Chemistry Commons^™

Α-Hydroxyhippuric Acid Derivatives: Ph-Dependent Aqueous Kinetics And Buffer Catalysis., Kati Feken

Theses and Dissertations

Synthesis and kinetic investigations of the aqueous breakdown of α-hydroxyhippuric acid derivatives as a function of pH were performed to acquire an understanding of the reactivity of this biologically relevant carbinolamide functionality.

Reactive Pathways In The Chlorobenzene–Ammonia Dimer Cation Radical: New Insights From Experiment And Theory, Scott A. Reid

Chemistry Faculty Research and Publications

Building upon our recent studies of noncovalent interactions in chlorobenzene and bromobenzene clusters, in this work we focus on interactions of chlorobenzene (PhCl) with a prototypical N atom donor, ammonia (NH₃). Thus, we have obtained electronic spectra of PhCl···(NH₃)_n (n = 1–3) complexes in the region of the PhCl monomer S₀ −S₁ (ππ*) transition using resonant 2-photon ionization (R2PI) methods combined with time-of-flight mass analysis. Consistent with previous studies, we find that upon ionization the PhCl···NH₃ dimer cation radical reacts primarily via Cl atom loss. A second channel, HCl loss, is …

Photoelectron Imaging Of Iodide Centered Alkyl Halide Cluster Anions, Joshua S. Lasinski

All Theses and Dissertations (ETDs)

This dissertation presents results from cluster anion photodetachment experiments of the solvated iodide anion as a means of investigating electron molecule interaction. Due to the localization of the excess charge on the iodine atom, these experiments proceed analogously to electron scattering experiments, in that exposure to sufficient photon energy detaches the electron, which may or may not interact with the target molecule before being detected. Such interactions are related to temporary electron capture into the σ* orbital of the target molecule.

This dissertation begins with an analysis of the previously published I−·CH3X: X = I, Br, Cl) photodetachment results. These …

Development Of A New Sugar Receptor, William D. Thomas, Dr. Paul B. Savage

Journal of Undergraduate Research

Oligosaccharides are enormously rich in structural information. They are often branched and can be bonded together by a variety of different linkages, unlike polypeptides which contain identical peptide bonds.1 For this reason, polysaccharides play a crucial role in cell recognition.2 Although carbohydrate recognition is known to take place, the event is not well understood.3 In order to better understand the hydrophobic interactions that enhance binding between sugar based receptors and various small hydrophobic molecules in aqueous solvents, the synthesis of a glucose based cavity was attempted (see Fig. 3). The cavity was carefully designed to maximize hydrophobic interactions with small …

Optimization Of Polymer Separation By Gradient Polymer Elution Chromatography, Gideon R. Liem, Linda Nien-Hwa Wang

The Summer Undergraduate Research Fellowship (SURF) Symposium

High Performance Liquid Chromatography (HPLC) has been a versatile separation method for polymers for many years. Analysis of different polymers by HPLC is typically done by utilizing the differential solubility of the polymers by mixing a good solvent and an anti-solvent in various compositions. This method is called Gradient Polymer Elution Chromatography (GPEC). While GPEC has been used extensively, it commonly uses a linear gradient to separate components. Linear solvent gradients consume a lot of solvent and take a relatively long time (> 30 minutes) to complete. The goal of this study is to develop a step gradient from a …

Investigating Intermolecular Interactions In Crystalline Aspirin Using Cdft, Nicholas Turner, Tonglei Li, Mingtao Zhang

The Summer Undergraduate Research Fellowship (SURF) Symposium

Drugs today are widely administered in their crystalline form, namely via tablets and capsules. The crystal structure of a drug molecule affects important drug qualities such as solubility, bioavailability, shelf life, and compaction properties. In order to form a basis for crystal structure prediction, it is necessary to first understand how intermolecular interactions cause molecules to pack in certain ways. Being able to predict and perhaps even control a drug molecule’s crystal structure will lead to the development of higher quality drugs that perform more consistently. Scientists and engineers do not fully understand the reasons for a molecule assuming a …

Investigation Of Major Intermolecular Interactions In 7,8-Dihydrobenzo(K)Phenanthridin-6(5h)-One Crystal Using Quantum Calculations And Crystallographic Visualization Programs, Zhiwei Liao, Tonglei Li, Mingtao Zhang

The Summer Undergraduate Research Fellowship (SURF) Symposium

Currently, tablets and capsules are the most common ways of delivering drugs. The active pharmaceutical ingredients and excipients used to make those tablets and capsules are in their crystalline form generally. However, a single molecule can form multiple different crystal structures because of different packing arrangements of the molecules. These different crystal structures have identical chemical composition but different properties such as solubility, density, stability, etc. This phenomenon is called polymorphism. Occurrence of polymorphism could be a disaster for both patients and pharmaceutical companies, as the drug could lose its efficacy due to changes in properties. Studying intermolecular interactions in …

Catalytic Methyl Transfer From Dimethylcarbonate To Carboxylic Acids, Yuan Ji, Jessica Sweeney, Jillian Zoglio, David J. Gorin

Chemistry: Faculty Publications

Although methylation reactions are commonplace, currently used reagents are hazardous, toxic, and/or unstable. Dimethylcarbonate has been put forth as an inexpensive, nontoxic, and “green” potential methylating reagent. Herein we report a general, base-catalyzed methyl transfer from dimethylcarbonate to carboxylic acids. High selectivity for esterification is observed even in the presence of unprotected phenols, and the mild reaction conditions enable conservation of stereochemistry at epimerizable stereocenters. Isotope-labeling studies suggest a mechanism proceeding by direct methyl transfer from dimethylcarbonate to the substrate.

The Role Of Rgs16 In Germinal Center T Cells, Aaron Lewis, Dr. Gregory Burton

Journal of Undergraduate Research

RGS16 is an inhibitor of the chemokine receptor, CXCR4, and HIV uses CXCR4 to infect CD4+ T cells. CXCR4 is upregulated in germinal center (GC) T cells even though RGS16 is present in GC T cells

Surface Modification Of Poly(Dimethylsiloxane) With 254 Nm Irradiation:A Comparison Of Functional Groups, Kenya Wallace

Von Braun Symposium Student Posters

No abstract provided.

Synthesis And Characterization Of Novel Amino-Retinoid A4-Spermine, Jeffrey Swallow, Dr. Heidi Vollmer-Snarr

Journal of Undergraduate Research

Age Related Macular Degeneration (AMD) is the leading cause of vision loss in developed countries. The accumulation of lipofuscin in the eye causes death of the retinal pigment epithelium (RPE) leading to blindness (1,2). The lipofuscin chemical A2E has been shown to have cytotoxic effect in RPE, yet much of lipofuscin has remained uncharacterized (3). We have shown that other compounds exist in lipofuscin through preliminary mass spectroscopy (MS) and high-pressure liquid chromatography (HPLC) data collected from lipofuscin samples. Our lab is working to first characterize these lipofuscin compounds and then we will also study their oxidative products in order …

Production Of A Novel Anti-Tumor Chemotherapy Agent, Jeffrey Stephens, Dr. Merrit Andrus

Journal of Undergraduate Research

Cancer is a condition unlike any other known to man. It is one of the leading causes of death in the United States. In 2000, over 500,000 deaths resulted from various cancers.1 This has led to an extensive search for improved ways to treat cancer, and has left a daunting challenge to develop new ways to treat this condition. The natural product Geldanamycin (GA), the most potent of the benzoquinone absamycin antibiotics, has shown to have great promise as an anti-tumor agent. The analog of Geldanamycin, 17-Allylanino-GA, is currently in clinical trials2, and the first total synthesis of GA was …

Retinal-Bio-Amine Synthesis Related To Age-Related Macular Degeneration, Matthew Sparks, Dr. Heidi Vollmer-Snarr

Journal of Undergraduate Research

Age-related Macular Degeneration (AMD) is the leading cause for blindness among the world’s elderly population1. As the central region of the retina, known as the macula, is damaged and begins to deteriorate, central vision becomes clouded. This vision loss progresses until the affected person becomes completely and permanently blind. To date, AMD is an incurable disease.

Investigate And Study Of The Properties Of 2,2-Dipicolyamine And It Interactions With Anions, Martin Conda Sheridan, Dr. John Lamb

Journal of Undergraduate Research

Compared to cation ligand interactions, anion ligand studies are less well known. We studied the interactions of protonated cavitands, Fig 1, with anions because of their many applications, including: environmental waste remediation, anion separation, binding constant determination, and molecular structure recognition.

Stereo-Selective Photochemical [2+2] Cycloaddition: Π-Π Interactions Or Radical Stabilization, Alexander Parent, Dr. Steven Fleming

Journal of Undergraduate Research

Organic chemistry centers around the stereo- and regioselective formation of C–C bonds. Although [4+2] and [2+2] cycloadditions present the opportunity for single-step creation of multiple stereocenters and two C–C bonds, the products resulting from intermolecular cycloadditions can be hard to predict and yields of any single isomer can be low. These obstacles can be overcome by the use of a removable tether, which induces regio- and stereo-control through the forced intramolecular reaction. The silyl acetal-tethered [2+2] photocycloaddition has been shown to produce high yields of a single product when both of the reacting alkenes contain extended p-systems. This phenomenon is …

Cadmium Specific Ion Sensor, David Michaelis, Dr. Paul Savage

Journal of Undergraduate Research

In recent years it has become critical to detect and monitor concentrations of heavy metal ions in the environment. Cadmium and other heavy metals have detrimental effects to human health. The main difficulty of sensing these ions is selectively detecting the ions in the presence of other naturally present metal ions such as calcium, zinc, and copper. Fluorescent molecular sensors provide an ideal solution to the problem. These organic sensors can be constructed to selectively bind with target metal ions. While many such sensors exist today, little work has been done to incorporate such sensors into portable sensing devices.

Isolation, Structure Identification And Cytotoxic Studies Of Biologically Active Compounds In Carica Papaya Of Ghana, Kurtis S. Staples, Dr. Steven G. Wood

Journal of Undergraduate Research

Carica papaya, commonly known as the papaya plant, is found in large abundance throughout the tropical regions of the planet. The fruit of the plant has been extensively studied with papain, a protease, being the center of research. Preliminary studies showed that compounds found in the leaves of the plant possessed anti-cancer properties. As alternatives for cancer treatment are constantly being sought, plant extracts have risen to the forefront in this hunt.1 An understanding of the structure and mode of activity of the compounds in this plant will further knowledge of how to develop chemotherapeutic agents.

Synthesis Of Hiv Integrase Inhibitors, Carl Jones, Dr. Matt A. Peterson

Journal of Undergraduate Research

We have made significant progress toward the synthesis of one branch of the library of compounds that we plan to synthesize. The scheme we have followed is shown below. Once synthesized, we plan to have the compounds tested by expert collaborators to see how well they bind HTLV integrase. In addition, they will be tested against many viruses and cancers, as well as HIV. Because they are nucleoside based, it is impossible to predict exactly what type of biological activity these compounds will have. They could possibly treat a variety of diseases.

Thermodynamics Of Titanium Oxide Nanoparticles, Marcus Donaldson, Dr. Juliana Boerio-Goates

Journal of Undergraduate Research

I studied the thermodynamics of titanium oxide nanoparticles using adiabatic and semi-adiabatic calorimetry.

Preferential Infection Of Germinal Center T Cells By X4 Tropic Hiv, Christopher M. Cherry, Dr. Gregory F. Burton

Journal of Undergraduate Research

HIV infects CD4 T cells through binding to CD4 and an appropriate co-receptor. Two co-receptors of concern in HIV biology are CXCR4 and CCR5 because of their affect on disease progression. The majority of transmittable HIV strains use CCR5 as a co-receptor. However, during the latter stages of disease the virus may shift from using CCR5 to using CXCR4 as its co-receptor. This change is referred to as a shift in tropism, and it is of major concern because it leads to rapid disease progression (3). The site and mechanism by which this shift occurs still elude scientists. Recent findings …

Understanding Isolated Systems Of Hard Spheres, Scott Burt, Dr. Randy Shirts

Journal of Undergraduate Research

Chemical modeling is an increasingly important tool in modern research. Despite vast improvements in computational speed, most systems of interest are so complex that simulations must be carried out on model systems that are much smaller and simpler than the system of interest. However, such simplified systems often contain constraints that do not apply to the larger system. This causes significant deviations from the true behavior of the corresponding macroscopic system. Such deviations are known as finite size effects. Understanding these effects are important for correctly extrapolating simulation results to the macroscopic system of interest. For example, chemical simulations are …

Pressure Perturbation Calorimetry, Blair R. Brown, Dr. Earl M. Woolley

Journal of Undergraduate Research

In Dr. Woolley’s lab we have made extensive measurements of the Apparent Molar Heat Capacities of aqueous solutions using a Nano Differential Scanning Calorimeter, N-DSC (Calorimetry Science Corporation, Spanish Fork, UT). Through modifications to the N-DSC we are now able to do pressure perturbation calorimetry. That is to say we may now change the pressure of a solution and measure the change in the heat of that solution, (dq/dP)T ( as opposed to (dq/dT)p which is heat capacity). This property is related to entropy by the 2nd law of thermodynamics in the following way (dq/dP)T = T(dS/dP)T. From a Maxwell …

Understanding The Secretion Of Histamine, Sean P. Brady, Dr. Paul B. Savage

Journal of Undergraduate Research

With help from fellow lab members, this project involved the synthesis of several antigen linkers in order to aid the understanding of histamine secretion of basophil cells. It is hypothesized that the bi-valent linkers (such as the ones outlined below) do not stimulate basophil cells, but that the tri-valent antigens (not shown in this report) do cause granulation of cells.

Use Of Cationic Steroid Antibiotics To Fight Drug Resistance In Gram-Positive And Gram-Negative Bacteria, Thomas Orsak, Dr. Paul Savage

Journal of Undergraduate Research

Drug resistance has become an increasing problem for clinical anti-bacterial needs and a major human health threat. Drug resistance emerges through structural or biochemical pathway changes that antibacterial drugs specifically target. Bacteria have the ability to rapidly mutate and gain resistance to antibacterial drugs because of their ability to reproduce rapidly. However some parts of bacterial cells need to stay consistent. The need for consistency for these parts arises from their complexity and their essential biological activities. One of these parts is the bacterial membrane.

The Localization Of Cationic Steroid Antibiotics In Escherichia Coli Through Transmission Electron Microscopy, Matthew Chadwell, Dr. Paul Savage

Journal of Undergraduate Research

The growing numbers of antibiotic resistant bacteria has caused concern in the health community. To combat this enemy, our lab has developed an arsenal of new compounds called cationic steroid antibiotics (CSAs). To date, many of these compounds have successfully killed bacteria resistant to common antibiotics. Although we have successfully killed these bacteria, the question still remains as how this occurs. If we could identify the mode of action by which these compounds kill bacteria, then scientists would be able to develop more effective CSAs.

Identification Of Binding Partners For Phosducin, Tiffany Sabin, Dr. Barry Willardson

Journal of Undergraduate Research

Cellular signaling is vital to the proper functioning of a cell. In the visual system, as light activates the transmembrane receptor rhodopsin, a series of signals is initiated throughout the cell. This response begins with the activation of G proteins which couple to the rhodopsin. One important player in G protein signaling is Phosducin (Pdc). The unphosphorylated form of Pdc binds to the βγ subunit of the G protein.1 We used a proteomics approach to investigate the possibility of other binding partners for Pdc.

Cataracts And Na,K-Atpase, Ryan Earp, Dr. Steven Graves

Journal of Undergraduate Research

Nearly 20.5 million Americans above the age of 40 suffer impaired vision caused by cataracts. By the age of 80, the percentage of Americans suffering from cataracts increases to 50%. According to the World Health Organization cataracts are the leading cause of blindness in the world. The United States government spends an estimated $3.4 billion annually to treat cataracts surgically. The enormous cost of cataract treatment suggests a great need for non-invasive cataract treatment.

Corrections To The Virial Expansion For Finite Hard Sphere Systems, Aaron M. Johnson, Dr. Randall B. Shirts

Journal of Undergraduate Research

Computer modeling has become an important aspect of modern chemistry. As chemists try to better understand the how and why of chemical reactions, computer modeling and simulation is unparalleled in value. We are able to learn the conditions that best facilitate effective collisions, and therefore, the best way to design chemical synthesis. However, in order for these simulated results to be most accurate, chemists need to understand how the simulations relate to real systems. Limited by computation speed and programming complexity, simulated systems are always much smaller than real systems in both volume and number of particles. The purpose of …

A2e-Dna Interaction: A Possible Mechanism For Dna Damage, Sierra Evelyn Dabell, Dr. Heidi R. Vollmer-Snarr

Journal of Undergraduate Research

A2E, a common fluorophore found in the retinal pigment epithelial cells of the eye has been shown to have phototoxic properties. For this reason A2E has been implicated in the progressive etiology of Age-related Macular Degeneration (AMD). If the mechanism of cell death can be understood, a possible intervention can be produced. Moreover, the benefits of researching A2E are two-fold. An understanding of bisoxirane-DNA interactions holds the possibility of revealing information about the pathology of AMD and presents itself as a possible chemotherapy through photo-dynamic therapy.

The Role Of A2e In Amd And Chemotherapy, D. Joshua Cameron, Dr. Heidi Vollmer-Snarr

Journal of Undergraduate Research

A2E is implicated in the etiology of AMD. We have found significant concentrations of A2E present in both lipofuscin and melanolipofuscin of human retinal pigment epithelial (RPE) cells, meaning that A2E is likely more involved in AMD than originally thought. Evidence shows that A2E, in small concentrations, is not cytotoxic alone, but becomes toxic when exposed to blue light. The light mechanism involved in A2E toxicity can be controlled and used to trigger cytotoxicity in cancer cell lines. The implications of A2E in AMD and the applications of A2E’s light triggered cytotoxicity as a possible chemotherapeutic treatment were further elucidated …