The 8th Annual Northeast Student
Chemistry Research Conference
(NSCRC)
Saturday, April 22, 2006
Massachusetts Institute of Technology
The Ray and Maria Stata Center
Building 32
32 Vassar Street
Cambridge, MA
Book of Abstracts
Table of Contents
Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Members of the NSCRC 2006 Organizing Committee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
The American Chemical Society . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
The Northeastern Section of the American Chemical Society . . . . . . . . . . . . . . . . . . . . . . . . . 4
The American Chemical Society Division of Chemistry Education (CHED) . . . . . . . . . . . 5
Chemistry Education Committee Northeastern Section, American Chemical Society . . 5
American Chemical Society Younger Chemists Committee . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
The Northeastern Section Younger Chemists Committee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Schedule of Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Biography: The Keynote Speaker Professor Daniel G. Nocera of Massachusetts
Institute of Technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Oral Presentations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
Poster Presentations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Author Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
NSCRC 2006 2
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Members of the NSCRC 2006 Organizing Committee
Chair:Ivan Korendovych, Tufts University
Vice-Chairs:Alfio Fichera, MIT
William Neeley, MIT
WebMaster:Viatcheslav N. Azev, Tufts University
Program and Printing:Viatcheslav N. Azev, Tufts University
Laila Dafik, Tufts University
Gifts and Journal Committee:T. K. Subrahmanian, Tufts University
Laila Dafik, Tufts University
Arrangement and Promotion:Sapna Sharma, UMass-Dartmouth
LeAnn Williams, Shire
NSCRC 2006 3
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The American Chemical Society
The ACS is a self-governed individual membership organization
that consists of more than 163,000 members - 60 % from indus-
try, at all degree levels. This provides ample opportunity for
peer interaction, regardless of your professional or scientific inter-
ests.
The ACS seeks to:
� Promote the public perception and understanding of chemistry and the chemical
sciences through public outreach programs and public awareness campaigns
� Assist the federal government with advice on scientific and technological issues in-
volving the chemical sciences
� Enrich professionals in academia and private industry through development pro-
grams, peer interactions and continuing educational courses
� Host national, regional and local section meetings for the exchange of ideas, infor-
mation and chemical research discoveries
� Foster communication and understanding between members, the chemical industry,
the government and the community to enhance the quality of scientific research,
support economic progress and ensure public health and safety
The Northeastern Section of theAmerican Chemical Society
The chemical society of Philadelphia was the forerunner of what later
became the American Chemical Society. Celebrating 150 years the ACS
was founded in New York in 1896. Two years later in 1898, the North-
eastern Section of the ACS was begun when a group of 150 chemists
gathered together in Parker House, thus initiating a series of monthly
meetings which have continued to the present day. NESACS enjoyed
its centennial anniversary in 1998 and is one of the largest local sec-
tions. The current chair of NESACS is Patricia Mabrouk (Northeastern
University).
Membership activities have resulted in a number of National Awards, such as the
grassroots Award from the ACS office of Legislative and Government and the Outstanding
NSCRC 2006 4
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Local YCC Section Award. The NSYCC & the NSCRC are excellent examples of the way
in which a professional organization, working in tandem with its younger members, can
yield a fruitful outcome, ensuring continuing growth in membership and securing the
society’s future.
The American Chemical Society Division ofChemistry Education (CHED)
The American Chemical Society Devision of Chemical Education (CHED) is a mem-
bership division of the American Chemical Society. Its 6,000 members are teachers of
chemistry at pre-college, college, and university level, or are workers in indstry and gov-
erment with a particular interest in education.
CHED is governed by a fifteen-member Executive Committee. Thirteen of the mem-
bers are elected by the members of the Division; the other two are the Editor of the
Journal of Chemical Education and the Director of the ACS Examination Institute. The
work of the Division is carried out by many other committies and task forces.
Programming of the Division of Chemical Education is rich and varied, and member-
ship is open to anyone who is interested in furthering chemistry education. The major
vehicle for communication among CHED members is the Devision Newsletter and pro-
grams at national and regional meetings.
Chemistry Education Committee NortheasternSection, American Chemical Society
The Chemical Education Committee of the Northeastern Section of the American
Chemical Society sponsors programs to promote the interest and the involvement of stu-
dents and Educators in the chemical profession of the Society. The programmming is for
high school Teachers and their students as well as college and university students and
their Professors.
The prorgams for high school students and their Teachers include sponsorship of the
U. S. Chemistry Olimpiade Team, awards for outstanding teaching, National Chemistry
Week activities, and high school chemistry examination contests. Grants are also awarded
for regional meetings.
The undergraduates at all colleges and university are organized under the Student
Affiliates of the ACS. Summer Research Scholarships, travel grants for national ACS
meetings and regional prorgams are sponsored for them by the Committee. Regional
programs include an Undergraduate Day in celebration of National Chemistry Week an
the Northeast Chemistry Reserch Conference (NSCRC).
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American Chemical Society Younger ChemistsCommittee
The American Chemical Society Younger Chemists Committee was formed to identify
needs and concerns of younger chemists and to develop programs responsive to their needs.
We are driven by our three strategic goals:
1. To make the ACS relevant to younger chemists
2. Increase the involvement of younger chemists in the ACS at all levels
3. Develop mechanisms to integrate younger chemists into the profession
What are Younger Chemists? One YCC member coined the definition: ”Younger
chemists are people not yet established in their careers. The criterion for being a member
of this group is not age, but experience.”
YCC is a Joint Board-Council committee of the ACS whose members represent indus-
try, government and academies. Committee members are appointed for three-year terms
by the ACS President and Chairman of the Board. The Committee holds executive and
open sessions at each ACS national meeting and any interested chemist is welcome to
participate.
The Northeastern Section Younger ChemistsCommittee
The Northeastern Section Younger Chemists
Committee (NSYCC) is a local section YCC de-
voted to the professional advancement of chemists
in industry, government laboratories, undergrad-
uate institutions, graduate schools, and post-
doctoral positions. Its membership is drawn from
the northeast region’s colleges and universities,
corporations and laboratories. We hope to expand our membership in the NSYCC by
including representatives from different northeastern colleges and universities as well as
industrial corporations.
One of the most important annual events organized by the NSYCC is the Northeast
Student Chemistry Research Conference (NSCRC), now in its seventh year. This confer-
ence provides a forum for undergraduate and graduate students, as well as post-doctoral
fellows, to present research to their peers, exchange helpful ideas, practice presentation
skills, and network with other younger chemists from the Northeast.
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Another important program organized by the NSYCC is the German Exchange Pro-
gram. Each year since 2001, a group of younger chemists from either the Northeastern
Section of the ACS (NESACS) or the Gesellschaft Deutscher Chemiker (GDCh) has trav-
eled across the Atlantic Ocean to participate in this week-long program. The students are
selected based on applications, research accomplishments and recommendations. The pro-
gram usually consists of visits to local laboratories, tours of local companies, networking
events, and, of course, sight-seeing. In addition, the students are given the opportunity
to present their research in an international forum at a student research conference in
Boston, the NSCRC, and in Germany, the Euregionale.
Established in 1999, the NSYCC has been going strong ever since, gaining membership,
adding programs, and winning awards! The committee has won a ChemLuminary Award,
given by the ACS to recognize local section achievements.
The current Chair of NSYCC is Ivan Korendovych (Tufts University).
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Acknowledgements
The members of the Northeastern Section of the American Chemical Society’s Younger
Chemists Committee would like to thank the following people and sponsors for their
generous contributions:
Amanda Donathen, AAAS
Joseph Graham, ACS
Maureen Naff, Springer
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Schedule of Events
8:30 am - 9:00 am Poster Set-Up and Registration, Breakfast
9:00 am - 9:15 am Welcoming Remarks
9:15 am - 9:30 am German Exchange Presentation
9:30 am - 9:50 am D.R. Killelea (Tufts University) “Energy flow in gas-
surface reaction”.
9:50 am - 10:10 am Jessica C. DeMott (Brandeis University) “ Hyperco-
ordinate main group PNP pincer complexes”.
10:10 am - 10:30 am Laura B. Sessions (Dartmouth College) “Block
Copolymers for the Formation of Multimetallic
Nanocomposite and Nanoparticle Systems”.
10:30 am - 10:50 am Coffee Break
10:50 am - 11:10 am Ellen M. Sletten (Stonehill College) “A Flexible Stere-
ospecific Synthesis of Polyhydroxylated Pyrrolizidines
from Commercially Available Pyranosides”.
11:10 am - 11:30 am Andrea J. Gabert (MIT) “Synthesis and characteriza-
tion of ABA triblock copolymers with smectic C* liquid
crystal side chains via ring opening metathesis polymer-
ization using a bimetallic molybdenum initiator”.
11:30 am - 11:50 am Alisa A. Mueller (Harvard University) “Structure and
Mechanism of TadA, an Adenosine Deaminase That
Acts on tRNA”.
11:50 am - 12:30 pm Lunch
12:30 pm - 1:30 pm First Poster Session (odd numbered posters)
1:30 pm - 2:30 pm Second Poster Session (even numbered posters)
2:30 pm - 3:30 pm Keynote Address: Dr. Daniel G. Nocera of Massa-
chusetts Institute of Technology: “Powering the Planet:
The Challenge to Chemistry in the 21st Century”.
3:30 pm - 3:50 pm Awards Presentation
3:50 pm - 4:00 pm Closing Remarks, Poster Take-Down
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Dr. Daniel G. NoceraDepartment of Chemistry, Massachusetts Institute of Technology
Professor Daniel Nocera attended Rutgers University where he
received a B.S. in Chemistry, graduating with Highest Honors in
1979. He subsequently moved to the California Institute of Tech-
nology where he began research on electron transfer reactions in
biological and inorganic systems. After earning his Ph.D. degree in
1984, he accepted an appointment in the Chemistry Department
at Michigan State University where he was promoted to Professor
in 1990. In mid-summer 1997, he joined the Faculty of the Massa-
chusetts Institute of Technology where he is currently a Professor
of Chemistry.
He is W.M. Keck Professor of Energy at the Massachusetts Institute of Technology
and is widely recognized in the world as a leading researcher in energy at the molecular
level. He studied the basic mechanism of energy conversion in biology and chemistry
with primary focus in recent years in the photogeneration of hydrogen and oxygen and
pioneered each of these areas of science. He created the field of proton-coupled electron
transfer (PCET) at a mechanistic level with the publication of the first ultrafast laser
study of an electron transfer through a hydrogen bonded interface. His research group
focuses on the mechanisms of energy conversion in chemistry and biology. One of his
current projects focuses on the potential of solar energy schemes to produce alternative
fuels like hydrogen.
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Oral Presentations
1. Energy Flow in Gas-Surface Reactions
D.R. Killelea, A.L. Utz
Department of Chemistry, Tufts University, Medford, 62 Talbot Ave, MA, 02155
Energetic molecules play a key role in many chemical processes. Our experiments
probe the reactivity of energetic methane molecules impinging on a nickel surface and
reveal detailed insight into the dynamics of dissociative chemisorption. Some current
theories of CH4 dissociation on Ni surfaces assume rapid randomization of all energy in
the incident molecule. In this case, the reactivity would scale with total energy of the
incident CH4 molecule. Recent results from our lab show that the probability of CH4
dissociation on nickel surfaces is strongly dependent on the initial vibrational state of CH4.
In fact, the reaction is more effectively promoted with excitation of the antisymmetric
stretch in CH4 than translational energy or a bending mode that has 30% more energy.
These results are clear evidence of mode-specific chemistry. To explain these results, we
look at results that investigate the flow of vibrational energy from excited bonds and give
a time frame for the redistribution of energy. We conclude the mode specific behavior we
observe is the result of the internal energy of the CH4 molecules is staying localized, and
in fact it is the inability of the molecules to sample all the available states that leads to
non-statistical behavior.
2. Hypercoordinate Main Group PNP Pincer Complexes
Jessica C. DeMott, Chengyun Guo, Bruce M. Foxman and Oleg V.
Ozerov
Department of Chemistry, Brandeis University, MS 2308, 415 South Street, Waltham, MA02454
The focus of this work has been to investigate the use of PNP pincer ligands in the
formation of hypercoordinate main group element complexes. The family of PNP pincer
ligands has been used to stabilize unusual environments about metal centers through the
tridentate ligation of a central amido N-donor and two rigidly attached neutral phos-
phine arms. These ligands are also qualified to support hypercoordinate main group
complexes. Several approaches have been taken in the synthesis of the (PNP )AlCl2
and (PNP )AlR2. Characterization of these compounds, by methods including multinu-
clear NMR and X-ray crystallography, demonstrate hypercoordination at the Al center.
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Pentacoordinate systems of third period main group elements are not uncommon. The
formation of hypercoordinate second period complexes, however, is a far more appealing
challenge. Approaches to hypercoordinate boron complexes have been investigated and
multinuclear NMR support the formation of pentacoordinate systems.
3. Block Copolymers for the Formation of Multimetallic
Nanocomposite and Nanoparticle Systems
Laura B. Sessions, David S. Glueck, Robert B. Grubbs
Department of Chemistry, Dartmouth College 6128 Burke Labs Hanover, NH 03755
Polymers can function to assemble metallic species on the size-scale of the polymer,
leading to nanomaterials that have interesting properties due to their tiny dimensions. We
are interested in organizing two kinds of metallic nanocomposites within one multiblock
polymer system.
In the past, we have utilized diblock copolymers with one block containing pendant
alkyne groups for complexation with dicobalt octacarbonyl to form cobalt composite ma-
terials separated into block copolymer domains.[1] A second metallic species, gold, will
NSCRC 2006 12
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be added by use of a functional endgroup on the diblock copolymer (Figure 1). Thus far,
interesting magnetic properties have been found in these bimetallic systems due to the
cobalt-containing nanodomains.
[1] L. A. Miinea, L. B. Sessions, K. D. Ericson, D. S. Glueck, R. B. Grubbs, Macro-
molecules, 2004, 37, 8967.
4. A Flexible Stereospecific Synthesis of Polyhydroxylated
Pyrrolizidines from Commercially Available Pyranosides
Ellen M. Sletten, Louis J. Liotta
Department of Chemistry, Stonehill College, 320 Washington St. #1369 Easton, MA 02357
Nitrogen containing sugar analogs, known as azasugars or iminosugars, such as poly-
hydroxylated pyrrolidines, pyrrolizidines, and indolizidines, have the potential to become
important therapeutic agents due to their ability to inhibit glycosidases. Synthetic path-
ways that are able to systematically produce a variety of these azasugars are eagerly
sought after, since even minute structural or stereochemical changes often significantly al-
ter the degree of enzyme inhibition. The development of the synthesis of tetrahydroxylated
pyrrolizidines 3 and 4 starting from methyl-4,6-benzylidine- alpha,D-glucopyranoside, 1,
is described and will be used as a template to develop syntheses of all the stereoisomers
of 2,3,6,5 tetrahydroxylated pyrrolizidine as well as other analogous bicyclic polyhydrox-
ylated iminosugars.
The key steps in this synthesis involve a one-pot conversion of an iodopyranoside to a
divinyl amine by employing a simultaneous Zn reduction and reductive amination of the
resulting aldehyde. After protection of the amine, a ring closing metathesis results in a
multifunctional eight membered ring, which then undergoes an internal SN2 cyclization
to form an alkene-containing pyrrolizidine. Dihydroxylation of the alkene followed by
hydrogenolysis of the benzyl protecting groups results in tetrahydroxylated pyrrolizidines
3 and 4.
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5. Synthesis and Characterization of ABA Triblock Copolymers
With Smectic C* Liquid Crystal Side Chains via Ring Opening
Metathesis Polymerization Using a Bimetallic Molybdenum
Initiator
Andrea J. Gabert, Eric Verploegen, Paula T Hammond, and Richard R.
Schrock
Department of Chemistry, MIT, 77 Massachusetts Ave, Cambridge, MA 021239
A series of monomers suitable for ring opening metathesis polymerization (ROMP)
containing a side chain smectic C* liquid crystal mesogen (BPP4) have been synthe-
sized. Two of the monomers have BPP4 attached to norbornene with a six or ten carbon
spacer (NB6wBPP4 and NB10wBPP4, respectively), and the third monomer has BPP4
attached to norbornadiene via a ten carbon spacer (NBD10wBPP4). The monomers were
polymerized by ROMP using the bimetallic initiator, Mo(NAr)(OR)2[= CHC5H4]2Fe
(where Ar = 2,6-diisopropylphenyl, OR = CMe(CF3)2). ABA Triblock copolymers were
also synthesized where the A = NBD10wBPP4 or NBnwBPP4 (n = 6, 10) and B =
methyltetracyclododecene (MTD). All polymerizations were living and the polymers were
characterized by various techniques including polarized optical microscopy and differential
scanning calorimetry. The synthesis of the series of monomers, the synthesis of ABA tri-
block copolymers using the bimetallic molybdenum initiators, as well as characterization
of the resulting polymers will be presented.
6. Structure and Mechanism of TadA, an Adenosine Deaminase
That Acts on tRNA
Alisa A. Mueller, Heather C. Losey, Alexander J. Ruthenburg, and
Gregory L. Verdine
Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St.,Cambridge, MA 02138
The bacterial enzyme tRNA adenosine deaminase (TadA) enhances the versatility
of tRNA-Arginine-2 by converting an adenosine in its 5 wobble position to an inosine.
Although this protein is widely recognized for its crucial role in RNA editing, the precise
mode by which it recognizes and binds to its substrate to catalyze the reaction remains
elusive. We report two co-crystal structures. The first, of resolution 1.7 A, consists of
the E55Q mutant of TadA bound to a 16-mer tRNA minisubstrate representing the stem
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loop. This co-crystal structure models the structure of TadA prior to reaction with the
substrate. Crystal unit cells are composed of dimers of protein-RNA complexes with
RNA-RNA and protein-protein contacts governing the interactions between cells. The
second co-crystal structure, of resolution 2.4 A, represents the structure of TadA after
the reaction has been completed and consists of TadA E55Q bound to a 17-mer tRNA
minisubstrate.
We hope that our future research will verify that the position of the hydrated adenine
in its transition state is an intermediate between these two sites. Future endeavors are
directed towards obtaining crystal structures of TadA in its representative transition state.
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Poster Presentations
1. Investigation of Conformational Changes Upon Inhibition of
Diamine Oxidase
Sharon Aditya, Yuliya Allakhverdiyeva, Lear Brace, Michael Flaherty
Department of Chemistry, Emmanuel College, 400 The Fenway, Boston, MA 02115
Copper amine oxidases (CuAO) are ubiquitous enzymes that catalyze amine oxidation
to aldehydes and ammonia concomitant with the reduction of molecular oxygen to hydro-
gen peroxide. CuAOs contain both inorganic and organic cofactors. While the general
structure of the catalytic site is well known, a detailed understanding of the nature of
the interaction of the inhibitors and substrates with the organic cofactor is still to be
determined.
To further elucidate these effects, CuAO with substrates and inhibitors were submitted
to fluorimetric titrations. Energy Minimizations using MacroModel package (Schrodinger
Inc.) were performed on the same systems. Both computational and experimental results
have been applied to correlate the conformational changes in the enzyme upon binding of
substrates and inhibitors.
2. Nighttime Oxidation of VOCs at Appledore Island, ME
during ICARTT 2004
Ambrose, J. L., H. R. Mayne, J. Stutz, R. W. Talbot, and B. C. Sive
Chemsitry Department, University of New Hampshire, Durham, NH 03824
Ambient mixing ratios of trace gases important to nighttime chemistry of nitrate rad-
ical (NO3) were measured at Appledore Island (AI), ME, USA from July 2 - August
15, 2004 as part of the International Consortium for Atmospheric Research on Transport
and Transformation (ICARTT) campaign. These, together with the local meteorological
record and published kinetics data were used to investigate the nighttime oxidation of
volatile organic compounds (VOCs) at AI during the period July 9 - August 28. Addi-
tionally, ambient concentrations of dinitrogen pentoxide (N2O5) were estimated for the
nighttime hours from the measured concentrations of nitrogen dioxide (NO2) and NO3
and the corresponding equilibrium constant. The estimated N2O5 concentrations and cal-
culated water vapor concentrations were used to evaluate the importance of homogeneous
N2O5 hydrolysis to the overall nighttime removal of nitrogen oxides (NOx = NO + NO2)
relative to the gas-phase reactions of NO3 with VOCs. Furthermore, airflow patterns
were used to couple the trace gas measurements with source region influence.
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3. Synthesis and Application of Platinum-coated Polystyrene
Nanosphere Catalysts in Enantioselective Hydrogenations
Bela Torok, Ryan DeSousa, Kalyani Satuluri, Marianna Torok,
Valentina Atanassova, G. K.Surya Prakash
Department of Chemistry, University of Massachusetts Boston, 100 Morrissey Blvd., Boston,MA 02125-3393
Monodisperse polystyrene nanospheres have been prepared by emulsifier-free emulsion
polymerization with 4% crosslinking agent. The nanospheres have been produced in three
different sizes (250, 350 and 500 nm, respectively). The obtained nanospheres have been
coated with Platinum to obtain new hydrogenation catalysts. The Pt deposition on the
nanospheres have been carried out by several reduction methods. The catalysts have been
characterized by Scanning Elelctron Microscopy and Transmission Electron Microscopy to
determine the particle size and surface morphology of these systems. It was observed that
using the same reduction method, the nanospheres particle size had a significant effect on
the formation of the metal particles. The activity and selectivity of the synthesized cata-
lysts have been studied in the cinchona alkaloid modified enantioselective hydrogenation
of ethyl pyruvate. The test reaction revealed that the particle size of the nanospheres and
Pt particles had significant effect on the enantioselectivity of the hydrogenations. Under
optimized condition high optical yields have been obtained indicating the positive role of
the nonpolar polymer-support on modifier adsorption.
4. Mercury Uptake from Fish-Based Fertilizer by Spinach
Bonzagni, A., H. Magruder, and J. Benoit
Department of Chemistry, Wheaton College, Norton, MA 02766
This project investigates the potential for plant uptake of mercury from fish-based
fertilizer. These fish emulsions provide an organic alternative to chemical fertilizers, but
they may contain significant levels of mercury due to widespread environmental mercury
contamination and bioaccumulation in fish. We ascertained that Neptune’s Catch brand
fish fertilizer contains significant levels of methyl mercury, and we compared spinach
plants grown using this fish fertilizer with an inorganic nitrogen/phosphorus fertilizer
(Pete’s). Spinach plants were grown from seeds in Wheaton’s greenhouse, and half of the
plants were fed with Neptune’s Catch while the other plants were fed with Pete’s. Other
conditions (e.g. nitrogen additions, light levels) were matched for the treatments and the
controls. Both soils and leaves of the spinach plants were analyzed for total and methyl
mercury concentration.
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5. Templating the Growth Of Calcium Oxalate Monohydrate
On Gold via Microcontact Printing Of Self-assembled
Monolayers
Tania M. Cabrera, Leigh M. Friguglietti, Richard W. Gurney
Department of Chemistry, Simmons College, 300 The Fenway. Boston, MA 02115
Calcium oxalate monohydrate (COM) is the main inorganic component of kidney
stones. Crystal growth studies of COM would be greatly facilitated if nuclei seed crys-
tals were templated on surfaces, whereby, the size and nucleation density of the COM
seed could be controlled. The effect of impurities on the crystal growth of nucleated
COM crystals and the nucleation effect of the surface functional group can also be de-
termined directly by studying impurities in solution and different templates, respectively.
We adopted a route to crystal formation using micropatterned, self-assembled monolay-
ers (µP-SAM) of alkanethiols on Au. µ-squares of hydrophilic thiolates (−SC15H30CO2H,
−SC10H20CO2H, −SC11H22OH) were surrounded by a non-polar background
(−SC15H30CH3). The effects of chain length, hydrophilic w-group, and density of hy-
drophilic w-group per square were studied by modifying the µ-patterns, accordingly. The
effects of ion concentration and pH of buffered solution were studied by varying the COM
growth solution. Optimum incubation time for crystal growth was also considered. Re-
sults were documented using DIC microscopy. Future work will investigate the effect of
the size of and the spacing between the micron features.
6. Anion Binding to Monotopic and Ditopic Macrocyclic
Amides
Mimi Cho, Ivan V. Korendovych, Philip Butler, Richard J. Staples
and Elena V. Rybak-Akimova
Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, MA, 02155
Anion recognition by enzymes is of great interest, but the mechanisms of enzymatic
recognition of anions are still difficult to understand due to the complexity of biological
systems. The synthesis of small, biomimetic molecules capable of specifically binding an-
ions has been invaluable in examining the properties of substrate recognition. We have
synthesized 14, 15, and 30-membered macrocycles (1, 2, and 3 respectively), containing
amino groups and 2,6-diamidopyridine groups, which have well-established anion recog-
nition properties.
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The synthesized molecules were characterized spectroscopically and structurally by
X-ray diffraction methods. The binding properties of the macrocycles for various anions
were analyzed by 1H and 19F NMR. It was shown that at least a 15-membered ring is
required for binding F- anions. The large cavity size of 3 was found to accommodate two F-
anions. Macrocycle 3 was also discovered to bind larger anions such as monocarboxylates
and dicarboxylates, while the smaller macrocycles, 1 and 2, were not capable of binding
these anions. The data seem to support ditopic binding of the dicarboxylates.
7. Controlling Coiled Coil Stability Through Stereochemistry
Ginevra Clark and Krishna Kumar
Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, MA, 02155
This project utilizes (2S, 3S) and (2S, 3R) trifluorovaline (TFV), and (2S, 4S) and
(2S, 4R) trifluoroleucine (TFL) to study the effects of stereochemistry on the packing
of core residues in a coiled coil motif. A coiled coil composed of TFV and TFL will
contain a spatially constrained array of CH3 and CF3 groups. We want to determine
what stereochemical features are relevant to peptide folding, and how the properties of
the CF3 group perturb these preferences.
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One can anticipate that the trifluoroleucine and trifluorovaline diastereomers will have
similar chemical properties, but quite different packing preferences. Two peptides, SS and
RR were synthesized. SS was designed with (2S, 3S) trifluorovaline at “a” positions and
(2S, 4S) trifluoroleucine at “d” positions in a coiled coil motif. RR is composed of (2S, 3R)
trifluorovaline and (2S, 4R) trifluoroleucine at the corresponding positions. Preliminary
studies suggest that a disulfide-bonded dimer of RR (RR-RR) is more stable than the
dimer of SS (SS-SS). AUC data suggests that while RR-RR appears to form a stable
disulfide-bonded dimer, SS-SS is present in multiple oligomerization states. Furthermore,
disulfide exchange experiments reveal a strong preference for the heterodimer (RR-SS).
8. Cucurbit[7]uril As a Molecular Platform For the Association
And Isolation Of Monosaccharides
Bethany C. Collins and Steven C. Haefner
Department of Chemical Sciences, Bridgewater State College, Bridgewater, MA 02325
Cucurbit[7]uril (CB[7]) was synthesized according to a standard literature procedure
and separated from all other homologues by selective dissolution and recrystallization.
While CB[7] is insoluble in water, addition of monosaccharides results in a marked in-
crease in solubility. The interactions between CB[7] and aqueous monosaccharides were
studied using various techniques including infrared and NMR spectroscopies. Prelimi-
nary results indicate that glucose solutions preferentially interact with CB[7] relative to
other homologues, and we have found that CB[7] and monosaccharides associate to form a
hydrogen-bonded complex which can be isolated from solution by the use of a precipitating
solvent, namely acetone or acetonitrile. Interactions between CB[7] and monosaccharides
produce a significant upfield shift of the CB[7] protons as evidenced by 1H NMR. The
synthesis, isolation, and characterization of CB[7] and its subsequent interactions with
glucose and mannose will be presented.
9. Fluorination of Cell Surfaces Using Biosynthesis
Laila Dafik, Marc d’Alarcao, Krishna Kumar
Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, MA, 02155
The cell surface is the province of diverse oligosaccharide structures that participate
in a wide spectrum of biological recognition events. Metabolic engineering allows the
incorporation of unnatural glycans on cell surfaces, and therefore the modification of its
properties. The sialic acid biosynthetic pathway allows for such alteration - its toler-
ance has been demonstrated towards multiple unnatural substrates, such as derivatives
NSCRC 2006 20
Book of Abstracts
of Nacyl mannosamine and sialic acid. We have demonstrated the incorporation of flu-
orinated groups on mammalian cell surfaces using this pathway. The incorporation of
unnatural, exogenously supplied mannosamine and/or sialic acid derivatives could lead
to the generation of non-stick mammalian cells and also exhibit phenotypic properties
that are anti-metastatic providing leads in the development of new drug candidates. We
have tested multiple fluorinated substrates and catalogued their incorporation on mam-
malian cell surface proteins and/or lipids. Cell suspensions (HL-60, Jurkat and HeLa)
were incubated with the synthetic compounds and cell membrane fractions were col-
lected after 72 hours. The sialic acid fraction membrane-bounded glycoproteins -were
hydrolyzed and subsequently analyzed after derivatization with the fluorescent agent 1,2-
diamino-4,5-dimethylenedioxybenzene (DMB). The DMB labeled sialic acids could then
be quantitated.
10. AlkB Reverses Etheno DNA Lesions Caused by Lipid
Oxidation in itro and in vivo
J.Delaney, L.Smeester, C.Wong, L.Frick, K.Taghizadeh, J.Wishnok,
C.Drennan, L.Samson and J.Essigmann
Department of Chemistry, MIT, 77 Massachusetts Ave, Cambridge, MA 021239
Oxidative stress converts lipids into DNA damaging agents. The genomic lesions
formed include 1,N6-ethenoadenine (eA) and 3,N4-ethenocytosine (eC), in which two
carbons of the lipid alkyl chain form an exocyclic adduct with a DNA base. We have
built viral genomes containing these lesions, which were passed through E. coli containing
or lacking the recently characterized DNA repair enzyme AlkB, which has been thought
to repair only 1-alkylpurines and 3-alkylpyrimidines by a direct reversal of base damage
mechanism. We have developed genetic assays revealing eA to be very toxic and mutagenic
in an AlkB-deficient cell; however, both toxicity and mutagenicity were eliminated in E.
coli containing AlkB, thereby implicating a new substrate which AlkB can repair by an
unprecedented direct reversal mechanism. ESI-TOF mass spectrometry performed on a
16mer containing eA reacted with purified AlkB revealed intermediates along the AlkB
repair pathway, consistent with eA being epoxidized by AlkB, followed by hydrolysis of the
epoxide to form the eA-glycol prior to dealkylation to restore the undamaged adenine base.
Gas chromatography mass spectrometry revealed the jettisoned alkyl group is released as
the dialdehyde, glyoxal.
NSCRC 2006 21
Book of Abstracts
11. Synthesis of Indole and Oxindole Derivatives Of
Glutathione As Potential Inhibitors Of Glyoxalase II
Alison Erbeck and Edward Brush
Department of Chemical Sciences, Bridgewater State College, Bridgewater, MA 02325
The glyoxalase system performs key roles in biological detoxification and cell growth.
The system is made up of two enzymes, glyoxalase I (GxI) and glyoxalase II (GxII),
which use glutathione as a co-substrate. These enzymes are involved in a variety of
diseases, and are considered to be therapeutic targets. My work has focused on the syn-
thesis of unique indole and oxindole conjugates with glutathione as potential reversible
or irreversible inhibitors for GxII. The following compounds were synthesized: ethyl 3-
bromooxindole acetic acid, 3-methyleneoxindole, S-glutathionyl-3-bromooxindole acetate,
S-glutathionyl-3-indole acetic acid, and S-glutathionyl-3-methyleneoxindole, and charac-
terized using NMR, HPLC, and UV-Vis spectroscopy. Preliminary kinetic analysis indi-
cates that these compounds are good inhibitors of GxII, with greater than 50% inhibition
by 1 mM ethyl 3-bromooxindole acetic acid and 3-methyleneoxindole. This research may
contribute to further defining the role that GxII plays in human disease. This research
was supported by a Norris/Richards Scholarship and the Adrian Tinsley Program.
12. Scope and Mechanism Of a New Aromatic
ortho-Hydroxylation With Hydrogen Peroxide And Biomimetic
Iron Complexes.
Margaret M. Flook, Sonia Taktak, Elena V. Rybak-Akimova
Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, MA, 02155
The non-heme iron(II) complex of BPMEN (BPMEN = N,N’- dimethyl- N,N’- bis(2-
pyridylmethyl)ethane- 1,2- diamine) mimics the active site iron-containing enzymes, and
was recently found to efficiently promote ortho-hydroxylation of benzoic acids using hydro-
gen peroxide as the oxidant. Previously in this project, the focus has been on determining
the scope of this reaction. The effect of position and nature of substituents (methyl, nitro,
chloro) had been investigated using UV-Vis, ESI-MS and NMR techniques. A continua-
tion of this work is presented here, including a broader range of substituents and more
complete NMR and UV-Vis data, to further describe the scope of this complex in pro-
moting selective aromatic hydroxylations. Along with these studies, a new large-scale
extraction of the salicylic acid product was performed. Also, the results of recent kinetic
NSCRC 2006 22
Book of Abstracts
studies are to be presented here, which will help shed light on the mechanism of the
oxidation reaction.
13. Catalytic and Stoichiometric Reactions Of Nickel and
Palladium Pincer Complexes
Oleg V. Ozerov, Lauren C. Gregor, Lei Fan
Department of Chemistry, Brandeis University, MS 2308, 415 South Street, Waltham, MA02454
Pincer ligands can be used to form metal complexes which are extraordinary tools
used in the exploration of organometallic chemistry. Their high stability, reactivity, and
selectivity make them excellent candidates as catalysts for many organic reactions. The
rigid diarylamido-based PNP pincer ligands utilized here have been shown to yield unusual
structures and catalytic reactivity with a variety of metal centers. In general, nickel is
an underused metal in pincer ligand chemistry and it has been our goal to investigate
reactions of a variety of nickel pincer complexes utilizing the different PNP ligands. The
(PNP)NiOTf complex (OTf = trifluoromethanesulfonate) serves as a synthon for the
(PNP )Ni+ cation because of the ease in which the triflate ion can be displaced and
can act as a practical Lewis acid for catalysis reactions. The (PNP)NiOTf complex is
an efficient catalyst for the coupling of aldehydes with acetonitrile, which prompted the
exploration of other aldehyde coupling reactions. Attempts to couple aldehydes with
alkynes led to unusual results in which various Ni-alkynyl and Ni-alkyne complexes were
formed. Difficulty in isolating the products led to the switch to (PNP)Pd complexes in
order to investigate the alkyne reactions.
NSCRC 2006 23
Book of Abstracts
14. Rechargable Organic Dye Cells
F.A.Horan S.K.Swope, A.B.Waghe
Chemical, Earth, Atmospheric and Physical Sciences Department, Plymouth State University,MSC 48,Plymouth, NH 03264
Organic dyes have found various nontraditional applications in recording, displays and
medical and pharmaceutical use. However, we have found that many of these dyes can
store electrical charge. The test results from six dyes indicate methyl green dye (1%
solution) when charged with 2 volt DC, stores charge for 10 minutes in water. The dye
separates into oxidized and reduced forms when electric potential is applied. These forms
lose or gain electrons to get back to their original states, resulting into current through an
external circuit. The bulkier ions do not diffuse rapidly which helps dyes to store charges
when they are charged. Charging and discharging curves of various dyes and different pH
and conditions are presented here. Half cells of a dye in acidic solution when connected
to half cell of same dye in a basic solution also showed electrical output indicating the
reduced and oxidized form of dyes are generating this current. This work may lead to
novel electric storage device
15. Synthesis of Vinyl and Polyhydroxylated Pyrrolidines and
Subsequent Purification Attempts using High Performance
Liquid Chromatography
James T. Hummel and Louis J. Liotta
Department od Chemistry, Stonehill College, 320 Washington Street, Easton, MA 02357
The synthesis of polyhydroxylated pyrrolidines is of substantial interest because of
the ability of these compounds to inhibit glycosidases, a group of carbohydrate process-
ing enzymes. Such inhibition results in the activity of polyhydroxylated pyrrolidines
as antiviral and antitumor agents. Purification of such compounds is a crucial step to
fully understanding how these compounds interact with the active site of glycosidases.
Through a series of reactions outlined in Scheme 1 the intermediate vinyl pyrrolidine 6
has been synthesized in a 23 % yield. Further reacting intermediate 6 with catalytic
osmium tetroxide in N-methylmorphiline-N-oxide allowed for the successful synthesis of
dihydroxylated, dibenzyl pyrrolidines 18a and 18b in a reasonable yield of 16 %. Ini-
tial separation attempts of diols 18a and 18b were conducted using C18 reverse phase
chromatography, which was inconclusive. Further attempts to separate diols 18a and 18b
should be investigated with an amino-containing normal-phase column.
NSCRC 2006 24
Book of Abstracts
16. Aminosilane [4+2] Annulations Toward the Synthesis of
Alkaloid (-)-205B
Leland L. Johnson, Jr., James S. Panek
Department of Chemistry, Boston University, 590 Commonwealth Avenue, Boston, MA 02215
Hundreds of alkaloids containing quinolizidine and indolizidine core structures have
been isolated, and many have been found to possess potent biological activity. [1] These
compounds have proven to be synthetically challenging targets, due to their complex
core structures. The Panek chiral aminosilane technology began with Sparks in the early
90s[2], and has led to the application of these emerging methodologies toward the syn-
thesis of numerous natural product and natural product-like fragments and molecules.[3]
Recently, Huang and Panek have published the total synthesis of alkaloid (-)-217A uti-
lizing aminosilanes in a [4+2] annulation strategy.[4] Expanding the aminosilane [4+2]
annulation methodology, we have embarked on several projects to further develop this
methodology, including the progress toward the enantioselective synthesis of the tricyclic,
aza-acenaphthalene alkaloid (-)-205B.[5]
The retrosynthetic analysis, and corresponding forward synthesis of alkaloid (-)-205B,
as well as additional isomers, will be reviewed. New methods incorporating fully - sub-
stituted stereocenters and adjacent, fully - substituted stereocenters[6] into our repertoire
will also be discussed.
17. The Preparation of Novel Fluorescent Sensors for Divalent
Zinc
Daniel P. Kennedy, Arnold L. Rheingold, Roy P. Planalp
Department of Chemistry, University of New Hampshire, 23 College Rd, Durham, NH 03824
NSCRC 2006 25
Book of Abstracts
A variety of novel N-heterocyclic containing ligands based on the TAME framework
(TAME=1,1,1-tris(aminomethyl)ethane) have been prepared for the fluorescence detec-
tion of divalent zinc. The complex [Zn(TAMEisoquin)]2+ (Fig.1) demonstrates a 14 fold
enhancement of the emission intensity as compared to that of the free ligand. Solutions
of TAMEisoquin with the metals Na+, K+,Mg2+, Ca2+,Mn2+, Fe2+, Co2+, Ni2+, Cu2+,
and Cd2+ (1:1 DMF:water at RT) did not show significant enhancement of the emis-
sion intensity as compared to the free ligand. The known fluorescent zinc sensor TQEN
(TQEN=2-quinolinylmethyl)ethylenediamine) was shown by Mikata and coworkers to
possess a 23 fold enhancement of emission intensity in the presence of Zn2+, but this
ligand also showed a 14 fold enhancement in the presence of Cd2+.[1] The complex
[Cd(TAMEisoquin)]2+ undergoes rapid racemization at room temperature because of
the poor match between the size of the cation and the binding cavity of the ligand, thus
attenuating the emission intensity. Synthesis of the ligands, crystal structures of their
complexes, and their potential as new fluorescent sensors for zinc will be discussed.
[1] Mikata, Y.; Wakamatsu, M.; Yano, S. Dalton Trans., 2005, 545-550.
18. Diiron(II) µ−aqua µ−hydroxo Model for Non-Heme Iron
Sites in Proteins
Ivan V. Korendovych, Sergey V. Kryatov, William M. Reiff,
Elena V. Rybak Akimova
Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, MA, 02155
We have synthesized a diiron(II) complex with a novel aqua-hydroxo bridging motif,
[Fe2(µ−H2O)(µ−OH)(TPA)2](OTf)3 (1). This is a new member of the diiron diamond
core family. The complex is stable in solution in non-polar solvents as well as in the solid
NSCRC 2006 26
Book of Abstracts
state; two hydroxides are not required to keep diiron core intact. Replacing of one of the
two hydroxo bridges with H2O bridge does not disrupt electronic communication between
two Fe(II) sites.
The drastic difference of ca. 1 V in redox potential between complex 1 and its bis-
hydroxo bridged analog Fe2(OH)2(TPA)3+ is accompanied by only moderate difference
in dioxygen reactivity. This observation is consistent with the inner-sphere mechanism of
iron(II)-dioxygen association rather than the outer-sphere electron transfer. Oxygenation
of 1 in dichloromethane at low temperature in the presence of CoCp2 results in formation
of new intermediate. Investigation of the nature of this intermediate is in progress. One-
electron oxidation of 1 produces mixed-valent diiron(II)-bis-µ−hydroxo TPA complex.
19. Synthesis of Benzo[N,X] Heterocycles (X=N, O) by
Microwave Assisted Solvent-Free Solid Acid Catalyzed
Cyclizations
Shainaz M. Landge, Bela Torok
Department of Chemistry, University of Massachusetts Boston, 100 Morrissey Blvd., Boston,MA 02125-3393
The synthesis of several types of benzo[N,X]-heterocycles, such benzimidazoles, ben-
zodiazepines, benzoxazepines by a solvent-free solid acid catalyzed method is described.
The commercially available and inexpensive K-10 montmorillonite is an excellent catalyst
for the synthesis of the target compounds. The reactions have been carried out using
NH2
NH2
R
R1 CHO
R3
O
K-10, mwR
N
NR1
R
R1
N
N
R3
R3
R2R2
R2
NH2
OH
R R3
O
K-10, mw
R2
R
O
N
R3
R3
R2
R2R = H, 4-Cl, 3-Me, 4-MeR1 = H, Me, 2-pentyl, Ph, 1-cyclohexenylR2 = H, MeR3 = Me, Et, iPr
Scheme 1 Synthesis of benzimidazoles, benzodiazepines and benzoxazepines with microwave assisted K-10 montmorillonite catalyzed cyclization of o-phenyle nediamines and o-aminophenols with ketones and aldehydes
K-10, mw
a wide variety of o-functionlized aniline derivatives (NH2 and OH), along with ketones,
NSCRC 2006 27
Book of Abstracts
aldehydes and some bifunctional reagents such as ketoesters and diketones. The cycliza-
tion reactions have been initiated by microwave irradiation and provided the products
in very high yields (up to 98%) and excellent selectivities in very short reaction times
(1-14min). The effective combination of solid acid catalysis, solvent-free conditions and
microwave irradiation provides an attractive highly ecofriendly approach for the synthesis
of these important heterocycles. Beyond these, the ease of product isolation, catalyst sta-
bility and handling make this process an attractive, environmentally benign alternative
for the synthesis of the target compounds.
20. Synthesis Of Solvated Rh(III) Bis-bipyridine Complexes and
Their Subsequent Reactivity With D-glucose and D-mannose
Sarah M. Lane, Steven C. Haefner
Department of Chemical Sciences, Bridgewater State College, Bridgewater, MA 02325
Our group is currently examining the ability of transition metal complexes to se-
lectively bind with specific monosaccharides such as D-glucose and D-mannose. Initial
efforts have focused on the synthesis and subsequent reactivity of Rh(III) bis-bipyridine
complexes. These complexes have accessible cis-coordination sites stabilized by solvents
such as DMF or acetonitrile. Reaction of cis − [Rh(bpy)2Cl2]+ with two equivalents of
AgBF4 does not give the expected disubstituted species, [Rh(bpy)2(DMF )2]3+. Instead,
the monosubstituted complex, [Rh(bpy)2(DMF )Cl]2+ was obtained in 34% yield. The 1H
NMR studies of [Rh(bpy)2(DMF )Cl]2+ confirmed the adjacent position of the DMF and
Cl− groups. Likewise, reaction of [Rh(bpy)2(Cl)2]+ with neat triflic acid produces cis and
trans isomers of [Rh(bpy)2(OTf)Cl]+ instead of the expected bis-triflate complex. Titra-
tion studies indicate that both cis − [Rh(bpy)2(DMF )Cl]2+ and [Rh(bpy)2(OTf)Cl]+
react with glucose in basic solutions. The synthesis and characterization of these Rh(III)
complexes, as well as their reactions with simple monosaccharides will be presented.
21. Single Crystalline Ice Growth And Evaluation
Irene Li, Henning Groenzin, Mary Jane Shultz
Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, MA, 02155
Although water (and its solid form, ice) is among the most abundant substances on
earth, its chemical and physical properties are surprisingly little investigated. The reason
for this lack of understanding lies in the intrinsic difficulties of investigating ice. Ice tends
to grow dendritically (a form of mathematical chaos), making sample preparations of a
consistent and repeatable nature challenging.
NSCRC 2006 28
Book of Abstracts
We grow cylindrical ice pieces of 1” diameter and 4” length with single crystalline
domains in the range of 20-25 cm3. Samples are grown on a vibration isolation table
under highly controlled conditions which include growth rate, bath temperature, convec-
tion minimization, and water equilibration time. Crossed polarizers are used to evaluate
crystalline domain size, as well as to determine the c-axis orientation via a custom-made
Rigsby stage comprised of four independently rotatable axis situated between two crossed
polarizers. Further verification is done through selective etching with a Formvar solution;
there are characteristic etchpit shapes unique to each orientation. It was found that the
c-axis is oriented approximately perpendicular to the ice growth direction.
The ice is used for further studies by sum-frequency generation (SFG) a nonlinear
optical technique uniquely suited for surface studies.
22. Refractive Index and the Non-ideality of Pyridine
Leanne Lortie, Herbert Ellison
Department of Chemistry, Wheaton College, W0919 26 E. Main Street, Norton MA 02766
This work was designed to further establish the nonideality of pyridine in solution by
examining changes in refractive index. Several series of solutions were prepared using
cyclohexane as a solvent, ranging in concentration from 0.1 to 1.4M, and the refractive
index of each solution was measured using a thermostated refractometer set to 25C.
Analyzing the trend in the refractive index of the solutions versus either the molarity or
mole fraction of pyridine, leads to the conclusion that a polynomial function fits the data
better than a linear function. An ideal solution shows a linear dependence of refractive
index on concentration. This was confirmed after analyzing the refractive index versus
the molarity or mole fraction of ideal solutions of toluene, o-xylene and acetophenone,
which gave linear functions as lines of best fit. The pyridine data strongly suggests that
this solute forms a dimer in solution, although to only a slight extent.
23. Synthesis and Reactivity of Solvated Ru(II/III) Chelates
With Monosaccharides
Lindsay T. McDonald and Steven C. Haefner
Department of Chemical Sciences, Bridgewater State College, Bridgewater, MA 02325
Metal-saccharide interactions are widely observed in biological systems. Despite this,
only a limited number of well-characterized metal-saccharide species have been reported,
especially amongst the 2nd and 3rd row transition metals. In an effort to expand this
NSCRC 2006 29
Book of Abstracts
field, and as an initial step towards the development of metal based artificial recep-
tors, we are currently examining the reactivity of cis − [Ru(bpy)2(DMF )2][BF4]2 (1),
cis − [Ru(acac)2(CH3CN)2][BF4] (2), and cis − [Ru(bpy)2(MeOH)2][BF4]2 (3) with
monosaccharides such as glucose, mannose and glucosamine. The previously unreported
complex 1 was synthesized from cis − Ru(bpy)2Cl2 in 80% yield by halide abstraction
with AgBF4. The cis-arrangement of the DMF ligands was confirmed by 1H NMR spec-
troscopy. Saccharide binding studies with 1 and 2 produced essentially no changes in
the UV-visible spectrum. However complex 3 exhibited an increase in Uv-visible ab-
sorbance with increasing saccharide concentration indicative of metal-saccharide complex-
ation. This result suggests that saccharide binding is possible in the presence of weakly
donating, monodentate solvents such as methanol. In an effort to strengthen the metal-
saccharide interactions, the reactivity of (1) with glucosamine was also examined. NMR
spectroscopic studies indicate formation of a new ruthenium species and are suggestive of
a chelating interaction with glucosamine.
24. Probing Fluorination Effects On Model Antimicrobial
Peptides
He Meng and Krishna Kumar
Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, MA, 02155
We demonstrate that antimicrobial activity and proteolytic stability of antimicrobial
peptides can be improved to some extent by incorporation of hexafluoroleucine. Sec-
ondary structure formation and aggregation of monomer were enhanced upon fluorina-
tion. Hemolytic activity was elevated in M2 series and has not shown apparent change
for BII series. These results implicate that fluorination may be applicable to engineer
potentially therapeutic peptides.
25. Highly Asymmetric Heterogeneous Catalytic Hydrogenation
of Isophorone on Proline Modified Palladium Catalysts
Shilpa C. Mhadgut, Marianna Torok, Joseph Esquibel and Bela Torok
Department of Chemistry, University of Massachusetts Boston, 100 Morrissey Blvd., Boston,MA 02125-3393
Special importance of chiral molecules in numerous domain of our life provides ex-
traordinary potential for asymmetric synthesis. Heterogeneous asymmetric catalytic hy-
drogenation is one of the most versatile methods in synthesis of chiral compounds. The
NSCRC 2006 30
Book of Abstracts
development of a highly enantioselective heterogeneous hydrogenation catalyst, based on
proline modified Pd catalysts is described. It was first used in the sonochemical asymmet-
ric hydrogenation of isophorone (3,3,5-trimethyl-2-cyclohexenone). The process resulted
in highly enhanced enantioselectivities up to 85% enantiomeric excess (ee). The key fac-
tor in achieving high ee in this system was adsorption of proline on the catalyst surface.
The catalyst/proline mixture was presonicated with ultrasounds and then hydrogenation
was performed. The results initiated the idea of improving catalyst-modifier interaction
through ionic (acid-base) interaction. When several base-supported Pd catalysts such as
Pd/BaCO3, Pd/CaCO3 and Pd/SrCO3 were used, the expected effect was outstanding.
It was observed that the (S)- and (R)-proline provided the opposite enantiomers of the
product with nearly the same ee values (99 and 97% ee respectively). Effective combi-
nation of enhanced proline adsorption and secondary kinetic resolution resulted in the
excellent enantioselectivities.
26. Design, Synthesis, and Testing of Indole and Oxindole
Aspartic Acid Derivatives as Potential Caspase Inhibitors
David Mofford and Edward Brush
Department of Chemical Sciences, Bridgewater State College, Bridgewater, MA 02325
Multicellular organisms dispose of damaged cells through apoptosis, initiated by ac-
tivating a family of enzymes called caspases. However, unregulated caspase activation
results in the death of healthy cells, contributing to neurodegenerative disease. Caspase
inhibition is thought to be a promising direction in the treatment of these diseases. Our
goal is to synthesize N-aspartyl amide derivatives of indole and oxindole acetic acids,
and evaluate these compounds as potential caspase inhibitors. Our preliminary inhibi-
tion data are promising, with 3-methyleneoxindole (69%), indole-3-acetic acid (29%), and
N-aspartylindole-3-acetate (44%) all producing modest inhibition of caspase-3. Current
efforts are focused on the synthesis and characterization of the potential mechanism-based
inhibitors N-aspartyloxindole-3-acetate and N-aspartyl-3-bromooxindole-3-acetate. This
research may lead to new information about caspase and apoptosis inhibition and ulti-
mately to the development of new therapeutic agents. This work was made possible by
a grant from the Adrian Tinsley Program for Undergraduate Research at Bridgewater
State College.
NSCRC 2006 31
Book of Abstracts
27. A New Class of Organofluorine Inhibitors of Amyloid
Fibrillogenesis: Synthesis And In Vitro QSAR Studies
Mohammed Abid, Shilpa Mhadgut, Marianna Torok, Bela Torok
Department of Chemistry, University of Massachusetts Boston, 100 Morrissey Blvd., Boston,MA 02125-3393
Synthesis of novel trifluoromethylated indole derivatives and their application as ef-
fective inhibitors of amyloid fibrillogenesis is described. These inhibitors were synthesized
by solid acid-catalyzed Friedel-Crafts hydroxyalkylation of indoles and pyrroles with ethyl
3,3,3 trifluoropyruvate and ethyl 4,4,4 trifluoroacetoacetate. The inexpensive and read-
ily available K-10 montmorillonite was found to be an efficient catalyst for this synthesis.
The products were isolated in excellent yield and selectivity under mild experimental con-
ditions, during very short reaction times. Use of naturally occurring clay catalyst makes
this process environmentally benign.
The above synthesized products were tested as inhibitors of amyloid fibrillogenesis.
All substituted indole derivatives have shown considerable effect (20-70% inhibition) in
structure-activity relationship studies, some of them demonstrated excellent activity (93-
96% inhibition). Further studies showed that each functional group from the core structure
has significant role. The elimination of any of these functional groups resulted in a partial
or complete loss of activity.
NSCRC 2006 32
Book of Abstracts
28. Study of Titanium Catalyzed Enyne Hydroaminations
Taryn D. Palluccio, Stephen A. Waratuke
Department of Chemical Sciences, Bridgewater State College, Bridgewater, MA 02325
Hydroamination reactions involve the addition of an amine to an alkene or alkyne and
are typically performed in the presence of a catalyst. The steric and electronic nature
of the catalyst can control the regio- and stereo-selective formation of hydroamination
products as well as provide an efficient reaction pathway. As the alkene and alkyne
functional groups are known to have different activities toward hydroamination, my ini-
tial catalytic studies have focused on alkyne and enyne hydroaminations with activated
amines using titanium aryloxide catalysts. One of our goals upon optimization of the
reaction methodology is to explore diene hydroamination reactions which are challenging
for most transition metal catalysts. The syntheses of starting materials and catalytic hy-
droamination reactions are conducted using Schlenk lines, a dry box, and other moisture
sensitive techniques. All reactions are monitored by GC/MS and NMR spectroscopy. Our
preliminary results will be presented as well as a general overview of the project.
29. Study Of Ligands
Jared Pearl and Stephen Waratuke
Department of Chemical Sciences, Bridgewater State College, Bridgewater, MA 02325
My project is the synthesis of bulky ligands with nitrogen and oxygen binding sites to
serve as ligands to group 4 metal centers. The two ligand classes that I have begun working
on are tripodal amine ligands and substituted phenoxides. The tripodal amine model
compounds are [tris(2-pyridylmethyl)amine] or TPA, and [tris(2 benzimidazoylmethyl)
amine] or NTB. The synthesis method, purification, and spectroscopic data for these
amines have been reported in the literature. The synthesis of 2,3,5,6-tetraphenyl phenol
serves as the model for the second class of molecules. Understanding the ability of these
ligands to donate electrons and alter the electronics of the metal center while also altering
the geometry at the potential binding sites is crucial to the development of ligands for
catalysis. A great deal of interest in using these types of ligands to support catalytic
carbon-carbon and carbon-nitrogen bond formation is evident in the literature. The
synthesis, methodology, and current new ligand targets will be presented as well as the
overall goals of the project.
NSCRC 2006 33
Book of Abstracts
30. Conducting Organic Polymer Networks Of
Poly(Norbornylene) Containing Bis-EDOT Monomers Via
Solid-State Oxidative Conversion
Mustafa S. Yavuz, Samuel A. Pendergraph,Gregory A. Sotzing
Department of Chemistry, University of Connecticut, 97 N. Eagleville Rd. Storrs, CT 06269
Herein, we describe the preparation of conducting polymers containing
3,4-ethylenedioxythiophene (EDOT) moieties via two different routes: solution, and solid-
state oxidative conversion (SOC) into the respective conjugated polymer. The impact of
our SOC technique over the conventional solution system include: high yields, processabil-
ity, and lower costs. The processable poly(norbornylene) precursors containing oxidatively
polymerizable BisEDOT-Benzene and BisEDOT-Thiophene units have been synthesized.
Conducting polymers obtained via the conventional electro-deposition were compared to
polymers obtained via SOC and were found to have similar behavior. Furthermore, we
have demonstrated that the conversion to conductive polymer in the solid state can be
obtained not only via electrochemical oxidation, but also via chemical oxidation using
ferric chloride.
31. Relationship Between Collagen Structural Hierarchy and
Susceptibility to Degradation by Ultraviolet Radiation
Olena Rabotyagova, Peggy Ceby, David Kaplan
BME/Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, MA, 02155
Collagen type I is the most abundant extracellular matrix protein in the human body,
providing the basis for tissue structure and directing cellular functions. In the present
study, we examined the relationship between collagen structure (native vs. denatured)
and sensitivity to UV radiation (λ = 254 nm, I= 7.3x10−3Watt/cm2). Structure and
functional changes in the collagens in film form were related to the initial conforma-
tion (native vs. denatured) and energy of irradiation exposure. These changes were
tracked using SDS-PAGE to assess molecular weight, Fourier transform infrared (FTIR)
spectroscopy to study changes in the secondary structure, and atomic force microscopy
(AFM) to characterize changes in mechanical properties of the films. Differences were
found at the molecular (primary structure), nano and mesoscopic (conformation and su-
percoiling of the triple helices) and macro levels with differences in mechanical properties.
In general, susceptibility to the effects of radiation was higher for collagen in the native
conformation. The results suggest that the negative effects of electromagnetic radiation
NSCRC 2006 34
Book of Abstracts
on extracellular matrices are important to assess in the context of the state of collagen
structure with implications in tissue remodeling, wound repair and disease progression.
32.
Maolin Guo, Elise Rapoza, Yibin Wei, Gregory Su
Department of Chemistry and Biochemistry, University of Massachusetts Dartmouth, 285 OldWestport Rd, Dartmouth, MA, 02747
The North American native fruit cranberry (Vaccinium macrocarpon, Ait. Ericaceae)
have long been known to contain compounds with beneficial health effects (against infec-
tions, cancer, aging, stroke and cardiovascular diseases). However, little is known about
the biochemical mechanism related to these health benefits. We hypothesized that reg-
ulating of iron homeostasis may play a pivotal role in the bio-effects of cranberry. Here
we have tested the ability of quercetin, one of the major flavonoids found in cranberries,
to inhibit free radical formation via iron-chelation mechanism. Iron is known to catalyze
the formation of dangerous hydroxyl free radicals via Fenton Reaction. It was found that
quercetin can strongly chelate Fe(II) with an apparent binding constant ca. 106M−1 in
phosphate buffer at pH 7.2, and consequently attenuated Fenton Reaction. Quercetin
strongly inhibits 2-deoxyribose degradation by hydroxyl radical even at relatively high
iron concentrations and in the presence of major cellular iron chelators such as ATP and
citrate. In addition, quercetin can scavenge hydroxyl radical if formed in solution. These
results demonstrate that quercetin can effectively modulate iron biochemistry under phys-
iological conditions.
33. Single Shot Sub-Picosecond Electron Diffraction
F.M. Rudakov, D.H. Dowell, J.F. Schmerge, J.D. Cardoza, J.B. Hastings
and P.M. Weber
Depatrment of Chemistry, Brown University, 324 Brook St, Providence, RI, 02912
The time resolution of pump-probe spectroscopy is determined only by the laser pulse
duration, which can be on the order of a few femtoseconds. In contrast the time resolution
of the ultrafast electron diffraction is also limited by the electron pulse duration. The space
charge interactions of electrons within the pulse have made it difficult to obtain electron
pulses shorter than 1 ps. Our work shows that space-charge limitations can be overcome by
using relativistic electrons. We performed both experimental and computational studies
of 5 MeV electron diffraction on 160 nm thick aluminum foil using the rf-gun at the
Gun Test Facility located at the Stanford Linear Accelerator. We observed the diffraction
NSCRC 2006 35
Book of Abstracts
pattern obtained with a single electron pulse of 2 pC (107 electrons) and having a duration
of 500 fs. Our simulations show that by reducing the laser pulse duration and the charge
per pulse the time resolution of 100 fs is readily attainable.
34. Polyoxanorbornene Silica Nanocomposites
Daniel Sandberg and Thomas A.P. Seery
Department of Chemistry, University of Connecticut, 97 N. Eagleville Rd. Storrs, CT 06269
Polymer science has seen recent interest in the area of nanocomposite synthesis. The
Seery research group uses Grubbs catalyst to grow polymer chains from tethered initia-
tors on silica nanoparticles. Efforts to date show evidence of backbiting reactions. This
process either cleaves a ring polymer leaving an active catalyst on the surface or creates a
loop on the surface and releases a chain fragment with active catalyst present at both ends
of the polymer chain. This undesired side reaction placed limitations on both the brush
density and molecular weight of polynorbornene chains that could be grown in this fash-
ion. Altering the organic moieties of the reaction was a suggested means of inhibiting the
side reactions. If the reaction proceeds without backbiting or cross metathesis, polymer
molecular weight is expected to increase linearly as the percent of monomer converted to
polymer increases. Ongoing experiments will include the synthesis of a series of nanocom-
posites that are allowed to polymerize for different periods of time. Gel permeation
chromatography will be performed on cleaved polymer chains from these nanocomposites
to determine the molecular weight and gas chromatography mass spectroscopy will be
used to determine the percent conversion.
35. Biochemical Interactions Of the Binding Domain Of
Botulinum Neurotoxin Type A With its Receptors
Sapna Sharma and Bal Ram Singh
Department of Chemistry and Biochemistry, University of Massachusetts at Dartmouth, 285Old Westport Road, North Dartmouth, MA-02747-2300
Botulinum neurotoxins produced by seven different serotypes of Clostridum botulinum
causes flaccid paralysis by blocking the release of acetylcholine at the neuromuscular
junctions of cholinergic neurons. The exact mechanism of toxin action is unknown. We
have successfully cloned, expressed and purified the C-terminal quarter of the Heavy
chain of BoNT/A (HCQ, also known as the binding domain) and have been able to verify
its functional attributes through enzyme linked immunosorbent assay (ELISA), Western
blotting and dot-blot assay.
NSCRC 2006 36
Book of Abstracts
The significant application of this binding domain is to determine chemical compounds
such as small molecules that would inhibit its binding to neuronal cell membrane and
design vaccines that will have therapeutic effects. To meet this objective, we have in-
vestigated the interaction of HCQ with compounds such as Quinic acid and N-acetyl
neuraminic acid using competitive ELISA.
36. Metal Ions Facilitate the Folding of Alkaline Phosphatase
Amy Silverio and S.C. Pastra-Landis
Department of Chemistry, Wheaton College, Norton, MA 02766
Metal ions serve many purposes in natural proteins, from cofactors in enzymatic catal-
ysis to carriers in electron transfer. We are investigating the role of metal ions in directing
protein folding and stabilizing the tertiary structure of a metalloenzyme. In this work,
alkaline phosphatase was first unfolded in the presence of a high concentration of urea at
70 °C. The refolding process of the metalloprotein was investigated. Both native metals,
Zn2+ and Mg2+, which are known to be part of the active site of this enzyme, and other
divalent metal ions, including Mn2+, Co2+, Cu2+, and Ni2+ were found to facilitate the
refolding process of alkaline phosphatase to varying extents when they were added to
the urea heat-denatured metalloprotein. It was discovered that besides the native met-
als, Cu2+ was the most effective metal ion that assisted in the refolding process of the
enzyme. We have begun to examine whether the refolded protein samples also recover
enzymatic function; preliminary experiments are incomplete.
37. Site-Directed Mutagenesis and Characterization of
Prokaryotic and Mitochondrial Cytochrome C
Ellen M. Sletten, F. Timur Senguen, Kara L. Bren
Department of Chemistry, Stonehill College, 320 Washington St. #1369 Easton, MA 02357
Cytochrome c is a heme containing electron transfer protein found in a wide variety
of organisms. The iron center of the heme has six coordination sites: four of which are
occupied by the pyrrols of the porphyrin ring and the remaining two sites are (in class
one) occupied by histadine and methionine residues. Recently, it has been discovered
that some cytochromes c display fluxion of the iron methionine coordination. While the
fluxion in select cytochromes c has been verified by various NMR experiments, the origin
of the fluxion has only been hypothesized. Comparison of the fluxional cytochrome c
Hydrogenobacter thermophilus (Ht) and nonfluxional cytochrome c Pseudomonas arugi-
nosa (Pa) have lead to the proposal that fluxion is suppressed by a hydrogen bond to the
NSCRC 2006 37
Book of Abstracts
methionine ligand. In order to explore this hypothesis, various site-directed mutations to
the residue that hydrogen bonds to the axial methionine are performed. The interesting
results of the HtQ64A mutant are highlighted in this presentation.
38. Development Of Catalyst Capable of Hydrolyzing
D-Ala-D-Lac Termini Of Antibiotic Resistant Bacteria
T K Subrahmanian Alfio Fichera and Krishna Kumar
Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, MA, 02155
The Vancomycin family of glycopeptide antibiotics work by interfering with bacterial
cell wall biosynthesis. Vancomycin acts by binding a terminal dipeptide intermediate in
cell wall biosynthesis, D-Ala-D-Ala, tightly (Kd 1 mM) thereby preventing the action of
crosslinking enzymes that provide structural rigidity to the cell wall. Vancomycin resistant
bacterial strains have recently emerged and pose significant threats to human health.
The resistant bacteria alter their terminal dipeptide to the D-Ala-D-Lac depsipeptide,
which reduces the binding affinity of Vancomycin by 1000 fold. We have developed a
series of small molecules with nucleophilic groups capable of hydrolyzing the ester bond
and re-sensitizing resistant bacteria to Vancomycin. We report here the synthesis and
antimicrobial activity of a series of such compounds.
39. Synthesis and Reactivity of Cationic Molybdenum
Alkylidene Compounds Supported by Diketonate and
Diketiminate Ligands
Zachary J. Tonzetich, Annie J. Jiang, and Richard R. Schrock
Department of Chemistry, MIT, 77 Massachusetts Ave, Cambridge, MA 021239
The chemistry of molybdenum imido alkylidene compounds has been developed with
both b-diketonate (acac) and b-diketiminate (nacnac) supporting ligands. These species
provide an interesting compliment to the traditional Schrock-type metathesis catalysts
supported by two alkoxide ligands. Entry into the chemistry involves reaction of a bis-
triflate precursor with the alkali metal salt of the acac or nacnac ligand to afford com-
plexes of the type Mo(NAr)(CHCMe2Ph)(LˆL)(S)(OTf) (Ar = 2, 6− iPr2C6H3; LˆL
= TMHD, S = THF, quinuclidine, 2,4-lutidine; LˆL = HFAC, S = THF; LˆL = NˆNMe =
[2, 6−Me2C6H3NC(Me)]2CH, S = none; LˆL = NˆNCl = [2, 6−Cl2C6H3NC(Me)]2CH,
S = none). The triflate ligand in these compounds can be removed with sodium borate
salts to give rare examples of cationic imido alkylidene species. The solid-state structure
NSCRC 2006 38
Book of Abstracts
of two such cationic species, Mo(NAr)(CHCMe2Ph)(TMHD)(THF )BArF4(ArF =
3, 5− (CF3)2C6H3) and Mo(NAr)(CHCMe2Ph)(NˆNCl)BArF4, has been determined
by X-ray diffraction. The preliminary metathesis chemistry of these species has also been
probed with simple olefins such as ethylene and shown to resemble that of the parent
bis-alkoxide catalysts.
40. Progress Toward the First Chemical Synthesis of a Single
Walled Carbon Nanotube
Vikki M. Tsefrikas and Lawrence T. Scott
Department of Chemistry, Boston College, 2609 Beacon Street, Chestnut Hill, MA 02467
Carbon nanotubes have unique molecular structures that grant them the potential
to be revolutionary electronic and chemical materials. However, further exploration of
their properties requires a uniform and reproducible nanotube sample with a specific
diameter and ring-orientation. Therefore, progress is being made towards the chemical
synthesis of a [6,6] arm-chair single walled carbon nanotube with 6-fold symmetry. The
strategy undertaken involves the synthesis of a C60H12 hemispherical endcap, which will
subsequently be elongated to the desired nanotube.
The synthetic pathway includes regioselective functionalization of the polycyclic aro-
matic hydrocarbon dibenzo[a,g]corannulene, catalytic homocoupling of the C28H14 bowl
and cyclodehydrogenation to a C56H24 symmetrical dimer. Installation of the final four
carbon atoms by a double Diels-Alder reaction across the bay regions of a perylene moiety,
and precedented pyrolysis of an anhydride precursor will afford the target endcap. The
curved building block, dibenzo[a,g]corannulene, has been successfully synthesized by two
independent routes employing similar precursors: 1) flash vacuum pyrolysis and 2) double
intramolecular Heck reactions.
41. Intramolecular Michael Additions: Studies Toward the
Total Synthesis of Salvinorin A
NSCRC 2006 39
Book of Abstracts
Grace C. Wang, Jonathan R. Scheerer and David A. Evans
Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St.,Cambridge, MA 02138
The most potent naturally-occurring hallucinogen, salvinorin A (1) is a selective kappa-
opioid receptor agonist and a potential medicinal candidate for diseases characterized
by hallucinosis or altered perception. No total synthesis has been reported to date.
Retrosynthetic disconnections of salvinorin A at C5C10 and C8C9 suggest that total
synthesis could be achieved from either a linear malonate precursor (2) or a macrocyclic
precursor (3) through an intramolecular cyclization cascade.
A model system (4) was developed to investigate stereoselective Michael reaction con-
ditions for conversion to lactone 5a. After a survey of bases, solvents, and temperatures,
the methyl malonate 4 in 1:2 THF/DMF solution gave optimal results (d.r. greater than
95:5).
NSCRC 2006 40
Book of Abstracts
42. Nitroxide-Mediated Polymerization Using New
Alkoxyamine Initiators
Qing Xia and Robert B. Grubbs
Department of Chemistry, Dartmouth College, 6128 Burke Laboratory, Hanover, NH 03755
Nitroxide mediated radical polymerization of n-butyl acrylate was studied by using
the new alkoxyamine initiator DMAP. In order to avoid working with the corresponding
unstable free nitroxide, a low percentage of which is necessary for controlled polymeriza-
tion, a strategy involving in situ generation of free nitroxide has been developed. By first
preheating the initiator for a certain period of time and then adding in the monomer,
low polydispersity poly(n-butyl acrylate) was obtained (Mw/Mn lower than 1.40) as op-
posed to the polymerization process without preheating (Mw/Mn higher than 3). The
decomposition of the alkoxyamine initiator was studied at different temperatures by us-
ing EPR. Another new alkoxyamine was also synthesized by the addition of 1-phenylethyl
radicals to N-tert-butyl-a-phenylnitrone. Its role as an initiator in the nitroxide mediated
polymerization is till under investigation.
43. Determination of Bisphenol A in Water Contacted With
Plastic Using HPLC With Fluorescence Detection
J.T.Yukica W.W.Fogelman, A.B.Waghe
Chemical, Earth, Atmospheric and Physical Sciences Department, Plymouth State University,MSC 48,Plymouth, NH 03264
Bisphenol A (BPA) is a component in the preparation of polycarbonate plastics and
epoxy resins. This plastic is often used to make food containers and beverage bottles.
BPA is linked to hormone-disrupting effects in human cells and mice, and some studies
have shown that there may even be risk associated with relatively low-doses. In this study
we attempt to determine the amount of BPA released from Nalgene brand bottles. Both
nanopure water and methanol equilibrated with the polymer for 2 days at 2 different
temperatures released measurable amounts of BPA. Results indicated that the amount of
BPA released in alcohol and water depends on both pH and temperature.
44. Peptide Mimics of DNA
Deniz Yuksel and Krishna Kumar
Department of Chemistry, Tufts University, 62 Talbot Avenue, Medford, MA, 02155
NSCRC 2006 41
Book of Abstracts
Prokaryotic organisms defend themselves against phage attack via several ways, one
of which is the employment of restriction-modification (R-M) systems. However, the R-
M system is not perfect; phage and some plasmids found ways to deceive the system.
A striking example is found in phage T7 where its 0.3 gene product -an anti-restriction
protein- inhibits Type I R-M enzymes. The structure of Ocr protein with the arrange-
ment of its negative charges and its bent shape is unique in its mimicry of B-DNA. The
Ocr protein exhibits a nice example of molecular mimicry and demonstrates that despite
all their differences it is possible to achieve structural similarity between proteins and
DNA. Previously, dimeric, two-helix, three-helix and four-helix bundles have been de-
signed and characterized to create native-like proteins. Here, we propose a new design
paradigm where a dimeric two-helix helical bundle is decorated with the required pattern
of aspartate and glutamate residues to create a DNA-mimicking protein like Ocr.
45. Photochemical Reduction of CO2 by Sphalerite (ZnS)
Colloidal Particles and the Origin of Life
Xiang V. Zhang, Scot T. Martin, Cynthia M. Friend, Heinrich Holland,
F.M. Michel, Martin Schoonen
Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford St.,Cambridge, MA 02138
Photochemical reduction of CO2 on mineral surfaces could have contributed signifi-
cantly to carbon fixation on prebiotic Earth and the growth of long-chain organic mole-
cules. We demonstrate that under UV irradiation colloidal particles of sphalerite (ZnS)
chemically reduce aqueous CO2 to form organic molecules (“prebiotic soup”). Measure-
ments of total organic carbon show that photoproducts other than formate also form,
which implies the formation of carbon-carbon coupling products. The likely presence of
sphalerite colloidal particles in the oceans of the prebiotic Earth suggests that photo-
chemical reactions on their surface could have played a significant role in the prebiotic
synthesis of organic molecules.
NSCRC 2006 42
Book of Abstracts
Author Index
Note: Presenting authors shown in bold
AUTHOR AFFILIATION PAGE
Aditya, S. Emmanuel College 16
d’Alarcao, M. Tufts University 20
Allakhverdiyeva, Y. Emmanuel College 16
Ambrose, J. L. University of New Hamp-
shire
16
Atanassova, V. University of Massachusetts,
Boston
17
Benoit, J. Wheaton College 17
Bonzagni, A. Wheaton College 17
Brace, L. Emmanuel College 16
Bren, K. L. Stonehill College 37
Brush, E. Bridgewater State College 22, 31
Butler, P. Tufts University 18
Cabrera, T. M. Simmons College 18
Cardoza, J. D. Brown University 35
Ceby, P. Tufts University 26
Cho, M. Tufts University 18
Clark, G. Tufts University 19
Collins, B. C. Bridgewater State College 20
Dafik, L. Tufts University 19
Delaney, J. MIT 21
DeMott, J.C. Brandeis University 11
DeSosua, R. University of Massachusetts,
Boston
17
Dowell, D. H. Brown University 35
Drennan, C. MIT 21
Ellison, H. Wheaton College 29
Erbeck, A. Bridgewater State College 22
Esquibel University of Massachusetts,
Boston
30
Essigmann, J. MIT 21
Evans, D. A. Harvard University 39
Continued on the next page
NSCRC 2006 43
Book of Abstracts
AUTHOR AFFILIATION PAGE
Fan, L. Brandeis University 23
Fichera, A. MIT 38
Flaherty, M. Emmanuel College 16
Flook, M. M. Tufts University 22
Fogelman, W. W. Plymouth State University 41
Foxman, B. M. Brandeis University 11
Frick, L. MIT 21
Friend, C. M. Harvard University 42
Frigugrietti, L. M. Simmons College 18
Gabert, A. J. MIT 14
Glueck, D. S. Dartmouth College 12
Gregor, L. C. Brandeis University 23
Groenzin, H. Tufts University 28
Grubbs, R. B. Dartmouth College 12, 41
Guo, G. Brandeis University 11
Guo, M. University of Massachusetts,
Dartmouth
35
Gurney, R. M. Simmons College 18
Haefner, S. G. Bridgewater State College 20, 28, 29
Hammond, P. T. MIT 14
Hastings, J. B. Brown University 35
Holland, H. Harvard University 42
Horan, F. A. Plymouth State University 24
Hummel, J. T. Stonehill College 24
Jiang, A. J. MIT 38
Johnson, L. L. Boston University 25
Kaplan, D. Tufts University 34
Kennedy, D. P University of New Hamp-
shire
25
Korendovych, I. K. Tufts University 18, 26
Kryatov, S. V. Tufts University 26
Kumar, K. Tufts University 19, 20, 30, 38, 41
Landge, S. M. University of Massachusetts,
Boston
27
Lane, S. M. Bridgewater State College 28
Continued on the next page
NSCRC 2006 44
Book of Abstracts
AUTHOR AFFILIATION PAGE
Li, I. Tufts University 28
Liotta, L. J. Stonehill College 13, 24
Lortie, L. Wheaton College 29
Losey, H. C. Harvard University 14
Magruder, H. Wheaton College 17
Martin, S. T Harvard University 42
Mayne, H. R. University of New Hampshire 16
McDonald, L. T. Bridgewater State College 29
Meng, H. Tufts University 30
Mhadgut, S. C. University of Massachusetts,
Boston
30, 32
Michel, F. M. Harvard University 42
Mofford, D. Bridgewater State College 31
Mohammed, A. University of Massachusetts,
Boston
32
Mueller, A. A. Harvard University 14
Ozerov, O. V. Brandeis University 11, 23
Palluchio, T. D. Bridgewater State College 33
Panek, J. S. Boston University 14
Pastra-Landis, S. C. Wheaton College 37
Pearl, J. Bridgewater State College 33
Pendergraph, S. A. University of Connecticut 34
Planalp, R. P. University of New Hampshire 25
Prakash, G. K. S. University of Massachusetts,
Boston
17
Rabotyagova, O. Tufts University 34
Raposa, E. University of Massachusetts,
Dartmouth
35
Reiff, W. M. 26
Rheingold, A. L. University of New Hampshire 25
Rudakov, F. M. Brown University 35
Ruthenburg, A. J. Harvard University 14
Rybak-Akimova, E. V. Tufts University 18, 22, 26
Samson, L. MIT 21
Sandberg, D. University of Connecticut 36
Continued on the next page
NSCRC 2006 45
Book of Abstracts
AUTHOR AFFILIATION PAGE
Satuluri, K. University of Massachusetts,
Boston
17
Scheerer, J. R. Harvard University 39
Schmerge, J. F. Brown University 35
Schrock, R. R. MIT 14, 38
Scott, L. T. Boston College 39
Seery, T. University of Connecticut 36
Senguen, F. T. Stonehill College 37
Sessions, L. B. Dartmouth College 12
Sharma, S. University of Massachusetts,
Dartmouth
36
Shultz, M. J. Tufts University 28
Silvero, A. Wheaton College 37
Singh, B. R. University of Massachusetts,
Dartmouth
36
Sive, B. C. University of New Hampshire 16
Sletten, E. M. Stonehill College 13, 37
Smeester, L. MIT 21
Sotzing, G. A. University of Connecticut 34
Staples, R. J. Harvard University 18
Stutz, J. University of New Hampshire 16
Su, G. University of Massachusetts,
Dartmouth
35
Subrahmanian, T. K. Tufts University 38
Swope, S. K. Plymouth State University 24
Taghizadeh, K. MIT 21
Taktak, S. Tufts University 22
Talbot R. V. University of New Hampshire 16
Tonzetich, Z. J. MIT 38
Torok, B. University of Massachusetts,
Boston
17, 27, 30, 32
Torok, M. University of Massachusetts,
Boston
17, 30, 32
Tsefrikas, V. M. Boston College 39
Verdine, G. L. Harvard University 14
Continued on the next page
NSCRC 2006 46
Book of Abstracts
AUTHOR AFFILIATION PAGE
Verploegen, E. MIT 14
Waghe, A. B. Plymouth State University 24, 41
Wang, G. C. Harvard University 39
Waratuke, S. A. Bridgewater State College 33
Weber, P. M. Brown University 35
Wei, Y. University of Massachusetts,
Dartmouth
35
Wishnok, J. MIT 21
Wong, C. MIT 21
Utz, A. L. Tufts University 11
Xia, Q. Dartmouth College 41
Yavuz, M. S. University of Connecticut 34
Yukica, J. T. Plymouth State University 41
Yuksel, D. Tufts University 41
Zhang, X. V. Harvard University 42
NSCRC 2006 47