Physical Sciences and Mathematics Commons^™

Mechanisms And Applications Of Improved Protein Analysis By Desorption Electrospray Ionization Mass Spectrometry (Desi-Ms), Roshan Javanshad

Dissertations

Electrospray ionization mass spectrometry (ESI-MS) is a soft ionization technique that allows detection of macromolecules, such as intact proteins, by the formation of multiply charged ions from solutions. Desorption electrospray ionization mass spectrometry (DESI-MS) is an ambient ionization technique that directly samples analyte from a surface during ESI-MS analysis. Although DESI-MS is highly accomplished at the analyses of metabolites, lipids, and other small molecules, it is far more limited when it comes to protein analysis. While most of the field in ambient ionization MS has moved towards primarily applications, our approach has been to explore the use of DESI-MS and …

Synthesis And Characterization Of Novel Organic Ligands With Their Complexes Of Platinum, Copper And Uranium, Mustafa Adnan Yasin Aldulaimi

Dissertations

Transition metal complexes of symmetrical and asymmetrical Schiff bases have played a significant role in the field of coordination, inorganic, and bioinorganic chemistry as models for biological, analytical, industrial, and pharmaceutical applications. Over recent years a great deal of interest has developed in new transition metal complexes of Schiff base ligand. The preparation of novel organic ligands is the most important step in the development of metal complexes that exhibit unique properties and novel reactivity. To highlight the presentation of this dissertation and to provide more detailed investigations, the dissertation was separated into six chapters according to the sequence of …

Best Organic Chemistry Practices In The Midwest, Claire Van Der Bosch

Honors Theses

Organic Chemistry is a gateway course to a handful of courses in higher chemical education. Unfortunately, it is notorious for its high-fail, high-withdrawal, and high-drop rate and has a reputation for being time-consuming, with difficult concepts that are oftentimes new to students. It is often taught in a two-semester sequence, with the courses named Organic I and Organic II, and both courses have a lab component. At Western Michigan University, the fail rate for these two courses are 53.5% and 36.9%, respectively. Most higher education institutions are certified with the American Chemical Society (ACS) and given a skeleton of a …

Organocatalyzed Synthesis Of Epoxides From Chalcones Utilizing Amino Acids, Sabrina N. Kegeler

Masters Theses

The epoxide functional group is important throughout the chemical and pharmaceutical industries, as well as in nature. In the chemical industry, epoxides are present in resins and fragrances. In the pharmaceutical industry, epoxide-containing compounds are used as intermediates in the manufacturing of drugs. In nature, many natural products contain epoxide groups and are used for medicinal purposes, and for models to create synthetic molecules.

One approach to epoxide synthesis involves the use of an alkene precursor, a base, and an oxidizing agent. This is where my investigations began. The first step was to optimize the epoxidation reaction, examining substrate scope, …

Application Of Electrospray Ionization Mass Spectrometry For Ionic Liquids And Their Biodegradation Products, Sepideh Rahbarirad

Masters Theses

Ionic liquids (ILs) are organic salts with unique physico-chemical properties and are used as green alternatives to volatile organic solvents. ESI-MS is a sensitive technique to detect these stable, permanent ions. My research focused on (1) Identification of biodegradation products of ionic liquids and (2) Multiplexed tandem MS by modulation of ionization efficiency.

Studies, have demonstrated that ILs are toxic to the environment, which makes their biodegradability an important consideration. In this work, metabolites generated during the biodegradation of 1-butyl-3-methylimidazolium chloride (BMIM), a degradation resistant and commonly used ionic liquid, are identified using high performance liquid chromatography-mass spectrometry (LC-MS).

Multiplexed …

Probing The Unfolding And The Stability Of The Last Four Metal Binding Domains Of Wilson Disease Protein Using Circular Dichroism And Novel Spectroscopic Techniques, Ibtesam Yaseen Alja’Afreh

Dissertations

Wilson disease protein is a copper-transporting P_1B type ATPase. It has large N-terminal copper binding domain which is composed of six homologous sub-domains. Each of these six domains is ~72 residues and connected to one another by linking regions of various lengths. They all possess similar ferrodoxin fold, and metal-binding motif, MXCXXC.

The need of having six metal binding domains and the manner in which they are communicating with each other is not well understood. To better understand how the last four metal binding domains function, I pursued a detailed biophysical characterization of these domains. Using molecular biology I …

Ultrafast Interfacial Electron Transfer Across Molecule-Tio2 Nanocomposites: Towards Solar Cells And Two Photon Absorption, Edwin Mghanga

Dissertations

Interfacial charge transfer (ICT) across the molecule-TiO2 nanoparticle interface has gained enormous research attention for applications in dye sensitized solar cells (DSSC), photo-catalysis, water splitting and nonlinear optics. DSSCs are promising clean alternative energy sources. However, current DSSCs suffer from lower efficiencies and higher cost. Better understanding of the ICT processes in DSSCs can help solve these problems. We have used two strategies to understand ICT in the context of DSSCs. Firstly, we used a computationally validated anchor group, acetylacetonate (acac) to bind molecules to the semiconductor surface and facilitate charge separation. Secondly, we used natural dye sensitizers, …

Fundamental Studies Of Protein Ionization For Improved Analysis By Electrospray Ionization Mass Spectrometry And Related Methods, Kevin A. Douglass

Dissertations

Mass spectrometry (MS) is an analytical technique in which a sample is converted to gas-phase ions that are subsequently separated and detected. It offers great speed, selectivity, and sensitivity during analysis, characteristics which have enabled it to become a leading method for the study of proteins. The applications of MS for these biologically significant macromolecules range from accurately determining identity and sequence to shedding light on post-translational modifications and protein-molecule interactions. As a first step towards analysis by MS, gas-phase protein ions must be formed. A common method for ionization is electrospray ionization (ESI), where a liquid sample including the …

Using Soil Organic Matter As An Iron Chelate To Enhance The Efficiency Of Modified Fenton Oxidition Of Diesel Fuel In Arctic Soils, Mary K. Sherwood

Masters Theses

Laboratory experiments were conducted to investigate the use of modified fenton chemistry on the treatment of three soils from the Canadian arctic, all with abundant soil organic matter, iron and manganese oxides, and diesel fuel contamination. The purpose of these studies was to (I) to assess modified fenton chemistry as a treatment option for petroleum-contaminated arctic soils, and (2) to evaluate the impact of soil organic matter on the modified fenton treatment of soils. Modified fenton treatment was compared for reactions in which ethylenediaminetetraacetate was added as a chelate vs. reactions in which the native soil organic matter was the …

Molecularly Woven Materials From Metal-Organic Precursors, Gellert Mezei, Jaafar Hachem, Isurika R. Fernando, Natasha R. Wadhwa, Neil C. Hughes

Faculty Research and Creative Activities Award (FRACAA)

No abstract provided.

Electron Transfer In Electrophilic Aromatic Nitration And Nitrosation, Yirong Mo, Zhenhua Chen

Faculty Research and Creative Activities Award (FRACAA)

No abstract provided.

Metal-Organic And Supramolecular Architectures Based On Mechanically Interlocked Molecules, Isurika Rosini Fernando

Dissertations

The focus of this work is on mechanically interlocked molecules (MIMs), which have unusual physicochemical and mechanical properties with potential applications in nano-scale/molecular devices and high strength materials.

Rotaxanes, for example, consist of an axle-like molecule threaded through a wheel-like molecule, with bulky groups at the two ends of the axle preventing the wheel from dissociating. The position of the wheel along the axle can be switched in a controllable and reversible manner by applying external stimuli, a feature that might lead to the next generation of computers. Molecularly woven materials (MWMs), another example of molecules with mechanically interlocked features, …

The In-Situ Removal Of Menthofuran From Peppermint Oil And Subsequent Reactions Of The Solid-Supported Adduct, Robert Joseph Justice Ii

Dissertations

Menthofuran is an aromatic heterocyclic compound found naturally in the essential oil of Mentha piperita L. or peppermint. Natural peppermint oil may contain between approximately 2 to 8% menthofuran.

Peppermint oil is a complex mixture of over 350 identified chemical compounds; market demands dictate the extent of processing the oil undergoes prior to being introduced into consumer goods. Menthofuran has long been known to readily autoxidize, either alone or within the peppermint oil matrix, leading to a discolored oil with negative organoleptic consequences that adversely affects its commercial viability. Therefore, a facile method for selective removal of menthofuran was developed …

Nickel Catalyzed Cyclizations Of Alkynyl-Etones And Their Application To The Formal Synthesis Of Pentalenic Acid, Kevin Schlosser

Honors Theses

Pentalenic acid is a very important molecule because it is a biosynthetic intermediate of pentalenolactone, which has antibiotic effects on Grampositive/ negative bacteria and pathogenic fungi. These effects are due to its ability to inhibit glyceraldehyde 3-phosphate dehydrogenase.1 However, the total synthesis of pentalenic acid is very lengthy.2 This project will begin the process of finding a more convenient route to pentalenic acid. Previously in this laboratory there have been experiments conducted in the cyclization of enones with nickel (0)3 It is hypothesized that this method can be used to shorten the preparation of pentalenic acid. As illustrated by the …

A Hplc Method To Assay Mycotoxins - Fumonisin, Ochratoxin And Zearalenone, Nalini Sadagopan

Masters Theses

A HPLC method to quantitate the mycotoxins Fumonisin B1 (FB1), Ochratoxin A(OA), and Zearalenone (ZON) was developed and validated. Mycotoxins are secondary metabolites of fungi like Fusarium, Asperigillus and Penicillium that contaminate crops. They have a wide array of chemical structures which facilitate their analytical detection.

The analytical method consists of reverse phase chromatography and fluorescence detection. Sample cleanup was performed using SAX and C18 cartridges prior to analysis on the HPLC.

The method developed for FB1 is unique in that it is more sensitive, accurate, and reproducible than the existing methods. Automation is one of the salient features that …

Investigation Of Electron Transfer From Carbonylmetallate Anions To Electron Acceptors, Joseph Kofi Agyin

Masters Theses

This study investigated electron transfer potential of the carbonyl-metallate anions cyclopentadienylirondicarbonyl and methylcyclopentadienyliron-dicarbonyl anions to the electron acceptors 2,2-dinitropropane, 1,1-dinitrocyclohexane, $\alpha$,p-dinitrocumene, methyl cyclopentadienyl-mercury(II) chloride and iodide.

The findings from this study indicated that: (a) the expected products could not be obtained from reactions of the anions with the dinitro-substrates, and (b) the mercurials reacted with the anions but the expected products, (ferrocene and methylferrocene), was the minor product and an unexpected (methyl) cyclopentadienylirondicarbonylmercury(II)-chloride or iodide was the major product.

Synthesis Of Symmetric And "Mixed-Ligand" Homocyclopentadienyl Ruthenocenes, John Adjeiku Amanfu

Masters Theses

No abstract provided.

Synthesis Of Organometallic Polymers, Po-Chang Chiang

Masters Theses

By the middle of the nineteenth century, organic chemists found high molecular weight compounds as by-products of some of their experiments. These compounds were thought of as products of a failed reaction. It was not until sixty years ago that the first polymers were deliberately synthesized. Today polymers are used in almost every facet of life and they are becoming more important with each passing day.

This research project focused on synthesizing conducting organometallic polymers. By linking aromatic rings with transition metals, the resultant polymers should have good electrical conductivity because of the interaction of (a) the p electrons on …

Reductive Cleavage Of Cyclopentadienylmanganese Tricarbonyl, Mani S. Iyer

Masters Theses

Since the isolation of ferrocene in 1951, it has been shown to behave like benzene and may be acylated, sulfonated, metalated, and arylated. Like benzene, it also resists hydrogenation.

Daniel Trifan and Louis Nicholas (1957) were the first to show that ferrocene can be smoothly degraded by lithium and ethylamine. The isolation of free cyclopentadienyl ion on hydrolysis of the reaction mixture indicates that the cleavage leads initially to cyclopentadienyl lithium salt. A similar procedure applied to cyclopentadienylmanganese tricarbonyl also resulted in the formation of cyclopentadienyl lithium salt. This, when added to ferrous chloride, gave ferrocene. This technique can be …

Micellar Catalysis Of Hydrolysis Of Substituted Hydroxamic Acids With Perfluorooctanoic Acid, Zhongyuan He

Masters Theses

The work demonstrated the effects of differently located and substituted phenyl groups, as well as aliphatic groups in the hydroxamic acids, on micellar catalysis with perfluorooctanoic acid as the reactive counterion surfactant in aqueous acetonitrile solution.

Kinetic rate constant-surfactant concentration profiles for the decano-, 2,5-dimethylphenylaceto-, 4-isopropylphenylaceto-, 4-phenylbutano-, and 6-phenyl-hexanohydroxamic acids were examined and analysis on the data obtained were reported.

The pseudo-phase ion exchange (PPIE) model has been satisfactorily applied to explain the observed micellar effects.

Further investigation into more appropriately substituted hydroxamic acids is suggested in order to obtain a more complete set of data and further evaluation.

Micellar Catalyzed Hydrolysis Of Hydroxamic Acids By Perfluorooctanoic Acid, Mohammad Hashem Akhavan Tafti

Masters Theses

The work reported herein demonstrated that a perfluorocarboxylic acid does indeed behave as a reactive counterion surfactant exhibiting micellar catalysis, this conclusion was further verified by subsequent experimentation.

Rates of acidic hydrolysis of octano-, phenylaceto-, and 4-bromo phenylacetohydroxamic acid have been determined in aqueous perfluorooctanoic acid--a reactive counterion surfactant system. Typical micellar catalysis was observed for the hydrolysis of octanohydroxamic acid but not for the arylacetohydroxamic acids.

Further investigation into finding a more water soluble surfactant which has reactive counter ions is suggested in order to test the theoretical equation (based on the pseudo phase model) appropriate for this surfactant …

Synthesis And Reactions Of A-Diketones And Preparation Of Some New Benzimidazoles, Mohamad Reza Agharahimi

Masters Theses

This report will discuss the synthesis of 2,5-dl-(p-chlorophenyl)-3,4-dioxoadiponitrile and its reactions. This compound exists in the form of 4,4'- dichloropulvinic nitrile which is a precursor to 4,4'-dichk>rovulpinic acid. These compounds have been shown to have antiinflammatory activity in rats.

The benzimidazole and pyridazine derivatives of 4,4'-dichioropulvinic nitrile and the benzimidazole derivative of 4,4'-dichk>rovuipinic acid are another group of compounds that are also believed to have useful biological activities. The Pinner synthesis of imidates is used to make the intermediate to the benzimidazole derivative of 4,4'-dichloropulvinic nitrile.

This report will include the methodology of the reactions and …

A Synthetic Approach To Novel Heterocyclic Herbicides, Paul Antony Pathadan

Masters Theses

The purpose of this research study was to prepare novel heterocyclic herbicides. The first phase of the project was to synthesize 1-(nitromethyl)-4-phthalazone.

In the second phase 1 - (nitromethyl)-4-phthalazone was treated with 1,3-propane-dithio-di-p-toluene sulfonate in presence of sodium hydride to get the target compound 4-(1'-nitro-l,3-dithiane)phthalazone.

It is believed that this compound might block the electron transport system of aerobic cells¹ . So further investigation of this compound may lead to novel herbicides.

Synthesis And Study Of Novel Quinoxaline Di-N-Oxide And 3-Acyl-2-Methylquinoxaline Di-N-Oxides, Cyprian Okwara Ogbu

Masters Theses

This research project consists of two parts. The first involved the synthesis of a novel quininoxaline di-N-oxide via benzofuroxan. The second part was the use of this compound as a synthetic precursor.

It was assumed that 3,4-dimethylaniline would be successfully converted to 5,6-dimethybenzofurazan 1-oxide (5,6-dimethybenzofuroxan) through a sequence of reaction steps. Fortunately, this assumption was correct as the desired compound was produced. This compound was utilized in synthesizing the novel 3-acetyl-2,6,7-trimethylquinoxaline 1,4-dioxide. From the structure of this adduct, it is believed that it will take part in condensation reactions associated with methyl ketones without disrupting the quinoxaline di-N-oxide framework, and …

The Preparation And Reaction Of Novel Glycosyl Ureas And Thioureas, Robert Scott Johnson

Masters Theses

No abstract provided.

Synthesis Of Pyridine Nucleosides By Cycloaddition Reactions And Synthesis And Condensation Reactions Of 4-Aryl-2-Oxytetronimides, Glenn L. Heise

Masters Theses

Experiment 1: The reaction of various glutaconaldehyde salts (Na⁺ or K⁺) with glycosyl isothiocyanates has resulted in the formation of a novel class of compounds. Relatively mild conditions were utilized for the synthesis which occurs in four steps, and in good yield, starting from glucpseptentaacetate. These reactions were found to be regiospecific. The unique physical and spectral properties of the model compound 1-(2,3,4,6-tetra-0-acetyl-β-D-glycopranosyl)-2-thiono-3-pyridine carboxaldehyde are also discussed.

Experiement 2: Early synthetic methodologies have recently been utilized in the synthesis of 4-aryl-2-oxytetronimides. These compounds have been found to participate in condensation reactions with various substituted o-phenylene diamines. A …

Reactivity Of Some Nitrogen-Containing Compounds At Supercritical Water Conditions, David M. Tiffany

Masters Theses

The use of water at cuperctirical conditions to remove nitrogen from several nitrogen-containing compounds was studied with the purpose of exploring the use of supercritical water as a method of removing nitrogen from the extraction products of coal. Quinoline and isoquinolone were the primary model compounds used with benzonitrile and carbazole also being examined briefly. Reaction conditions varied in temperature (350-500°C), pressure (3500-5200 psi), and water density (0.170-.0.426g/cc). The major products formed by isoquinoline were benzene, toluene, ethylbenzene, and o-xylene as well as nonvolatile tar and char. Quinoline produced aniline and toluidine in addition to those obtained from isoquinoline. Most …

Heterocyclic Syntheses Utilizing Aryl Cyanates, Joseph Eugene Drumm

Masters Theses

No abstract provided.

Naphthalene-2,3-Dialdehyde: A Synthon To 7,9-Polymethylene-8h-Cyclohepta[B]Naphthalene-8-One And A Study Of Their Aromaticity, Edward O. Crapps

Dissertations

This report describes the synthesis of naphthalene-2,3-dialdehyde, and an analytical method for determining its purity by thin layer chromatography. Subsequently, the dialdehyde was condensed with various cyclic ketones to generate a series of polymethylene bridged naphthotropones. It was found that planarity and aromaticity increase with the size of the methylene bridge, although, the bridge must contain six or more methylene groups for the latter to be true. The claim for aromaticity is supported by NMR and IR data, which indicates the positive charge for a perchlorate cation salt is delocalized over the naphthalene and tropone ring system. Furthermore, from the …

Cationic And Anionic Micellar Catalyzed Hydrolysis Of Hydroxamic Acids, Douglas Eugene Conran

Masters Theses

The hydrolysis of octanohydroxamic and N-methyloctanohydroxamic acids in the presence of cationic and anionic micelles was investigated. Rate constants were determined for the hydrolyses in cetyltrimethylammonium bromide (ctab), the cationic surfactant, with 0.1111 N NaOH and in sodium 1-dodecanesulfonate, the anionic surfactant, with 0.09270 N HC1 at 50.01 + 0.11°C. The acid hydrolysis and the base hydrolysis of N-methyloctanobydroxamic acid followed the standard model for micellar catalysis.