for Molecular Biophysics & Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Mark Kobrak will present a seminar on Tuesday, October 26, 2004.

Seminar Title: "Molecular Solvation in Ionic Liquids:  The Need for a New Cartoon"

Abstract will be provided in the near future.

Center for Molecular Biophysics and Biophysical Chemistry

presents

Richard Friesner
Department of Chemistry
Columbia University

"Computational Methods in Protein Structure Prediction"
Website: http://www.columbia.edu/cu/chemistry/fac-bios/friesner/faculty.html

Date: Friday, October 29, 2004 - Noon (12:00 - 1:00 PM)

Room 010, CABM Bldg
679 Hoes Lane
Busch Campus, Piscataway, NJ

For additional information:
Center for Molecular Biophysics & Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Gregory Dudley will present a seminar on Tuesday, November 2, 2004.

See abstract for further details.

Professor Karen Goldberg will present a seminar on Tuesday, November 9, 2004.

Seminar Title: "Mechanistic Studies of Reactions Related to Platinum Catalyzed Selective Alkene Oxidation"

An abstract will be provided in the near future.

Center for Molecular Biophysics and Biophysical Chemistry

presents

Sergei Borukhov
Department of Molecular Biology and Genetics
SUNY Downstate Medical Center

"Prokaryotic transcription elongation factors Gre: structure-function and molecular mechanism of action"
Website: http://www.downstate.edu/molecularbiology_genetics/s.borukhov.html

Date: Friday, November 12, 2004 - Noon (12:00 - 1:00 PM)
Room 010, CABM Bldg
679 Hoes Lane
Busch Campus, Piscataway, NJ

For additional information:
Center for Molecular Biophysics and Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Nancy Levinger will present a seminar on Tuesday, November 16, 2004.

Seminar Title: "Probing water confined in reverse micelles through quasielastic neutron scattering and molecular dynamics simulations"

An abstract will provided in the near future.

Professor Max Di Ventra will present a seminar on Tuesday, November 23, 2004.

Seminar Title: "Transport in molecular structures: an overview of present understanding"

An abstract will be provided in the near future.

Professor Edward Arnold will present a seminar on Tuesday, November 30, 2004.

Seminar Title: "Aiming at a moving target: structure-based drug and vaccine design against HIV/AIDS"

An abstract will be provided in the near future.

Professor Mark Maroncelli will present a seminar on Tuesday, December 7, 2004.

Seminar Title: "Solvation in unusual (but friendly) environments: supercritical fluids and ionic liquids"

An abstract will be provided in the near future.

Center for Molecular Biophysics and Biophysical Chemistry

presents

Ann Stock
UMDNJ-Robert Wood Johnson Medical School and the Howard Hughes Medical Institute

Website: http://stock.cabm.rutgers.edu

Date: Friday, December10, 2004 - Noon (12:00 - 1:00 PM)
Room 010, CABM Bldg
679 Hoes Lane
Busch Campus, Piscataway, NJ

For additional information:
Center for Molecular Biophysics and Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Matt McIntosh will present a seminar on Tuesday, December 14, 2004.

Seminar Title: "Progress toward the Synthesis of the Eunicellin Diterpenes"

An abstract will be provided in the near future.

Professor Helen Berman will present a seminar on Tuesday, January 18, 2005.

Seminar Title: "Probing the Protein Data Bank"

Professor Ted Madey will present a seminar on Tuesday, January 25, 2005.

Seminar Title: "Surface Science from the Nanometer to the Kilometer Range"

Professor Jeffrey Aube will present a seminar on Tuesday, February 1, 2005.

Seminar Title: "New Reactions of Alkyl Azides in Synthesis"

Center for Molecular Biophysics and Biophysical Chemistry

presents

Allen Minton
Laboratory of Biochemistry and Genetics
NIDDK, National Institutes of Health

"Effects of macromolecular crowding upon protein stability and association: theory and experiment"
Website: http://www.niddk.nih.gov/intram/faculty.asp?People_ID=1519

Date: Friday, February 4, 2004 - Noon (12:00 - 1:00 PM)
Room 010, CABM Bldg
679 Hoes Lane
Busch Campus, Piscataway, NJ

For additional information:
Center for Molecular Biophysics & Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Neimark will present a seminar on Tuesday, February 8, 2005.

Seminar Title: "Phase Transitions and Nucleation in Nanoscale Systems"

An abstract will be provided in the near future.

Professor Chen will present a seminar on Tuesday, February 15, 2005.

Seminar Title: Interacting Partners for eIF-5A, an Essential Protein for Cell Survival and Proliferation"

An abstract will be provided in the near future.

Professor Xiaowei Zhuang will present a seminar on Tuesday, February 22, 2005.

Seminar Title: "Single-molecule and Single-virus Imaging in Vitro and in Live Cells"

An abstract will be provided in the near future.

Professor Herschel Rabitz will present a seminar on Tuesday, March 1, 2005.

Seminar Title: "Controlling Quantum Dynamics Phenomena with Shaped Laser Pulses Acting as Photonic Reagents"

An abstract will be provided in the near future.

Professor Kristi Kiick will present a seminar on Tuesday, March 8, 2005.

Seminar Title "Bioinspired Strategies for the Production of Multifunctional Materials"

Abstract:

In order to develop materials that can elicit specific responses to chemical and biological stimuli, it has become increasingly important to understand critical design features that control the structure, function, and assembly of macromolecules. Such understanding may permit the design of novel and functional biomolecular structures that are capable of selectively and efficiently interacting with cellular and other targets and/or directing materials properties. In the Kiick group, genetically directed methods are being employed to produce artificial repetitive proteins capable of controlled presentation of saccharides, peptides, and/or electroactive groups. The well-defined protein polymers produced via these methods exhibit desired and controlled conformational behavior and are being used to study biological phenomena such as the role of polymer architecture in mediating biological binding events, as well as materials phenomena such as the impact of polymer architecture on luminescence or the impact of protein surfaces on the growth of material substrates. We are also exploring the use of biologically relevant protein-saccharide interactions as a mechanism for controlling network formation and degradation in drug delivery matrices. Significant opportunities exist for utilizing these architectures for understanding mechanisms of cellular interactions with materials surfaces and for developing networks with controlled properties useful for biomaterials applications. Ultimately, our goals are not only to understand the macromolecular structure-function relationships that govern materials properties, but also to produce macromolecules with uniquely optimized properties for specific applications.

Center for Molecular Biophysics and Biophysical Chemistry

presents

Gary Pielak
Department of Chemistry
University of North Carolina at Chapel Hill

In-cell protein NMR
Website: http://www.chem.unc.edu/people/faculty/pielakgj/gjpindex.html

Date: Friday, March 11, 2004 - Noon (12:00 – 1:00 PM)
Room 010, CABM Bldg
679 Hoes Lane
Busch Campus, Piscataway, NJ

For additional information:
Center for Molecular Biophysics & Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Travis Holman will present a seminar on Tuesday, March 22, 2005.

Seminar Title: "Cryptophane Molecular Containers: Molecular Recognition to Materials"

An abstract will be provided in the near future.

Center for Molecular Biophysics and Biophysical Chemistry

presents

Eddy Arnold
Department of Chemistry
Rutgers University

"Unexpected "mob" behavior of hydrophobic drugs: Aggregation of some novel anti-AIDS drugs explains their superb bioavailability and clinical potency"
Website: http://lifesci.rutgers.edu/~molbiosci/Professors/arnold.html

Date: Thursday, March 24, 2004 - Noon (12:00 - 1:00 PM)

For additional information:
Center for Molecular Biophysics & Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Room 010, CABM Bldg
679 Hoes Lane
Busch Campus, Piscataway, NJ

Professor Filipp Furche will present a seminar on Tuesday, March 29, 2005.

Seminar Title: "Toward New Shores in Computational Photochemistry"

Abstract:

In photochemistry one takes advantage of the fact that the physical and chemical properties of a molecule may be completely altered by electronic excitation. Theory has traditionally played an important role in photochemistry, because it can establish a relation between the type of excitation (e.g. n-pi*) and the properties of the excited state. Moreover, electronically excited species are very difficult to characterize by experimental means due to their short lifetimes. Until recently, excited state calculations of useful accuracy were limited to ca. 10 electrons, which excluded most systems of chemical and biological interest. This has changed with the development of time-dependent density functional methods. I will start with a brief survey of concepts to compute excited states, and present benchmark results. Most of the talk will be devoted to applications which demonstrate the scope and the limitations of the present methodology. Examples will include CD spectra of beta-lactams, the photochemistry of 4-(dimethylamino)benzonitrile and other dually fluorescent molecules, andtriphenylaminosulfonium photoacids.

Professor Barry Trost will present this year's Merck Lecture on Monday, April 4, 2005.

Seminar Title: "On the Impact of New Synthetic Methods for the Synthesis of Bioactive Targets"

Professor Ed Stiefel will present a seminar on Tuesday, April 12, 2005.

Seminar Title: "Irony in Iron Metabolism: Scarcity, Toxicity, DNA Protection, Storage, and Evolution in Bacteria"

An abstract will be provided in the near future.

Professor Heather Maynard will present a seminar on Tuesday, April 19, 2005.

Seminar Title: "Synthesis of Bioconjugates by Controlled Radical Polymerization"

An abstract has been provided for your reference.

Center for Molecular Biophysics and Biophysical Chemistry

presents

Thomas Record
University of Wisconsin - Madison

Theme: Macromolecular Crowding
Website: http://www.biochem.wisc.edu/record/

Date: Thusday, April 21, 2004 - Noon (12:00 - 1:00 PM)
Room 010, CABM Bldg
679 Hoes Lane
Busch Campus, Piscataway, NJ

For additional information:
Center for Molecular Biophysics & Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Eugene A. Mash will present a seminar on Tuesday, April 26, 2005.

An abstract has been provided for your reference.

Center for Molecular Biophysics and Biophysical Chemistry

presents

John Johnson
Department of Molecular Biology

The Scripps Research Institute

Theme: Macromolecular Crowding
Website: http://lav.scripps.edu/

Date: Friday, April 29, 2004 - Noon (12:00 - 1:00 PM)
Room 010, CABM Bldg
679 Hoes Lane
Busch Campus, Piscataway, NJ

For additional information:
Center for Molecular Biophysics & Biophysical Chemistry
Phone: (732) 445-6376
E-Mail: mbcenter@rutchem.rutgers.edu

Center Events

Professor Professor Didier Astruc of The Universite Bordeaux, France, will present a special seminar on Monday, May 16, 2005.

An abstract will be provided in the near future.

Professor Dongyuan Zhao will present a seminar on Wednesday, June 15, 2005. See abstract for further details.

Professor Guy Bertrand will present a seminar on Wednesday, June 29, 2005. See abtract for further details.

Professor Guang-Yan Hong will present a seminar on Monday, July 11, 2005. The title of his talk will be "Synthesis and Applications of Rare Earth Nanomaterials". An abstract will be provided in the near future.

Professor Robert Glaser will present a seminar on Tuesday, September 6, 2005.

See abstract for further details.

Professor Kathryn Uhrich will present a seminar on Tuesday, September 13, 2005.

See abstract for further details.

Professor Michael Doyle will present a seminar on Monday, September 19, 2005.

An abstract will be provided in the near future.

Professor Rober McMahon will present a seminar on Monday, September 26, 2005.

Two articles relevant to Dr. McMahon's talk are noted below for review:

Astrophysical Journal Article

JACS Article

Professor Douglas English will present a seminar on Tuesday, September 27, 2005.

Please see abstract for further details.

Professor Haw Yang will present a seminar on Tuesday, October 4, 2005.

Please see abstract for further details.

Professor Edward Castner will present a seminar on Tuesday, October 11, 2005.

Talk title: "Interactions and Dynamics in Room Temperature Ionic Liquids"

Abstract:

Recent work in our laboratories has focused on understanding the physical and chemical properties of room temperature ionic liquids. These liquids are comprised of organic cations paired with either organic or inorganic anions. Ionic liquids are remarkable for their extremely low vapor pressures, making them relevant for many new chemical and industrial applications. Our studies of ionic liquids include characterizing several dynamical properties to study the interactions in ionic liquids. Experimental methods include studies of solvation dynamics and microviscosities (using time-resolved fluorescence), studies of intermolecular interactions and dynamics (using femtosecond optical Kerr effect spectroscopy), diffusion rates (by T1 and PFG-SE NMR measurements), and are combined with electronic structure calculations to understand the electrostatic interactions between the molecular ions.

I will discuss two recent aspects of our work on ionic liquids. We have successfully designed ionic liquids with reduced viscosities by substituting a trimethylsilylmethyl group for a neopentyl side group on the imidazolium cation of the ionic liquid. In a second project, we have synthesized the isoelectronic and isostructural neutral binary solution analog of an ionic liquid. This system permits us to investigate which properties result mainly from Coulombic interactions between the ions, and which from the complex interactions between components of a binary solution that have unlike sizes, shapes, and are highly polar and polarizable.

Professor Johnson will present a seminar on Tuesday, October 18, 2005.

Talk title: Polarity Reversal Catalysis: New Strategies and Applications

Abstract: This lecture will describe our recent efforts to employ acyl silanes as acyl anion equivalents. The discovery and development of metallophosphites as enantioselective umpolung catalysts for aldehyde and alkene acylation will be detailed.

Professor Ralf Warmuth will present a seminar on Tuesday, October 25, 2005.

See abstract for further details.

Professor Oleg Ozerov will present a seminar on Tuesday, November 1, 2005.

Talk title: "Pinching Metal Centers, Breaking Strong Bonds, and Catalysis"

Dr. Eugene Reynolds, Principal Scientist from Analytical Development at the Schering-Plough Research Institute, Union, NJ, will be recruiting on the Rutgers campus on Thursday November 3rd, during which time he will present a seminar entitled "Career Opportunities in the Pharmaceutical Sciences."

Dr. Reynolds is an alumnus of both our undergraduate program at Rutgers (RC'85) and our graduate program (PhD'92).

Refreshments will be served prior to the seminar presentation - All are welcome....

Professor Alice Ting will present a seminar on Tuesday, November 8, 2005.

Abstract to be provided in the near future.

Professor Younan Xia will present a seminar on Friday, November 11, 2005.

Talk Title:  "Self-Assembly of Spherical Colloids into Complex Structures"

Abstract to be provided in the near future.

Dr. Bruce Maryanoff will present a seminar on Tuesday, November 15, 2005.

Talk title: "Pyridine-Containing Macrocycles from the Cobalt-Mediated [2 + 2 + 2] Cycloaddition of Bis-Alkynes

Abstract: We have been investigating cobalt-mediated alkyne-nitrile co-cyclotrimerizations in the synthesis pyridine-containing macrocycles. For example, a long-chain bis-alkyne reacts with p-tolylnitrile to give a 1:1 mixture of meta- and para-pyridinophanes in 50-60% yield (see graphic). Conditions were developed to perform the reaction at 85-100°C, without irradiation, and without syringe-pump addition. Variation of the chain length was explored. Little or no ortho-disubstituted pyridine-macrocycles were formed. Para-pyridinone-cyclophanes were obtained selectively from related alkyne-isocyanate co-cyclotrimerizations. This [2 + 2 + 2] cycloaddition process has excellent atom-economy and, by forming a macrocycle and a heteroaromatic ring simultaneously, it delivers substantial molecular complexity in a single step.

Professor Shu Yang will present a seminar on Tuesday, November 29, 2005.

Talk title and abstract to be provided in the near future.

Dr. Oksana Cherniavskaya will visit the department on Monday, Dec 5, 2005 during which time she will present a seminar at entitled "Implementation of Nanoscale Arrays For Exploring Polyvalent Interactions In Cytoskeletal Proteins".

Professor Ka-Yee Lee will present a seminar on Tuesday, December 6, 2005.

Talk title: "Lipid-Protein Interactions at Interfaces: From Lung Surfactant to Poloxamer"

Abstract to be provided in the near future.

Professor Theresa Reineke will present a seminar on Tuesday, December 13, 2005.

Talk title: "New Polymeric Materials Designed for Nucleic Acid Delivery"

Abstract to be provided in the near future.

Dr. James Stambuli will visit the department on Thursday, January 5, 2006, during which time he will present a seminar entitled "Metal-catalyzed cross-coupling and cycloaddition reactions and Progress toward the synthesis of Beraprost".

Professor Evert Jan Baerends will present a seminar on Tuesday, January 24, 2006.

Talk Title: "Why rough surfaces make good catalysts:
Reaction mechanisms of hydrogen on the Pt(211) stepped surface"

See abstract for further details.

Dr. Rory Waterman will visit the department on Thursday, January 26, 2006, during which time he will present a seminar entitled "Mechanistic insights into and applications of alpha-elimination in element-element bond-forming reactions and catalysis."

Abstract: Bond-forming reactions such as dehydrocoupling are posited to proceed by a variety of mechanistic pathways. One route that remains largely unexplored is a-elimination, where a low valent main group fragment is extruded from a transition-metal center. In this work, the first examples of transition-metal catalyzed stibine dehydrocoupling are explored. The novel primary stibines, mesitylstibine and 2,6-dimesitylphenylstibine, are catalytically dehydrocoupled to Sb4Mes4 and dmpSb=Sbdmp, respectively, with liberation of dihydrogen by d0 hafnocene and zirconocene complexes. Mechanistic analysis shows the operant path to be a-stibinidene elimination followed by stibinidene condensation. Additional studies have shown a-elimination chemistry to be an increasingly general reaction type for main group ligands of early transition metals. This is in contrast to late transition-metal complexes, which favor a-migration.

The NJ Center for Biomaterials will host a seminar by Dr. James N. Cawse of the GE Global Research Center.

See below for further details.

Date: Friday, January 27, 2006

Time: 11:00 a.m.

Location: Life Sciences Auditorium

Talk Title: "Experimental Strategies for Combinatorial and High Throughput Materials Development"

Abstract: High throughput and combinatorial methods for materials discovery and optimization have presented a real challenge for the effective planning of experiments. When experiments can be run in parallel by the dozens or hundreds, the classic experimental designs for data-sparse systems must be rethought for data-rich ones. I discuss the newest developments in extensions of classical DOE's and mixture systems; evolutionary strategies; grid searches; and others in the context of basic data formats and assumptions about experimental space.

Dr. Suzanne Blum will visit the department on Monday, January 30, 2006, during which time she will present a seminar entitled "Ring-Opening Reactions Mediated by Zirconium Imido Complexes".

Professor Gregg Fields will present a seminar on Tuesday, January 31, 2006.

Talk title:  "Triple-Helical Model Systems for Dissecting the Mechanisms of Collagenolysis"

An abstract is noted below:

The hydrolysis of collagen (collagenolysis) is one of the committed steps in extracellular matrix turnover. Collagenolysis has been implicated in both normal tissue remodeling and a variety of diseases associated with abnormal turnover of extracellular matrix components. The triple-helical structure of collagen renders it resistant to most proteases. In vertebrates, the enzymes that cleave triple-helical structure include cathepsin K and collagenolytic matrix metalloproteinase (MMP) family members. The mechanism by which MMPs catabolize collagen is still largely unknown. Within the MMP family, there are also distinct preferences for collagen types. We have utilized a variety of triple-helical model systems, in combination with MMP mutants, to dissect the mechanisms of collagenolysis and better understand collagen specificities. The results to be presented indicate that substrate flexibility, MMP active sites, and MMP exosites all contribute to collagen degradation.

Professor Reiko Oda will present a seminar on Tuesday, February 7, 2006.

Talk Title:

An abstract is noted below:

Amphiphilic molecules self-assemble to form aggregates with extremely rich polymorphism and molecular structures have very important effect on the morphologies of these assemblies. We focus on the effect of counter-ions of cationic gemini surfactants on the structures of the aggregates and report various levels of organizations, i.e., from molecular to supramolecular to mesoscopic levels.

Professor Svetlana Sukhishvili will present a seminar on Tuesday, February 14, 2006.

Professor Roberto Car will present a seminar on Tuesday, February 21, 2006.

Talk Title: Kinetic Approach to Electron Transport in Nanoscale Devices

Abstract: A general theoretical framework to study electron transport at the nanoscale is presented. The approach is based on the Liouville-master equation for the electron reduced density operator and includes dissipative effects due to inelastic electron-phonon scattering. The Liouville-master equation is a fully quantum-mechanical approach that generalizes the semi-classical Boltzmann kinetic equation to spatial dimensions of the order of the electron wavelength. In this approach not only the tunneling structure and the contacts are treated explicitly but also the source of the current. After discussing some general physical consequences of dissipative effects I will present numerical applications to molecular structures and carbon nanotubes connected to metallic electrodes.

Professor Floreancig will present a seminar on Tuesday, February 28, 2006.

Details to be provided in the near future.

Professor David Whitten will present a seminar on Tuesday, March 9, 2006.

Talk Title: "Fluorescent Conjugated Polyelectrolytes: Superquenching, Biosensing and Biocidal Activity"

Abstract: The talk will focus on the photophysics of fluorescent conjugated polyelectrolytes and their very high sensitivity (superquenching) to quenching by small molecules that can associate with the polymers and interact via energy or electron transfer. The application of superquenching to biosensing has provided a means for high sensitivity detection of enzyme activity, proteins and nucleic acid hybridization. Very recent work has shown that superquenching assays can be carried out using flow cytometry and microfluidics. It has also been found that some of these polymers exhibit biocidal activity towards bacteria and bacterial spores. The origin of the light-induced biocidal activity will be discussed.

Professor Marina Petrukhina will present a seminar on Tuesday, March 21, 2006.

Talk Title: "Tuning the Reactivity and Coordination Limits of Open Geodesic Polyarenes"

Abstract: Study of the reactivity and coordination limits of open geodesic polyarenes (buckybowls), in which the inside and the outside carbon surfaces exhibit different properties, is a new area of research. An original and effective gas phase deposition approach is used in our group to tune ligating properties of buckybowls and to unravel novel aspects of their reactivity in metal binding reactions. Using co-deposition, we have successfully prepared the first metal complexes of corannulene,1 dibenzo[a,g]corannulene,2 and hemifullerene3 and revealed their preferences for metal binding. Importantly, multiple metal coordination to a bowl can be readily achieved under gas phase conditions to force rare polydentate bridging modes of polyarenes (Fig.). These investigations are focused at the fundamental metal--arene interactions with an emphasis on the perturbation of structure and reactivity induced by metal coordination to non-planar aromatic surfaces. Systematic investigation of such polyarenes should stimulate the use of curved carbon-rich molecules in materials synthesis. It should open new practical pathways for functionalization of unsaturated carbon surfaces and for controlled preparation of endo-complexes of fullerenes and nanotubes that are very desirable targets for a variety of practical applications.

Professor Roumiana Tsenkova of Kobe University, Japan will present a special seminar TODAY, WEDNESDAY, MARCH 22, 2006 in Wright-Reiman 260 from 3:30 PM to 4:30 PM.

Professor Tsenkova is the recipient of the prestigious 2006 Tomas P. Hirschfeld Award. The title of her talk will be "Light Upon The Waters in Action: NIR Perturbation Spectroscopy Reveals Peculiarities of biological Systems." An abstract has been noted below for your reference.

Abstract:

Water has often been described as “the greatest enemy” of IR spectroscopy and avoided as a strong interference. Recently, various studies on a single or a small number of water molecules have identified absorbance bands of numerous water species, in IR range. Further on, we proved that the main absorbance bands of water and its overtones cover mostly the whole VIS/NIR range. On the other hand, water is the most substantial, though not yet well understood, component of the biological systems. High population of water molecules in bio systems explains the visual similarity of their spectra. We report a new concept, which presents NIR light - water interaction as an extremely valuable source of information.

Water structure in biological system is very easily influenced by various factors. VIS/NIRS allowed non-destructive spectral acquisition, in real time, under various perturbations like time, temperature, optical path length, dilution, consecutive illuminations, dilution, etc. Water spectral changes under perturbations revealed peculiarities of the observed system. It was found that there was consistency of the band assignment with the reported results from IR water studies and our calculations. In each bio system, water matrix changed in different ways with each perturbation depending on the rest of the molecules surrounded by water and their structure. These results brought the idea to call VIS/NIRS “the best friend” of water. The analysis of the water matrix, under perturbations and VIS/NIR light, appeared as a new analytical method, which we called “Extended Water Mirror Approach” (EWMA). Further on, perturbation specific water absorbance patterns (WAPs) were found for various bio systems and their respective conditions.

WAPs were utilized in series of experiments. Increased accuracy was reported when perturbations were employed for composition measurements of elements in small concentrations. WAPs were defined and successfully used for disease diagnosis (mammary inflammation, oxidative stress, prion disease) and for identification of bacteria, genetically modified objects (GMO), etc. Based on these findings, we propose “Aqua-photomics” as a new discipline to utilize VIS/NIR perturbation spectroscopy for better understanding of the biological world.

Professor Nathan Lewis will present a seminar on Tuesday, March 28, 2006.

Talk title and abstract to be announced in the near future.

Professor Frank Weinhold will present a seminar on Tuesday, April 4, 2006.

Talk Title: "Natural Bond Orbital Picture of Valency, Bonding, and Torsional Phenomena"

Abstract: The Natural Bond Orbital (NBO) suite of wavefunction-analysis methods provides a general conceptual framework for picturing localized Lewis-like bonding interactions across the periodic table. The optimal NBO Lewis-like picture also provides the natural starting point for describing "resonance delocalization" effects in terms of general donor-acceptor interactions between filled (Lewis-type) and unfilled (non-Lewis-type) orbitals of the parent NBO structure. We summarize the general donor-acceptor paradigm for chemical bonding and the resulting heirarchy of n-electron/m-center bonding "types" (including some of highly unusual and surprising form), and we illustrate how the NBO donor-acceptor perspective yields a unified, coherent picture of many perplexing bonding and resonance-delocalization phenomena, including torsional and folding properties of complex biomolecules.

Professor David A. Evans will present this year's Merck Lecture on Thursday, April 6, 2006.

Seminar Title: "Studies in Organic Synthesis"

Professor Bill Roush will present a seminar on Tuesday, April 11, 2006.

Talk title and abstract to be announced in the near future.

Professor Jin Zhang will present an LSM Seminar on Thursday, 4/13/06. See abstract below for further details:

Talk Title: Novel Optical and Dynamic Properties and Emerging Applications of Semiconductor and Metal Nanomaterials

Abstract:

Nanomaterials are of strong interest for both fundamental and technological reasons. At the fundamental level, nanomaterials possess novel physical and chemical properties that differ from those of isolated atoms or molecules and bulk matter due to quantum confinement effects and exceedingly larger surface area relative to volume. These novel properties are highly promising for applications in emerging technologies such as nanoelectronics, nanophotonics, non-linear optics, miniaturized sensors and imaging devices, solar cells, and detectors.

Semiconductor nanoparticles have been studied extensively because of their potential application in electronic devices and the opportunity they offer to study the effects of quantum confinement. A unique subset of semiconductor nanoparticles is doped semiconductor nanoparticles. We have recently studied several doped semiconductor nanoparticle systems with the goal to understand the relation between their optical properties and the structure of the host nanoparticles as well as that of the dopant. In the case of Mn2+-doped ZnSe nanoparticles, we have found that the location of the Mn2+ significantly influences its optical emission properties. This understanding is important for designing new nanophotonics materials. We have also investigated the bioconjugation of silica-coated CdSe quantum dots to IgG proteins for potential applications in cancer biomarker detection and have found that the silica coating significantly enhance the stability of the CdSe quantum dots in buffer solutions based on photoluminescence properties.

Metal nanoparticles have also attracted considerable attention due to their interesting properties and potential applications. We have studied the optical and structural properties of different metal nanostructures including aggregates, nanorods, and nanoshells with the goal to optimize their SERS (surface-enhanced Raman scattering) activities. For example, we have very recently demonstrated SERS from single, hollow gold nanostructures. Exceptional sample homogeneity leads to a nearly tenfold increase in signal consistency over standard silver substrates. SERS offers a unique combination of molecular specificity and extremely high sensitivity that few other analytical techniques can offer. SERS based on metal nanoparticles, in conjunction with photoluminescence from semiconductor quantum dots, have been exploited for detection of cancer biomarkers.

Professor George O'Doherty will present a seminar on Monday, April 17, 2006.

See abstract as well as the below noted manuscripts for further details.

Manuscript 1

Manuscript 2

Professor Dean Tantillo will present a seminar on Tuesday, April 18, 2006.

Talk Title: "Carbocation Cascades in Natural Products Biosynthesis"

Abstract: Pentalenene is a sesquiterpene with three fused 5-membered rings and four adjacent stereocenters. This complex molecule is formed in Nature by cyclization of the acyclic, achiral farnesyl diphosphate in the presence of a
single enzyme called pentalenene synthase. Quantum chemical calculations on possible polycyclization pathways leading to pentalenene will be discussed. The structures of unusual and unexpected carbocation intermediates uncovered in these studies, such as the so-called "proton sandwiches" will be emphasized, and their implications for biochemical experiments on pentalenene synthase will be highlighted.

Professor Frieder Jaekle will present a seminar on Tuesday, April 25, 2006.

Talk Title: "Multifunctional Organoboranes: Lewis Acid Chemistry and Beyond"

Abstract: Among main group organic – inorganic hybrid polymers, those involving Group 14 and Group 15 elements have received tremendous attention over the past decades, with silicones, polysilanes, and polyphosphazenes among the most thoroughly studied polymeric materials. Polymers incorporating Group 13 elements are relatively less well established, despite potentially intriguing properties that may be derived from the electron-deficient nature of tricoordinate Group 13 species.

Several new methods that we have developed for the selective incorporation of Lewis acidic organoboron groups into the side chain and main chain of organic polymers will be discussed. The accessibility of the Lewis acid groups opens up new opportunities for applications, for example, in Lewis acid catalysis, chemical sensing, and the reversible assembly of polymers through donor-acceptor bonding.

Dr. Qiang Xu will present a seminar on Wednesday, April 26, 2006.

See Abstract below for further details.

Abstract:

Extensive efforts have been made to develop new hydrogen storage materials. Among these, 1) A high-performance hydrogen generation system based on transition metal-catalyzed dissociation and hydrolysis of ammonia-borane complex (NH₃BH₃) at room temperature has been achieved. This system can release hydrogen gas with an H₂ to NH₃BH₃ ratio up to 3.0, corresponding to 8.9 wt% of the starting materials NH3BH3 and H₂O with fast kinetics. 2) Sodium oxide, Na₂O, reversibly absorbs hydrogen, H₂, up to 3.0 wt% to form sodium hydride, NaH, and sodium hydroxide, NaOH, which possesses a potential to find its application to reversible hydrogen storage. A reaction intermediate, Na-H(delta-)...H(delta$B!G(B+)-ONa, involving dihydrogen bonding between the negatively charged hydrogen atom bonded to sodium and the positively charged hydrogen atom bonded to oxygen is proposed for the reaction mechanism. 3) Construction of new porous metal-organic frameworks with cubic building blocks, which may be promising for hydrogen storage.