Winter Term 2009

Ben Altheimer '12, Greensboro, NC

Advisor: Michael Nee

Winter Term Project: Synthesis of Amino-Substituted Adamantanes A direct method for substituting a tertiary hydrogen on an adamantane with an amide group is being investigated. Simple hydrolysis gives amino-substituted adamantanes that will be used as guests in cucurbiturils. Also being investigated is the possible introduction of a second amide group to produce diamino-substituted adamantanes.

Other Interests: physics, math, climbing, hiking, the great outdoors. 

Oheneba Amponsah

Advisor: Shara Compton

Winter Term Project: Kinetic and Thermodynamic Studies of Non-enzymatic Pyridoxal 5’-phosphate Catalyzed Reactions

Pyridoxal 5’-phosphate (PLP) is a cofactor used by a variety of enzymes in amino acid metabolism.  For example, PLP is necessary for the enzymatic interconversion of L-alanine to the enantiomeric D-alanine by the action of alanine racemase (AlaR).  Although the structure and reaction mechanism of AlaR and several other PLP-dependent enzymes are well-studied, little work has been done to investigate the thermodynamics of these enzymatic reactions.  The goal of this study is to elucidate the entropic and enthalpic contributions to non-enzymatic PLP catalysis and compare these constants to their enzymatic counterparts.  To this end, an analog of PLP, 5’-deoxypyridoxal, has been synthesized and characterized.  The analog will be used for temperature-dependent kinetic studies of its reaction with L-alanine and other amino acids substrates used by PLP-dependent enzymes.

John Andreoni ’11 Naperville, IL

Advisor: Matthew Elrod

Winter Term Project: Kinetics Studies of the Atmospheric Oxidation of Alkenes by Nitrate Radical

The nitrate radical (NO₃) is the dominant oxidant in the nighttime atmosphere.   Because both ground level ozone and aerosols are primarily photochemically produced during daytime hours, nighttime oxidation chemistry has less received less study.  We have undertaken studies of the kinetics of the nitrate radical-initiated oxidation of several atmospherically abundant alkene compounds.  We are carrying out product identification and kinetics experiments that are performed using the Turbulent Flow Chemical Ionization Mass Spectrometric (TF-CIMS) kinetics technique.

Other Interests: Aside from chemistry I also enjoy: swing dancing, a cappella, reading the New York Times, a cup of red maté tea, anything having to do with the environment, Latin American politics, reading fiction and non-fiction, SSBB, music you can groove to, running, biking, racquet sports, the color green, Italian food, foreign lands, snowboarding and amateur entomology.

Ben Baldwin ‘09, Andover, MA

Advisor: Michael Nee

Winter Term Project: Template Synthesis of Methyl-Substituted Cucurbiturils

Cucurbit[n]urils (CB[n]) are a family of macrocyclic compounds formed by the condensation of glycoluril units with formaldehyde. They are pumpkin-shaped molecules with carbonyl groups rimming the two openings and they preferentially bind cationic guests. There has been increasing interest in using molecular hosts, like cucurbiturils as molecular containers to alter the chemistry of the guest molecule, where the encapsulated guest molecule behaves differently than the free guest. Cucurbiturils also may be used in drug delivery systems.

The relatively low solubility of cucurbiturils in water and other solvents limits the utility of these molecules. Methyl substitution along the equator of cucurbiturils significantly increases the solubility of these compounds. However, so far only CB[5]s and CB[6]s have been synthesized and isolated with methyl substitution. We investigating the use of template molecules to synthesize methyl substituted CB[7]s and possibly CB[8]s.

Other Interests:  Music, the news, guitar, rugby sometimes, traveling, the outdoors, the indoors, speaking Spanish poorly, looking at maps.

Adam Birdsall ’12, Roseville, MN

Advisor: Shara Compton

Winter Term Project: Computational methodologies for determining enzyme free energy profiles.

Traditional methods for calculating free energy profiles of enzyme-catalyzed reactions rely on complex analytical mathematics and challenging kinetic experiments.  A simple method to determine microscopic rate constants would allow detailed free energy profiles of enzymatic reactions to become much more commonplace.  The goal of this project is to optimize a straightforward computational methodology for free energy profile determination that relies solely on knowledge of the enzyme’s reaction mechanism and relatively easy-to-find kinetic rate constants.   We used the kinetic simulation program COPASI to model reactions involving alanine racemase and mandelate racemase, which catalyze the interconversion of the L- and D-stereoisomers of alanine and mandelate, respectively. 

Other Interests: alphabetizing, Buster Keaton, kottke.org, math, playing piano, reading, running every street in Oberlin, sincerity, slankets, sledding, tea.

Anthony Bonifonte '11, Scranton, PA

Advisor: Cortland Hill

Winter Term Project:  Foraging Behavior in Fire Ants and Nest Architecture

This Winter Term project studied fire ant ecology at FSU with Dr. Walter Tschinkel, one of the world’s leading myrmecologists.  The project primarily consisted of three parts.  The first part involved separating ants from debris in pitfall traps taken from Appalachicola National Forest.  The second involved casting foraging tunnels and nests of fire ants, Solenopsis invicta.  The third involved surveying elevation in the forest and measuring water table depth to correlate species diversity with these characteristics.

Other Interests:   Mathematics, engineering, astrophysics, bicycling, and Capoeira.

Stephanie Bonner'12,  Newark, DE

Advisor: Cortland Hill

Winter Term Project:  Ant Biogeography of the Apalachicola National Forest

This winter term project took place in Tallahassee, FL under the direction of myrmecologist Dr. Walter Tschinkel from Florida State University. The overarching project was to assert that the local environment (the depth of the water table, the types of vegetation and the general terrain) influences the species of ants that are present in that area.  Daily activities included geographical surveying and drilling test wells in the Apalachicola National Forest, and sorting and weighing ants from pitfall traps in FSU’s ant lab with Dr. Tschinkel’s graduate students.

Other Interests: Ecology, English, Marine Biology, Human Physiology, piano, choir, photography, writing, reading, knitting.

Evan Cantu-Hertzler ‘10, Philadelphia,PA

Advisor: Cortland Hill

Winter Term Project:  Ant Species and Nest Size in Relation to Flora, Elevation, and Water Table Depth

This Winter Term project focused on the study of ant species in the Apalachicola National Forest with FSU’s Dr. Walter Tschinkel, one of the world’s leading myrmecologists.  The first project involved sorting ants out of pit fall traps and placing them in ethanol filled tubes to be counted and categorized later.  Also important to this project involved drilling holes to test water table depth, and surveying the terrain for topographic mapping.  The second project involved making aluminum and zinc casts of ant nests in the Apalachicola National Forest. 

Other Interests:  Biology, piano, soccer, visual arts, running, reading, cats.

Neil Cole-Filipiak ’10, Ypsilanti, MI

Advisor: Michael Nee

Winter Term Project: Template Synthesis of Methyl-Substituted Cucurbiturils

Cucurbit[n]urils (CB[n]) are a family of macrocyclic compounds formed by the condensation of glycoluril units with formaldehyde. They are pumpkin-shaped molecules with carbonyl groups rimming the two openings and they preferentially bind cationic guests. There has been increasing interest in using molecular hosts, like cucurbiturils as molecular containers to alter the chemistry of the guest molecule, where the encapsulated guest molecule behaves differently than the free guest. Cucurbiturils also may be used in drug delivery systems.

The relatively low solubility of cucurbiturils in water and other solvents limits the utility of these molecules. Methyl substitution along the equator of cucurbiturils significantly increases the solubility of these compounds. However, so far only CB[5]s and CB[6]s have been synthesized and isolated with methyl substitution. We investigating the use of template molecules to synthesize methyl substituted CB[7]s and possibly CB[8]s.

Other Interests: photography, Star Trek, cooking, Legos, useless trivia.

Clay Easterday  ’11, Chardon, OH

Advisor:   Jesse Rowsell

Winter Term Project: Ultraviolet/visible spectroscopic analysis of catalyst precursor solutions and determination of their saturation concentrations.

Carbon nanotubes (CNTs) have been the topic of intense scientific research since their existence was confirmed by electron microscopy in the early 1990s. With extremely high tensile strength-to-weight ratios and an array of unique electrical properties, CNTs are widely predicted to be a source of significant technological and scientific advancement. Although numerous methods for producing CNTs are documented, the procedures are often expensive, lead to highly impure products and are poorly understood mechanistically. Nanotech Innovations LLC is an Oberlin-based company with the goal of optimizing the production of multi-walled carbon nanotubes (MWNTs) using simple, cost-effective instrumentation. My current project involves the use of ultraviolet/visible spectroscopy as an analytical tool to establish the solubility of organometallic catalyst precursors in organic solvents. These solutions are then used as feedstocks for the synthesis of MWNTs using a benchtop chemical vapor deposition furnace.

Other Interests: Sleeping, peanut butter, tree climbing, science fiction, irony, world domination, singing in the rain, fancy words and keto-enol tautomerization.

Kaitlyn Gam ’10, San Francisco. CA

Advisor: William Fuchsman

Winter Term Project: The Stoichiometry of Hemoglobin- and Myoglobin-Catalyzed NAD(P)H Oxidase Reactions

Using our newly developed methods for measuring hydrogen peroxide concentrations in the presence of excess NADH and NADPH, we are examining the pH dependence of the stoichiometry of hydrogen peroxide-producing reactions of oxygen with NADH and NADPH.  We also are testing the hypothesis that deviations from the idealized 1:1 stoichiometry of NAD(P)H consumed to hydrogen peroxide produced might involve catalyzed reactions of hydrogen peroxide with NAD(P)H that produce water.

Other Interests: cooking,  open water swimming, and peer health education.

Robin Gent ’09, Cheshire, CT

Advisor:   Robert Thompson

Research Project: Development of a Colorimetric Assay for Capsaicinoids in Chili Peppers

Capsaicinoids, N-vanillyl acyl amides, are the “hot” components of chili peppers (genus Capsicum), many spicy foods, some topical pain-relief creams, and most defense sprays.  More than twenty naturally-occurring capsaicinoids are known with small, but significant differences in structure. 6-ene-8-methyl capsaicin:  There exists a need in the chili growers’ community for a simple test for the capsaicins (double-bond in the acyl chain of the capsaicinoid molecule) and non-capsaicins (all single bonds in the acyl chain).  A simple and quick test would provide growers important feedback as they attempt to breed both hotter and milder chilis.  The goal of this project is to design and develop a colorimetric method to determine capsaicin (and analogs) and dihydrocapsaicin (and analogs) in chili pepper fruits.  The extraction and separation should only require stirring and filtering, and the quantitation should only involve a color comparison.  We will begin by examining two promising color-forming reactions with the goal of understanding the reaction chemistry and identifying the colored products.

Other Interests: natural science (ie, chemistry, geology, biology, oceanography and the like), hiking, cannoeing, writing and literature.

Laura Grossi ’12, Strongsville, OH

Advisor: William Fuchsman

Winter Term Project: A New Look at an Old Reaction: The Dinitrosalicylate Assay for Reducing Sugars

The conventional wisdom that when reducing sugars react with oxidants, carboxaldehyde groups on the sugars oxidize to carboxylate groups, is inconsistent with preliminary comparisons of calibration curves for different reducing sugars, which show chain-length dependency and also differences between reducing sugars that are monosaccharides and those that are disaccharides.  We  are comparing the reactions of different reducing sugars with dinitrosalicylate and attempting to get some clues about the nature of the reaction.  Other Interests: Cello, Piano, Soccer, Biking, Reading, Scrabble, Guitar Hero.

Robin Holmes ’09, Ellicott City, MD

Advisor: Albert Matlin

Winter Term Project: Intramolecular Photocycloaddition Reactions of bis-Enones

Recently the Matlin lab has been investigating the photocyclization of bis-enone tethered by alkyl bridges of varying length to give bicyclic di-ketones.  These studies have shown that the nature of the addition (head-to-head vs. head-to-tail) and the yield varies as a function of the length of the tether.   When the tether is  -CH₂-CH₂- the cyclization produces a bicyclo[2.1.1] system but the reaction is not clean and produces several other unidentified products.  This year Robin will study the effect of rigidifying the tether using a cyclohexane group to lock the enones in a more favorable geometry for cyclization.

Other Interests: interests: running, sailing, growing plants, and wheat chex.

Serena Hsin ‘09, Phoenix, AZ

Advisor: Matthew Elrod

Winter Term Project: Kinetics Studies of the Atmospheric Oxidation of Alkenes by Nitrate Radical The nitrate radical (NO₃) is the dominant oxidant in the nighttime atmosphere. Because both ground level ozone and aerosols are primarily photochemically produced during daytime hours, nighttime oxidation chemistry has less received less study. We have undertaken studies of the kinetics of the nitrate radical-initiated oxidation of several atmospherically abundant alkene compounds. We are carrying out product identification and kinetics experiments that are performed using the Turbulent Flow Chemical Ionization Mass Spectrometric (TF-CIMS) kinetics technique.

Other Interests: Modern/ contemporary dance, dance techniques, Feve brunch, Black River Cafe coffee, biking, white peaches, blueberry picking, dresses, healthy-active lifestyle, reading short stories.

Kevin Hu ’11, New York, NY

Advisor: Matthew Elrod

Winter Term Project: Kinetics Studies of Acid-Catalyzed Reactions in Atmospheric Sulfuric Acid Aerosols Atmospheric aerosols (particles small enough to remain airborne) have an important effect on air quality and climate through their ability to scatter and absorb radiation and to serve as nuclei for cloud formation. It is now well known that these aerosols have significant organic content, despite the fact that most organic compounds in the atmosphere are expected to be too volatile to readily form condensed phase compounds. The conversion of smaller more volatile organic compounds into larger less volatile compounds via acid-catalyzed reactions has been proposed to explain this seeming contradiction. Since sulfuric acid aerosols are ubiquitous in the atmosphere, it has been proposed that these types of reactions are responsible for the build up of organic materials on aerosols. In order to address whether such reactions can take place on atmospheric aerosols, we have undertaken NMR-based kinetics studies of reactions of organic compounds in sulfuric acid solutions that are representative of atmospheric sulfuric acid aerosols.

Other Interests: triathlon training/racing, Obertones (a cappella), HIV Peer-testing, chinese calligraphy, poetry, swing dancing.

Hadley Iliff ’09, Greensboro, NC

Advisor: Catherine Oertel

Winter Term Project: Synthesis of Inorganic-Organic Compounds Based on (MoS₄^2-) Anions Hybrid inorganic-organic network materials are made up of metal atoms linked by multitopic organic ligands, which are capable of coordinating more than one metal center. Using metal clusters or complex metal anions in place of single metal ions is one way of building networks that have useful properties as well as interesting structures. Tetrathiomolybdate (MoS42-) anions are known for their ability to chelate transition metals and to act as catalysts for hydrodesulfurization and hydrodenitrogenation reactions, both of which are important in production of cleaner-burning fuel sources. We are using these complex anions as well as organic ligands and single transition metals as building blocks for network compounds. Resulting compounds could act as porous, high-surface-area catalysts.

Other interests: knitting and yarn, eating (good) food, playing cards and dominos.

Marisa Ishimatsu ’11, Lafayette, CA

Advisor: Cortland Hill

Winter Term Project: Working with Ants at Florida State University My winterterm project involved working with world-renowned myrmecologist Dr Walter R. Tschinkel. My colleagues and I assisted Dr. Tschinkel in his research. We used zinc to cast foraging ant tunnels of the invasive fire ant Solonopsis invicta, surveyed elevation and water table depth of plots in the Apalachicola National Forest, and made aluminum casts of the harvester ant Pogonomyrmex badius.

Other Interests: Ultimate Frisbee, field herpetology, hiking, canoeing, swimming, cooking, marine biology.

Ben Jakubowski ’11, St. Cloud, MN

Advisor: Albert Matlin

Winter Term Project: Photochemical and Thermal Enanantioselective Nazarov Cyclizations The classical Nazarov cyclization involves treating a cross-conjugated dienone with strong acid to produce substituted cyclopentenones. In some systems the reaction can be carried out by irradiating the dienone with ultraviolet light. In this study Ben will be trying to develop an enantioselective variant of this reaction using chiral amines (to create chiral iminium salts).

Other interests: Beyond my academic endeavors, I am interested in nature writing, folk music, and Northern Minnesota's environmental history. In my free time, I like playing guitar, backpacking, contra dancing, and reading.

Jarin Joyner '10, Atlanta, GA

Advisor: William Fuchsman

Winter Term Project: A New Look at an Old Reaction: The Dinitrosalicylate Assay for Reducing Sugars The conventional wisdom that when reducing sugars react with oxidants, carboxaldehyde groups on the sugars oxidize to carboxylate groups, is inconsistent with preliminary comparisons of calibration curves for different reducing sugars, which show chain-length dependency and also differences between reducing sugars that are monosaccharides and those that are disaccharides. We are comparing the reactions of different reducing sugars with dinitrosalicylate and attempting to get some clues about the nature of the reaction.

Other Interests: Violin and sports.

Chris Lipski ’10, Ashland, OR

Advisor: Shara Compton

Winter Term Project: Pyridoxal 5’-phosphate (PLP) is a cofactor used by a variety of enzymes in amino acid metabolism.  For example, PLP is necessary for the enzymatic interconversion of L-alanine to the enantiomeric D-alanine by the action of alanine racemase (AlaR).  Although the structure and reaction mechanism of AlaR and several other PLP-dependent enzymes are well-studied, little work has been done to investigate the thermodynamics of these enzymatic reactions.  The goal of this study is to elucidate the entropic and enthalpic contributions to non-enzymatic PLP catalysis and compare these constants to their enzymatic counterparts.  To this end, an analog of PLP, 5’-deoxypyridoxal, has been synthesized and characterized.  The analog will be used for temperature-dependent kinetic studies of its reaction with L-alanine and other amino acids substrates used by PLP-dependent enzymes.

Other Interests: Old-person card games, pretending to play tennis, swimming, jigsaw puzzles, sleeping a lot, and crosswords.

Katie Mauck ’09, Worthington, OH

Advisor: Catherine Oertel

Research Project: Corrosion of Lead-Tin Alloys: Applications to Conservation of Organ Pipes Around the world, pipes in historic organs are suffering from damaging corrosion that eventually causes formation of cracks and holes in the metal, robbing valuable instruments of their ability to produce sound. Organ pipes are most commonly made from lead-tin alloys, ranging in composition from pure lead to pure tin. We are studying corrosion of these alloys with the goal of learning how deterioration of organ pipes can be prevented or slowed. Specifically, we are studying how alloy composition affects the susceptibility of pipe metal to attack by acetic acid, which is emitted in appreciable quantities by the wood of organ cases. In addition, we are examining the role of surface deposites, such as sodium chloride, that come from an organ’s environment. We are using laboratory exposure experiments in which metal coupons of specific compositions are exposed to low, controlled concentrations of acetic acid vapor. The extent of corrosion is monitored through gravimetric analysis, and corrosion products are characterized using powder X-ray diffraction and scanning electron microscopy. Finally, in collaboration with the Center for Surface Analysis of Materials at Case Western Reserve University, we will use focused ion beam milling to carry out detailed analyses of corrosion sites.

Other Interests: art, food, French, singing, completing crossword puzzles.

Jack Miller '09 Venice Beach, CA

Advisor: Shara Compton

Winter Term Project: Kinetic and Thermodynamic Studies of Non-enzymatic Pyridoxal 5’-phosphate Catalyzed Reactions Pyridoxal 5’-phosphate (PLP) is a cofactor used by a variety of enzymes in amino acid metabolism. For example, PLP is necessary for the enzymatic interconversion of L-alanine to the enantiomeric D-alanine by the action of alanine racemase (AlaR). Although the structure and reaction mechanism of AlaR and several other PLP-dependent enzymes are well-studied, little work has been done to investigate the thermodynamics of these enzymatic reactions. The goal of this study is to elucidate the entropic and enthalpic contributions to non-enzymatic PLP catalysis and compare these constants to their enzymatic counterparts. To this end, an analog of PLP, 5’-deoxypyridoxal, has been synthesized and characterized. The analog will be used for temperature-dependent kinetic studies of its reaction with L-alanine and other amino acids substrates used by PLP-dependent enzymes.

Other Interests: Anarcho-communism, Tonality, Genuine human connection, Taoism, Origen/Palagius, Interdependence.

Emily Minerath ‘09, Ann Arbor, MI

Advisor: Matthew Elrod

Winter Term Project: Kinetics Studies of Acid-Catalyzed Reactions in Atmospheric Sulfuric Acid Aerosols Atmospheric aerosols (particles small enough to remain airborne) have an important effect on air quality and climate through their ability to scatter and absorb radiation and to serve as nuclei for cloud formation. It is now well known that these aerosols have significant organic content, despite the fact that most organic compounds in the atmosphere are expected to be too volatile to readily form condensed phase compounds. The conversion of smaller more volatile organic compounds into larger less volatile compounds via acid-catalyzed reactions has been proposed to explain this seeming contradiction. Since sulfuric acid aerosols are ubiquitous in the atmosphere, it has been proposed that these types of reactions are responsible for the build up of organic materials on aerosols. In order to address whether such reactions can take place on atmospheric aerosols, we have undertaken NMR-based kinetics studies of reactions of organic compounds in sulfuric acid solutions that are representative of atmospheric sulfuric acid aerosols.

Other Interests: Knitting, baking, reading, playing cards and dominoes, ballet and modern dance, homemade granola, watching thunderstorms, being outdoors.

Erin Moir ’11, Natick, MA

Advisor: William Fuchsman

Winter Term Project: A New Look at an Old Reaction: The Dinitrosalicylate Assay for Reducing Sugars The conventional wisdom that when reducing sugars react with oxidants, carboxaldehyde groups on the sugars oxidize to carboxylate groups, is inconsistent with preliminary comparisons of calibration curves for different reducing sugars, which show chain-length dependency and also differences between reducing sugars that are monosaccharides and those that are disaccharides. We are comparing the reactions of different reducing sugars with dinitrosalicylate and attempting to get some clues about the nature of the reaction.

Deacon Nemchick ’09, North Huntingdon, PA

Advisor: Norman Craig

Winter Term Project: Synthesis of Carbon and Deuterium Isotopomers of 1,4-Difluorobutadiene for Use in High-Resolution Infrared Spectroscopy and Structure Determinations. We seek semi-experimental structures (atoms at rest) for the cis,cis and trans,trans isomers of 1,4-difluorobutadiene to test the effect of fluorine substitution on the length of bonds in the C4 backbone. Ground state rotational constants will be derived from the analysis of the rotational structure in high-resolution spectra of a series of isotopomers. Equilibrium rotational constants will then be calculated with vibration-rotation constants obtained from ab initio quantum chemical calculations, and a structure will be fit to the set of equilibrium rotational constants. Ground state rotational constants have been secured for the two unsubstituted isomers. A sequence of steps, dependent on assembling two haloethylenes, to synthesize the isotopomers has been fully developed with non-isotopic materials and is now being applied to making the needed deuterium and carbon isotopomers.

Other Interests: Jack Bauer and Nina Meyers, skiing, ping pong, the Pittsburgh Penguins, digg.com, citrus fruits, bikes, goodies and treats, golfing, Beck, action movies, snow, coffee, Little Debbie Oatmeal Cream Pies, Rubik’s Cubes, and DeCafe sandwiches…that’s it.

Saki Nishi ’09 Kobe, Japan

Advisor: Robert Thompson

Winter Term Project: The Argentation Solid Phase Extraction of the Capsaicins

Capsaicinoids, N-vanillyl acyl amides, are the “hot” components of chili peppers (genus Capsicum), many spicy foods, some topical pain-relief creams, and most defense sprays.  More than twenty naturally-occurring capsaicinoids are known with small, but significant differences in structure. 6-ene-8-methyl capsaicin:

One of the means of separating the capsaicinoids is by argentation chromatography, in which silver ion interacts strongly with those compounds containing a double bond in the acyl chain (the capsaicins).  Argentation chromatography is usually carried out by incorporating silver ion in the stationary phase and eluting with nonpolar solvents.

Solid phase extraction (SPE) can be viewed as low pressure and low performance chromatography and is widely used to clean up samples prior to instrumental analysis. We employ argentation SPE to fractionate the capsaicinoids from chili pepper fruit (Talanta 2006, 70, 315-322). Several commercial SPE stationary phases can be used for this purpose. The goal of this project is to compare these SPE products for use in isolating the capsaicins, to measure the amount of silver that leaches from the cartridges, and to determine the efficiency of separation. Measurement techniques will include UV spectrophotometry, atomic absorption spectrophotometry,  and liquid chromatography-mass spectrometry.

Other interests: Biking, baking, shopping, languages and dogs.

Craig Packard ‘09, Wolcott, NY

Advisor: Michael Nee

Winter Term Project: Template Synthesis of Larger Cucurbiturils

Cucurbit[n]urils (CB[n]) are a family of macrocyclic compounds formed by the condensation of glycoluril units with formaldehyde. They are pumpkin-shaped molecules with carbonyl groups rimming the two openings and they preferentially bind cationic guests. There has been increasing interest in using molecular hosts, like cucurbiturils as molecular containers to alter the chemistry of the guest molecule, where the encapsulated guest molecule behaves differently than the free guest. Cucurbiturils also may be used in drug delivery systems. The larger CB[7], CB[8], and CB[10] have commensurately larger cavities and can bind potentially more useful guests. However, the yield of these larger cucurbiturils is relatively low. Our research is focused on increasing the yield of the larger cucurbiturils by the use of tight-binding guest molecules as templates for the preferential formation or stabilization of CB[7], CB[8], CB[10] and perhaps, the so far unisolated, CB[9].

Other Interests: Dry British humor, monosodium glutamate, thunderstorms, non sequiturs, rather escapist fantasy/science fiction literature, volleyball, and geography.

John E Paddock ’12, Harrison Township, MI

Advisor: William Fuchsman

Winter Term Project: A New Look at an Old Reaction: The Dinitrosalicylate Assay for Reducing Sugars The conventional wisdom that when reducing sugars react with oxidants, carboxaldehyde groups on the sugars oxidize to carboxylate groups, is inconsistent with preliminary comparisons of calibration curves for different reducing sugars, which show chain-length dependency and also differences between reducing sugars that are monosaccharides and those that are disaccharides. We are comparing the reactions of different reducing sugars with dinitrosalicylate and attempting to get some clues about the nature of the reaction.

Other Interests: Reading, languages, Japanese culture, American Indian music, piano, violin, world traveling, Irish dancing and music, fencing.

Robin Rohwer ’09, Ellicott City, MD

Advisor: Robert Thompson

Winter Term Project: The Prevalence of Bisphenol A in the Diet of Oberlin Students Bisphenol A (BPA) is a precursor chemical for many commercial products, including food and beverage can liners and reusable water bottles made from poly- carbonate plastic (recycling #7). The compound has received much recent negative press recently because it has been found to leach from containers and is a suspected agent in cancer and reproductive abnormalities. Some manufacturers are already phasing out products with BPA. An early goal of this project is to adapt a literature method for bisphenol A to our particular setting with our instrumentation. The method involves extractions followed by liquid chromatography – mass spectrometry. Once the method is in place we will examine cans and bottles in the Oberlin environment for leached bisphenol A and explore other sources of this chemical in the Oberlin student diet. We may compare cans with BPA-containing liners and those without and compare bottles made from polycarbonate and those made from other plastics.

Other interests: running, sailing, baking bread, eating fruit.

Sarah Sawtelle '12, Rye, NH

Advisor: Cortland Hill Winter Term Project: Florida State University Coastal and Marine Laboratory This Winter Term project was an opportunity to learn about and participate in the work of the marine scientists employed by the Florida State University Coastal and Marine Laboratory in St. Teresa, Florida. My experiences at the Marine Lab included assisting researchers with field work, attending lectures by both FSUCML faculty and guest speakers, and contributing to a publication being created for visitors to the lab. Throughout my stay I was immersed in the rich local ecology and exposed to the work of a wide array of marine scientists.

Other Interests: Environmentalism, Flute, Ultimate Frisbee, Japanese, Kayaking.

Clara Shaw ’10, Minneapolis, MN

Advisor: William Fuchsman

Winter Term Project: A New Look at an Old Reaction: The Dinitrosalicylate Assay for Reducing Sugars The conventional wisdom that when reducing sugars react with oxidants, carboxaldehyde groups on the sugars oxidize to carboxylate groups, is inconsistent with preliminary comparisons of calibration curves for different reducing sugars, which show chain-length dependency and also differences between reducing sugars that are monosaccharides and those that are disaccharides. We are comparing the reactions of different reducing sugars with dinitrosalicylate and attempting to get some clues about the nature of the reaction.

Savannah Sullivan '11, Goshen, OH

Advisor: Catherine Oertel

Environmentally Friendly Strategies for Dissolving Beer Stone We are collaborating with Ed Aghajanian (OC ’78), owner of EZ Brite, a Cleveland-based company the produces environmentally friendly cleaning products. The company’s customers include microbrewery operators who need to remove “beer stone,” a build-up of calcium oxalate, from fermentation tanks. Currently, dilute nitric and phosphoric acids are used to dissolve the solid, and nitrate and phosphate ions are passed into the wastewater stream. We are testing two alternative approaches for dissolving calcium oxalate. One uses ligands such as citrate and ethylenediaminetetraacetate (edta) to chelate calcium and promote dissolution of the solid. The second uses a green, commercially available “acid replacer” that could be purchased by EZ Brite to use as a component in a beer stone remover.

Other Interests: Outside, Alliteration & Rhyme, Bioluminescence, Horseback Riding, PBS, Dehydrated Bananas, Tapirs, Saunas, Lichen & Fungi, Crossword Puzzles.

Edwin Takahashi ‘09, Mililani, HI

Advisor: William Fuchsman

Winter Term Project: The Stoichiometry of Hemoglobin- and Myoglobin-Catalyzed NAD(P)H Oxidase Reactions Using our newly developed methods for measuring hydrogen peroxide concentrations in the presence of excess NADH and NADPH, we are examining the pH dependence of the stoichiometry of hydrogen peroxide-producing reactions of oxygen with NADH and NADPH. We also are testing the hypothesis that deviations from the idealized 1:1 stoichiometry of NAD(P)H consumed to hydrogen peroxide produced might involve catalyzed reactions of hydrogen peroxide with NAD(P)H that produce water.

Other Interests: Outdoor activities, track and field and football.

John Thiele ’12, Chapel Hill, NC

Advisor: Cortland Hill

Winter Term Project: Florida State University Coastal and Marine Laboratory This Winter Term project was an opportunity to learn about and participate in the work of the marine scientists employed by the Florida State University Coastal and Marine Laboratory in St. Teresa, Florida. My experiences at the Marine Lab included assisting researchers with field work, attending lectures by both FSUCML faculty and guest speakers, and contributing to a publication being created for visitors to the lab. Throughout my stay I was immersed in the rich local ecology and exposed to the work of a wide array of marine scientists.

David Tran ’10, Philadelphia, PA

Advisor: Michael Nee

Winter Term Project: Green Chemistry Experiment Development Several experiments are being tested to introduce more green chemistry into the organic laboratory program. One experiment is a Diels-Alder reaction done in aqueous rather than more typical normal organic solvents. A second experiment is a Suzuki coupling reaction also done in water and using a recyclable palladium catalyst.

Other Interests: reading, cycling, weightlifting, cooking, and gadgets.

Sydney Williams (Beckman Research Fellow) ‘09, Chico, CA

Advisor: William Fuchsman

Winter Term Project: A New Look at an Old Reaction: The Dinitrosalicylate Assay for Reducing Sugars The conventional wisdom that when reducing sugars react with oxidants, carboxaldehyde groups on the sugars oxidize to carboxylate groups, is inconsistent with preliminary comparisons of calibration curves for different reducing sugars, which show chain-length dependency and also differences between reducing sugars that are monosaccharides and those that are disaccharides. We are comparing the reactions of different reducing sugars with dinitrosalicylate and attempting to get some clues about the nature of the reaction.

Other Interests: drawing, graphic novels, listening to music.