Chemistry Commons^™

Development Of A Green Method For Amide Synthesis, Megan Ruth Darragh

Undergraduate Honors Thesis Collection

The aim of this work was to determine the scope and limitations of using microwave technology, solvent-free conditions and green chemistry-applicable solid supports for amide synthesis. We hypothesize that the method developed by Comerford et al [12] may be applicable to other solid support systems already in use (silica, fly ash, and alumina), and that combined with the use of microwave technology, green and efficient synthesis of varied amides and other dehydration reaction products may be possible. These methods should show application to undergraduate, organic chemistry laboratories as well as large-scale production laboratories.

The Proliferation Of Vascular Smooth Muscle Cells Depends On Thioredoxin 1 Protein In A Model Of Pulmonary Hypertension, Viktoria Nelin

Mahurin Honors College Capstone Experience/Thesis Projects

Pulmonary hypertension (PH) is a disease which manifests itself in the lungs of both adults and children. Vascular proliferation and remodeling are the hallmarks of PH and are found mainly in the pulmonary arterial smooth muscle cells (PASMC). The cause of PASMC proliferation and vascular remodeling in PH is poorly understood. Hypoxia, or low oxygen content, underlies many forms of PH. Hypoxia results in alterations in the redox balance of the PASMC. Therefore, the aim of this study was to examine the role of the thioredoxin system, an antioxidant system in the cell, in hypoxia-induced proliferation in PASMC. Protein was …

Assessing Social Benefits Of Domestic Rainwater Harvesting In Southern Kenya, Lindsey M. Filiatreau

Mahurin Honors College Capstone Experience/Thesis Projects

In the Kasigau location of the Voi District of Kenya, severe rainwater shortages closed fourteen water collection stations in 2008 and 2009, leaving ten water sources to service 15,000 people in the region. Few families in the area have domestic rainwater harvesting systems which are an easily implemented, low-cost means of water collection. I investigated the ability of rainwater catchment systems to modify family time budgets (by reducing water collection time) and lessen the severity of water scarcity (by supplying families a significant amount of water). Forty families participated in the research, 20 of whom received free installation of a …

A Stereoselective Hydroxylation Step Of Alkaloid Biosynthesis By A Unique Cytochrome P450 In Catharanthus Roseus, Lesley Ann Giddings, David K. Liscombe, John P. Hamilton, Kevin L. Childs, Dean Dellapenna, C. Robin Buell, Sarah E. O'Connor

Chemistry: Faculty Publications

Plant cytochrome P450s are involved in the production of over a hundred thousand metabolites such as alkaloids, terpenoids, and phenylpropanoids. Although cytochrome P450 genes constitute one of the largest superfamilies in plants, many of the catalytic functions of the enzymes they encode remain unknown. Here, we report the identification and functional characterization of a cytochrome P450 gene in a new subfamily of CYP71, CYP71BJ1, involved in alkaloid biosynthesis. Co-expression analysis of putative cytochrome P450 genes in the Catharanthus roseus transcriptome identified candidate genes with expression profiles similar to known terpene indole alkaloid biosynthetic genes. Screening of these candidate genes by …

Chemistry - Acs Certification, Daniel Hinson

Mahurin Honors College Capstone Experience/Thesis Projects

Heterocyclic organic and organometallic compounds (e.g. polypyrrole, Figure 1A) and their derivatives have been of great interest for conductive polymers due to their novel properties, such as their versatile structure and ease of synthesis. In addition, these molecules have a great environmental stability compared to non-aromatic analogs (e.g. polyacetylene, Figure 1B). We have been interested in synthesizing organometallic pyridazyl (Figure 1C) complexes for polymer research. Figure 1. Structures of A–D. Pyridazyl complexes of rhenium were synthesized in three steps beginning from 1,2-diacylcyclopentadienes (aka, fulvenes, Figure 1D). Synthesis, characterization and molecular structure of [Mn(CO)3{1,2-C5H3(CC4H3ON)(CC4H3ON)}] (4A), [Re(CO)3{1,2-C5H3(CC4H3ON)(CC4H3ON)}] (4B), and their precursors are …

Asimafoetidnol: A New Sesquiterpenoid Coumarin From The Gum Resin Of Ferula Assa-Foetida, Debasish Bandyopadhyay, Manas Banerjee, Subrata Laskar, Bidyut Basak

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Chemistry)

Chemical investigation of the gum resin of Ferula assa-foetida L. resulted in the isolation of a new sesquiterpenoid coumarin, 7-(((E)-5-((1S,3S,6S)-3,6- dihydroxy-2,2,6-trimethylcyclohexyl)-3-methylpent-2-en-1-yl)oxy) -2H-chromen-2-one (asimafoetidnol), together with several other known compounds. The structure of asimafoetidnol was established on the basis of spectroscopic analyses. Geometry optimization of the compound has been carried out using a DFT/B3LYP/3-21G* method.

Dna Sequence Variation In The Wingless Gene Product In Buckeye Butterflies (Genus Junonia), Bonnie Mccullagh

Mahurin Honors College Capstone Experience/Thesis Projects

Wingless is a highly conserved gene important to cell determination in development. In Drosophila, the wingless gene product has been identified as responsible for wing patterning. In Bicyclus anynana and Junonia coenia, wingless gene product is expressed in a fashion that suggests that it is involved in butterfly wing color pattern development. The wingless gene product has been implicated as a potential focal signal for patterning the eyespot of Junonia butterflies. I have shown that extensive DNA sequence variation (26.04% of the sequenced region) exists in 402 bp of wingless coding sequence among 338 specimens of Junonia from …

Screening Rnai Transformants Of Chlamydomonas For Reduced Expression Of The Photoreceptor Cryptochrome, Jeremy Webb

Mahurin Honors College Capstone Experience/Thesis Projects

Chlamydomonas reinhardtii is a unicellular green alga. In C. reinhardtii, three types of photoreceptors are known to be present: rhodopsins, phototropins, and cryptochromes. The single cryptochrome is the most likely photoreceptor for adjusting the circadian clock to the daily light/dark cycles, because cryptochromes are involved in clock entrainment in higher plants and insects. In this segment of the research, C. reinhardtii strains, which were genetically modified through transformation with a RNA interference construct, were screened for reduction in cryptochrome compared to the control strain. After C. reinhardtii cultures were harvested in complete darkness, all soluble proteins were extracted from the …

Assessment Of Prenatal Care And Perinatal Outcomes In Kasigau, Kenya, Allison Smith

Mahurin Honors College Capstone Experience/Thesis Projects

The World Health Organization (WHO) implemented the Millennium Declaration in 2000 to establish global health goals to be achieved by 2015. Two of these Millennium Development Goals (MDG’s) are directly related to maternal, neonatal and child health. Healthcare during the prenatal period can help achieve the WHO MDG’s for maternal health and child mortality. Evidence has shown that women in Kenya have limited access to prenatal care. This study focused on the prenatal care and postnatal outcome trends of the women in Kasigau, Kenya. Participants were surveyed in three villages (Rukanga, Makwasinyi, and Bhuguta) to determine if prenatal care was …

Bioanalytical Screening Of Riboflavin Antagonists For Targeted Drug Delivery - A Thermodynamic And Kinetic Study, Anna Plantinga, Amanda Witte, Ming Hsin Li, Andrew Harmon

University Faculty Publications and Creative Works

The present study screened riboflavin mimicking small molecules to determine their binding activity for the riboflavin binding protein. We performed thermodynamic and kinetic binding studies of these molecules using a combination of two analytical approaches: isothermal titration calorimetry and surface plasmon resonance spectroscopy. Screening of a biased set of nonriboflavin-based small molecules by microcalorimetry led to the discovery of two known drug molecules, quinacrine and chloroquine, as favorable ligands for the riboflavin receptor with KD values of 264 and 2100 nM, respectively. We further demonstrated that quinacrine is a competitive ligand for the receptor as measured by surface plasmon resonance. …

Bioanalytical Screening Of Riboflavin Antagonists For Targeted Drug Delivery - A Thermodynamic And Kinetic Study, Anna Plantinga, Amanda Witte, Ming Hsin Li, Andrew Harmon

University Faculty Publications and Creative Works

The present study screened riboflavin mimicking small molecules to determine their binding activity for the riboflavin binding protein. We performed thermodynamic and kinetic binding studies of these molecules using a combination of two analytical approaches: isothermal titration calorimetry and surface plasmon resonance spectroscopy. Screening of a biased set of nonriboflavin-based small molecules by microcalorimetry led to the discovery of two known drug molecules, quinacrine and chloroquine, as favorable ligands for the riboflavin receptor with KD values of 264 and 2100 nM, respectively. We further demonstrated that quinacrine is a competitive ligand for the receptor as measured by surface plasmon resonance. …

Growth Mechanisms Of Complex Organics In The Gas Phase And On Metal Nanoparticles Generated By A Laser Vaporization Process, Abdel Rahman Soliman

Theses and Dissertations

In this dissertation, the ion mobility mass spectrometry technique is used to study the possible mechanisms of formation of polyaromatic hydrocarbons (PAHs) and polyaromatic nitrogen-containing hydrocarbons (PANHs) via the ion-molecule reactions of acetylene neutrals with different aromatic cations, in order to infer the possible mechanisms of formation of PAHs and PANHs in different environments such as interstellar media under different ionizing conditions. Furthermore, this technique is used to probe structures, address the thermochemistry, and measure the kinetics of the product ions originated from these reactions. Reactions of benzene radical cations with acetylene produce styrene and naphthalene-type cations at high temperatures. …

Development Of Free-Label Sensing In Plastic Microfluidic Platforms Using Pulsed Streaming Potentials (Psp), Vera Fernando Luna

Theses and Dissertations

This work deals with the development of a new label-free detection technique called Pulsed Streaming Potential (PSP). Its novelty relies on the adaptation of a classical electrokinetic phenomenon (streaming potential) into a tool which can evaluate molecular interplay in label-free fashion. Implementation of PSP to microfluidic platforms allowed the label-free sensing of binding events to plastic (modified and unmodified) surfaces. It was demonstrated the use of real time PSP in plastic microfluidic platforms for determination of kinetic parameters of the interaction of proteins and plastic surfaces. Moreover, initial change of PSP after adsorption of proteins showed to be proportional to …

Selective Oxidations Of Alcohols And Indoles Using The Oxammonium Cation, Joseph Qiu

Honors Scholar Theses

A general procedure for the oxidation of primary alcohols to carboxylic acids, via an aldehyde intermediate, has been developed that supplements a general procedure for the oxidation of alcohols to either aldehydes or ketones. The mechanism of the oxidation of alcohols to generate aldehydes and ketones, as well as the oxidation reaction to generate acids, was explored in a series of relative rate studies. These studies have shown selectivity in the oxammonium cation oxidations, which was demonstrated by sequential, selective oxidation of a compound possessing two different primary alcohol functionalities.

The reactions of the oxammonium cation with nitrogen heterocycles, specifically …

Determination Of Selected Heavy Metals In Some Creeks In A Tennessee City., Ann Ejimole Item

Electronic Theses and Dissertations

Concentrations of Ni, Cu, Zn, Fe, Cd, and Pb were determined in six different creeks within a city in Tennessee using Atomic Absorption Spectrophotometer. Mean concentrations of Ni, Cu, Zn, Cd, Pb, and Fe in the sites examined reveal that they exceed the USEPA recommended limits. High concentrations of Cu (0.130 mg/L), Zn (13.7 mg/L), Ni (0.267 mg/L), and Cd (0.010 mg/L) were observed in site B and Fe (3.01 mg/L) in site E relative to other sites. The concentration of Pb (0.795 mg/l) was higher in site A. Higher concentrations of Cu, Zn, and Fe were detected in samples …

Synthesis Of A Resveratrol Glycinate Derivative., Shelley Marie Van Cleve

Electronic Theses and Dissertations

Recently, the compound resveratrol has had media attention as an anti carcinogen. However, the bioavailability of resveratrol is low in the human system due to its hydrophobic nature. Therefore, it must be administered in high dosages to be effective. A plethora of derivatives have been synthesized that have the potential of resveratrol but sadly share low bioavailability. The first effort of this research was an attempt to produce a more hydrophilic ester of resveratrol. Failing this, the final product was synthesized using a glycine derivative to produce 4-[(1E)-2-(3,5-diacetyloxyphenyl)ethenyl]phenyl N-[(1,1-dimethylethoxy)carbonyl]-glycinate.

Electrochemical Studies Of Reactions In Small Volumes Less Than 1 Femto Litres., Isaac Agyekum

Electronic Theses and Dissertations

Electrochemical methods have been used to study electron transfer reactions at the interface between an aqueous phase of less than 1 femto liters in volume and a bulk organic phase. The small aqueous phase is formed at the end of a slightly recessed platinum electrode. When a negative potential is applied between the Pt electrode and the aqueous phase, Ru(NH₃)₆³⁺ in the aqueous phase could be reduced to Ru(NH₃)₆²⁺. Because the volume of the aqueous phase is very small, the electrochemically formed Ru(NH₃)₆²⁺ could instantly reach the …

Human-Wildlife Conflict On Small, Subsistence Farms In Kenya, Christopher B. Colonna

Mahurin Honors College Capstone Experience/Thesis Projects

As human populations expand, wildlife suddenly competes with humans for resources and confrontation arises as a result. Rural Africa is typical of this problem. We surveyed local owners of small farms within the five villages surrounding Mount Kasigau in Southeast Kenya to quantify losses due to wildlife depredation on both subsistence and cash crops as well as to discover the patterns and variables influencing farmer-wildlife confrontations in the region. We found no statistically significant correlations among the value of damage per acre, the distance from the bush, or the distance to the nearest water source. We did find statistical significance …

Communication: Bubbles, Crystals, And Laser-Induced Nucleation, Brandon C. Knott, Jerry L. Larue, Alec M. Wodtke, Michael F. Doherty, Baron Peters

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Short intense laser pulses of visible and infrared light can dramatically accelerate crystal nucleation from transparent solutions; previous studies invoke mechanisms that are only applicable for nucleation of ordered phases or high dielectric phases. However, we show that similar laser pulses induce CO₂bubblenucleation in carbonated water. Additionally, in water that is cosupersaturated with argon and glycine, argon bubbles escaping from the water can induce crystal nucleation without a laser. Our findings suggest a possible link between laser-induced nucleation of bubbles and crystals.

Mechanistic Study Of The Small Molecule Inhibitor Dx-52-1, Junru Cui

Master's Theses

Cell migration is a basic biological process that is fundamental to several normal and disease processes such as embryonic development, tissue repair, immune function, angiogenesis and cancer cell invasion and metastasis. Small organic molecules inhibiting cell migration can be used as both research probes and therapeutic agents. DX-52-1, a semisynthetic derivative of the natural product quinocarmycin (also known as quinocarcin), inhibits the migration of Madin-Darby canine kidney epithelial cells with nanomolar concentration. We have identified galectin-3, a multifunctional protein whose best-known function is its sugar binding ability, as a secondary target of DX-52-1 with functions in cell motility. In addition, …

Preliminary Analysis Of Thermally Induced Condensed Phase Electron Transfer Reactions Of Cobalt Chloride And Cobalt Bromide With Electropositive Metals, Ragini Kamineni

Student Theses and Dissertations

A non-isothermal method using TG/DTA instrument have been used to find the thermal decomposition and dehydration studies of Cobalt Chloride and Cobalt Bromide with electropositive metals like Cd, Fe, Cr, Zn and Mn under argon gas flow. The TG/DTA plots reveal that there is loss of approximately six moles of water from CoCl₂.6H₂ O and TG/DTA plot of CoBr₂ did not show any peaks and we are uncertain on thermal decomposition of CoBr₂. The change in enthalpy (ΔH) of Cobalt Chloride with metals Cd and Mn was calculated by using standard conditions because JANAF …

Calcium Carbonate And Ammonium Polyphosphate-Based Flame Retardant Composition For Polypropylene, Sarang Deodhar, Kadhiravan Shanmuganathan, Qinguo Fan, Charles A. Wilkie, Maurius C. Costache, Nicholas A. Dembsey, Prabir K. Patra

Chemistry Faculty Research and Publications

The chemical mode of action as a flame retardant of calcium carbonate nanoparticles combined with ammonium polyphosphate in polypropylene was investigated. Reduction in burning rates for 0.5 mm thick samples were observed without appreciable char formation up to 30 wt % loading of additives. Thermogravimetric analysis (TGA) of the mixture of CaCO₃ and ammonium polyphosphate (APP) showed that calcium carbonate nanoparticles react with ammonium polyphosphate before the degradation of the phosphate chains. TGA–FTIR studies of the polymer composite samples and powder mixtures of the additives confirmed the evolution of ammonia and carbon dioxide due to interaction between the additives. …

Effective And Affordable Novel Arsenic Removal Technology, Benadin Varajic

Mahurin Honors College Capstone Experience/Thesis Projects

Arsenic contaminated drinking water is a serious worldwide issue faced by millions of people every day. Long term exposure to arsenic levels above the World Health Organization’s (WHO) standard of 10 ppb has been associated with severe detrimental health effects including cardiovascular disease and cancer. Although current water purification technologies exist, their implementation is an unrealistic goal by many third world nations for a variety of reasons, the most common being the cost associated with what are typically complicated procedures. This study strives to discover an effective and affordable novel arsenic removal technology.

The first step of this study was …

Testing And Optimization Of A Cavity Ringdown Laser Absorption Spectrometer, Michael Neal Sullivan

Student Theses and Dissertations

A new cavity rindgdown spectrometer has recently been assembled within the Arkansas Center for Laser Applications and Science (ArCLAS). In order to evaluate this new spectrometer, high resolution rovibrational and rovibronic spectra have been collected for a number of molecular species including oxygen and acetylene. These spectra have been analyzed and compared with corresponding data from the literature. During the instrumental evaluation process several overtone/combination bands of 13C₂H₂ were recorded in the 13,200-13,500 cm-1 region that currently appear to be missing from the literature. Forty-three lines have been assigned for the (tentatively assigned) 2ν₂ + 3ν …

Desorption Of Volatiles From Solid Phase Micro-Extraction Using A Nd:Yag Laser, Bret Allen Yount

Student Theses and Dissertations

This work investigates the use of a Q-switched neodymium doped yttrium aluminum garnet type laser (Nd:YAG) to rapidly desorb carbowax/poly-ethylene glycol coated Solid Phase Micro-Extraction (SPME) and introduce volatile samples to a GC-MS. Specifically, effort is made to reduce desorption cycle time from an order of minutes to seconds, enhance SPME lifetime by minimizing degradation of coating material during desorption, and reduce overall desorption energy and size requirements while also minimizing the concern for SPME oxidation in air. Experiments with a 1064 nm laser pulse, utilizing both toluene and DNT as the compound of interest, demonstrate that laser pulses can …

Towards The Synthesis Of Alpha-Aminogalactosylceramides, Shaun C. Christian

Master's Theses

No abstract provided.

Unprecedented Directing Group Ability Of Cyclophanes In Arene Fluorinations With Diaryliodonium Salts, Joseph W. Graskemper, Bijia Wang, Linlin Qin, Kiel D. Neumann, Stephen G. Dimagno

Stephen DiMagno Papers

For the first time it is shown that exceptionally electron-rich arene rings can be fluorinated exclusively during the reductive elimination reactions of diaryliodonium fluorides. The 5-methoxy[2.2]paracyclophan-4-yl directing group simultaneously reduces unproductive aryne chemistry and eliminates ligand exchange reactions by a combination of steric and electronic effects. Use of the cyclophane directing group permits an unprecedented degree of control in fluorination reactions of diaryliodonium salts.

Includes Supporting Information (50 pp.)

Chemistry In Second Life. Part 1. A World Of Visualisation, Andrew Lang, Jean-Claude Bradley

College of Science and Engineering Faculty Research and Scholarship

The multi-user virtual environment of Second Life is not limited tothe realms of role-play or romance. It can be a platform for the interactive and collaborative visualisation of molecules, spectraand experimental data.

Ruthenium-Based Olefin Metathesis Catalysts Bearing Ph-Responsive Ligands: External Control Of Catalyst Solubility And Activity, Shawna Lynn Balof

Dissertations

Sixteen novel, Ru-based olefin metathesis catalysts bearing pH responsive ligands were synthesized. The pH-responsive groups employed with these catalysts included dimethylamino (NMe₂) modified NHC ligands as well as N-donor dimethylaminopyridine (DMAP) and 3-(o-pyridyl)propylidene ligands. These pH-responsive ligands provided the means by which the solubility and/or activity profiles of the catalysts produced could be controlled via acid addition. The main goal of this dissertation was to design catalyst systems capable of performing ring opening metathesis (ROMP) and ring closing metathesis (RCM) reactions in both organic and aqueous media.

In an effort to quickly gain access to new …

Innovative Purification Protocol For Heparin Binding Proteins: Relevance In Biopharmaceutical And Biomedical Applications, Sumit Batra

Masters Theses & Specialist Projects

Heparin binding (HB) proteins mediates a wide range of important cellular processes, which makes this class of proteins biopharmaceutically important. Engineering HB proteins could bring many advantages, but it necessitates cost effective and efficient purification methodologies compared to the currently available methods. One of the most important classes of heparin binding protein is the fibroblast growth factors (FGFs) and its receptors (FGFRs). In this study, we report an efficient off-column purification of FGF-1 from soluble fractions and purification of the D2 domain of FGFR from insoluble inclusion bodies, using a weak amberlite cation (IRC) exchanger. This approach is an alternative …