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Articles 781 - 810 of 1398

Full-Text Articles in Chemistry

Supramolecular Coordination Networks Of S- And F-Block Metals Featuring The 1,8-Naphthalimide Tecton, Andrew Paul Leitner Dec 2015

Supramolecular Coordination Networks Of S- And F-Block Metals Featuring The 1,8-Naphthalimide Tecton, Andrew Paul Leitner

Theses and Dissertations

The reactions of (S)-2-(1,8-naphthalimido)propanoic acid (HLala), and (S)-2-(1,8- naphthalimido)-3-hydroxypropanoic acid (HLser), protonated forms of ligands that contain a carboxylate donor group, an enantiopure chiral center and a 1,8-naphthalimide π...π stacking supramolecular tecton and in the case of HLser an alcohol functional group, with the appropriate alkali metal hydroxide followed by a variety of crystallization methods leads to the formation of crystalline K(Lala)(MeOH) (1), K(Lala)(H2O) (2), Na(Lala)(H2O) (3), KLser (4), CsLser (5) and CsLala (6). Each of these new complexes has a solid state structure based on six-coordinate metals linked into homochiral helical rod SBU central cores. In addition to the …


Facile Sol-Gel Molten Salt Synthesis Of Double Perovskite La 2nimno6 As An Electrocatalyst For Oxygen Evolution Reactions, Padmini Kukkapalli Dec 2015

Facile Sol-Gel Molten Salt Synthesis Of Double Perovskite La 2nimno6 As An Electrocatalyst For Oxygen Evolution Reactions, Padmini Kukkapalli

Theses and Dissertations

Double perovskites have attracted a great attention recently for its high intrinsic activity in oxygen evolution reaction (OER) in electrochemical energy storage and conversion systems in alkaline media. In this study, we are the first to report the new approach of La2NiMnO6 double perovskite which was synthesized via Sol-gel molten-Salt synthesis method. However their stability and specific activity remain challenging that need to be addressed to meet the reqiurement for OER activities. Here in this study we synthesized three different samples with varying concentrations by taking molten salts NaNO 3 and KNO3 in (1:1) ratio such as 30:30, 60:60, 90:90. …


Advanced Data Analysis Tools And Multi-Instrument Material Characterization, Bhupinder Singh Dec 2015

Advanced Data Analysis Tools And Multi-Instrument Material Characterization, Bhupinder Singh

Theses and Dissertations

My dissertation focuses on (i) the development of new analysis tools and methodologies for analyzing X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS) data, and (ii) the comprehensive characterization of materials (nanodiamonds) using a multi-instrument approach. Chapter 1 contains (i) a discussion of the two techniques I focused on most in my work: XPS and ToF-SIMS, (ii) a discussion of the common chemometrics techniques used to analyze data from these methods, and (iii) the advantages/rationale behind the multi-instrument characterization of materials. Chapter 2 describes various good practices for obtaining reasonable peak fits in XPS, which can also …


Molecular Modeling And Mutational Mapping Of The Gpr119 Binding Site, Shane M. Askar Dec 2015

Molecular Modeling And Mutational Mapping Of The Gpr119 Binding Site, Shane M. Askar

Theses and Dissertations

GPR119 receptor’s biological role in regulating glucose homeostasis has been studied extensively. Results in the scientific literature indicate that, when activated, GPR119 releases insulin in a glucose dependent manner. Currently the 3D structure of GPR119 has not been resolved.

The goal of this research is to use a combination of homology modeling and ligand docking studies to predict the binding mode of GPR119 ligands. Amino acids implicated to have direct interactions with docked ligands will further be assessed experimentally for their roll in binding and activation of GPR119. Our results indicate that residues W2656.48 and R813.28 are likely to be …


Hand-Portable Capillary Liquid Chromatography Instrumentation, Sonika Sharma Dec 2015

Hand-Portable Capillary Liquid Chromatography Instrumentation, Sonika Sharma

Theses and Dissertations

This dissertation focuses on the development of hand-portable capillary liquid chromatography (LC) instrumentation. In this work, battery-operable nano-flow pumping systems (isocratic and gradient) were developed and integrated with portable UV-absorption detectors for capillary LC. The systems were reduced in size to acceptable weights and power usage for field operation. A major advantage of the pumps is that they do not employ a splitter, since they were specifically designed for capillary column use, thereby greatly reducing solvent consumption and waste generation. UV-absorption detectors were specifically designed and optimized for on-column detection to minimize extra-column band broadening. Initially, an isocratic nano-flow pumping …


High Flow Air Sampler For Rapid Analysis Of Volatile And Semi-Volatile Organic Compounds, Xiaofeng Xie Dec 2015

High Flow Air Sampler For Rapid Analysis Of Volatile And Semi-Volatile Organic Compounds, Xiaofeng Xie

Theses and Dissertations

Volatile and semi-volatile organic compounds are ubiquitous, and some of them are hazardous. The ability to rapidly detect and identify trace levels of them in air has become increasingly important. The conventional device used today for sampling and concentrating them in air is thermal desorption tubes filled with specific sorbents, which can only collect air samples at flow rates of 100-200 mL/min. In order to detect low concentration (ppt level) VOC compounds, long sampling time (>2 h) and sensitive detection are required. At the same time, portable instrumentation for on-site analysis has been developing rapidly. The somewhat lower performance …


Synthesis And Characterization Of Neo-Confused Porphyrins And Related Systems, Arwa Salem Almejbel Nov 2015

Synthesis And Characterization Of Neo-Confused Porphyrins And Related Systems, Arwa Salem Almejbel

Theses and Dissertations

Carbaporphyrins have been the focus of many studies, and a wide variety of related carbaporphyrinoid systems have been reported. N-confused porphyrins are a class of carbaporphyrins where one pyrrole unit has been inverted. In this work, a newly discovered family of porphyrin isomers where one of the pyrrolic subunits is connected to the meso-bridges in a 1,3-fashion, called neo-confused porphyrins, has been investigated.

Reaction of pyrrole-3-carbaldehydes with acetoxymethylpyrroles and NaH in DMF gave neo-confused dipyrrylmethane dialdehydes. The resulting dialdehydes underwent an acid catalyzed condensation with a dipyrrylmethane to give neo-confused phlorins, and following oxidation with FeCl3 afforded new neo-confused porphyrins. …


Image-Charge Detection €“ Novel Instrumentation And Applications, Brandon Lee Barney Oct 2015

Image-Charge Detection €“ Novel Instrumentation And Applications, Brandon Lee Barney

Theses and Dissertations

Image-charge detection is an analytical technique in which a highly-charged particle is detected by the magnitude of the image current that it generates in a detecting electrode. This current is represented as a voltage between the charged particle and the sensing electrode. It is a single particle detection method, ideal for the analysis of large, variable mass particles such as biological cells. Some of the physical properties of Bacillus subtilis spores were explored using different applications of image-charge detection. B. subtilis is a gram-negative spore-forming bacteria that has been shown to exhibit extremophile behavior. The particular extremophile behavior that was …


Mass Spectrometry Based Proteomics And Lipidomics Studies, Huan Kang Oct 2015

Mass Spectrometry Based Proteomics And Lipidomics Studies, Huan Kang

Theses and Dissertations

Mass spectrometry has emerged as having a vital role in various applications to biochemical fields. In this thesis, we have utilized a variety of mass spectrometry techniques for both bacteriophage proteomics and colostrum and milk lipidomics studies. Our first study was the proteome characterization of Great Salt Lake bacteriophage NS01 with SDS-PAGE GEL to separate the viral proteins and high performance liquid chromatography (HPLC) coupled with an LTQ Orbitrap to identify the proteins after in-gel digestion. In this project, we have successfully identified 11 proteins with high confidence, p-values < 0.01, including coat protein gp88 with a coverage of 91% and tail protein gp86 with a coverage of 40.96%, which facilitated the classification of NS01 as a T7-like phage. Our second study was the discovery of colostrum and milk biomarkers that can be used to predict the likelihood of development of production-related metabolic diseases (PRMDs) in dairy cows through a lipidomics approach. In this study, an electrospray ionization, time-of-flight mass spectrometer was applied to lipid profiling, quantification and significant biomolecule selection. A Q-Star quadrupole, orthogonal time-of-flight mass spectrometer and an Agilent 6530 accurate-mass quadrupole/time-of flight mass spectrometer were both used for lipid biomarker fragmentation and identification. According to linear discriminative statistical modeling, three panels of biomarkers were defined. A combination of 2 milk lipid predictors, including DG18:0/18:0 and TG 18:0/18:0/18:1, provided PRMD predictions with 75.0% sensitivity at 90.0% specificity. A combination of 3 colostrum lipid predictors, including TG16:0/18:1/18:3, DG16:0/16:0 and C40H60NO, provided PRMD prediction with 90.0% sensitivity at …


Synthesis And Characterization Of Naphthocarbaporphyrins And Related Systems, Eric Grabowski Sep 2015

Synthesis And Characterization Of Naphthocarbaporphyrins And Related Systems, Eric Grabowski

Theses and Dissertations

Carbaporphyrins are porphyrin analogs in which one of more of the pyrrole units have been replaced with a carbocyclic ring. In this project the cyclopentadiene ring replacing a pyrrole ring has been fused with a naphthalene ring. This is done in order to observe the effects of the naphthalene ring on the spectroscopic properties and reactivity.


Utilization Of Antibody-Conjugated Gold Nanoparticles, Dynamic Light Scattering And Sers In Influenza Virus Detection, Yen Hoang Lai Sep 2015

Utilization Of Antibody-Conjugated Gold Nanoparticles, Dynamic Light Scattering And Sers In Influenza Virus Detection, Yen Hoang Lai

Theses and Dissertations

Influenza A H3N2, H1N1, and influenza B viruses primarily cause winter illness in humans, leading to significant morbidity and mortality in the population of the very young, the elderly, and people with chronic disease. In addition to the regular seasonal epidemics of influenza, influenza pandemics associated with the emergence of new influenza A strains are threatening due to high levels of mortality, social disruption, and economic losses. These novel strains are not affected by the human immunity developed to older strains of influenza, therefore can spread readily and infect a vast number of people. The most recent flu pandemic outbreak …


Novel Selected Hetero-Atom Doped Carbon From Renewable Resource Materials For Fuel Cell And Supercapacitor Applications, Sunil Kumar Ramasahayam Sep 2015

Novel Selected Hetero-Atom Doped Carbon From Renewable Resource Materials For Fuel Cell And Supercapacitor Applications, Sunil Kumar Ramasahayam

Theses and Dissertations

Doped carbon materials have gained a lot of attention recently due to their wide array of applications, for example, in dye degradation, energy conversion and storage, electrocatalysis, sensors and electronics. These doped carbon materials are claimed to have a tremendous potential to substitute expensive metal based electrocatalysts in fuel cell and supercapacitor applications. A recently established microwave assisted technique, which does not make use of any inert or reducing gas during the synthesis, was utilized to synthesize doped carbon materials. The method is simple, rapid, economical and high yielding. Renewable resource materials like tannin, spent coffee grounds and thiamine were …


Preparation And Radioprotective Effects Of A Standardized Tocotrienol Containing Extract Isolated From Annatto Seeds (Bixa Orellana L.), Edith Nathalie Pineda Aug 2015

Preparation And Radioprotective Effects Of A Standardized Tocotrienol Containing Extract Isolated From Annatto Seeds (Bixa Orellana L.), Edith Nathalie Pineda

Theses and Dissertations

Currently there is no ideal radioprotective agent: one which does not show toxicity, offers long term protective effects, and is easy to administer. In this research we have developed a standardized extract of annatto, Bixa Orellana L, containing a total 60% of delta and gamma tocotrienol, in a 10:1 ratio. The extract was prepared via solvent extraction and chromatography. Radioprotective effects of the standardized extract against total body radiation were determined. Twenty-four hour before radiation CD2F1 mice received a subcutaneous injection of annatto extract a dose of 200 mg/Kg body weight. Experimental groups each received two different single radiation doses …


Understanding The Interactions Of Carbon Nanotubes With Environmentally-Relevant Ions And Hydrogen Peroxide For Optical Sensing, Azhar Abdul Kareem Kamel Aug 2015

Understanding The Interactions Of Carbon Nanotubes With Environmentally-Relevant Ions And Hydrogen Peroxide For Optical Sensing, Azhar Abdul Kareem Kamel

Theses and Dissertations

Single-walled carbon nanotubes (SWNTs) have drawn great attention in chemical and biological optical sensor applications due to their novel near infrared (NIR) optical properties that are extremely sensitive to the surrounding environment. This dissertation is devoted to four research areas: 1) Redox chemistry of sodium dodecyl sulfate (SDS)-encased SWNTs with mercuric ions in an aqueous environment for optical sensing: Various factors including SDS and SWNT concentrations, different pH levels, and buffer constituents, have been systematically examined. SWNTs show high selectivity and sensitivity to Hg2+ over eleven other metal ions. The determined detection limit is 0.6 nM, lower than 10.0 nM, …


Ribosome Component Turnover Kinetics Describes A Two-Pool Kinetic Model In Dietary Restriction That Suggests Rpl10 Is Exchanged During Ribosome Lifespan, Andrew David Mathis Aug 2015

Ribosome Component Turnover Kinetics Describes A Two-Pool Kinetic Model In Dietary Restriction That Suggests Rpl10 Is Exchanged During Ribosome Lifespan, Andrew David Mathis

Theses and Dissertations

The eukaryotic ribosome is a large molecular machine consisting of ~80 ribosomal proteins and 4 rRNAs. The 40S and 60S ribosomal subunits are assembled in the nucleolus by ~200 helper proteins then shipped into the cytoplasm or to the endoplasmic reticulum where protein translation takes place. Eventually ribosomes are removed from the cytoplasm and recycled through ribophagy, however, very is little is known about ribosomal protein exchange after assembly but before ribophagy. Using kinetic turnover measurements of ribosomal proteins and rRNA in vivo we determined ribosomal protein replacement rates are diverse suggesting ribosomal components may be replaced without destruction of …


Design, Fabrication, And Optimization Of Miniaturized Devices For Bioanalytical Applications, Suresh Kumar Aug 2015

Design, Fabrication, And Optimization Of Miniaturized Devices For Bioanalytical Applications, Suresh Kumar

Theses and Dissertations

My dissertation work integrates the techniques of microfabrication, micro/nanofluidics, and bioanalytical chemistry to develop miniaturized devices for healthcare applications. Semiconductor processing techniques including photolithography, physical and chemical vapor deposition, and wet etching are used to build these devices in silicon and polymeric materials. On-chip micro-/nanochannels, pumps, and valves are used to manipulate the flow of fluid in these devices. Analytical techniques such as size-based filtration, solid-phase extraction (SPE), sample enrichment, on-chip labeling, microchip electrophoresis (µCE), and laser induced fluorescence (LIF) are utilized to analyze biomolecules. Such miniaturized devices offer the advantages of rapid analysis, low cost, and lab-on-a-chip scale integration …


Peroxy Radical - Water Complexes: Their Role In The Atmosphere, Sambhav Rajendra Kumbhani Aug 2015

Peroxy Radical - Water Complexes: Their Role In The Atmosphere, Sambhav Rajendra Kumbhani

Theses and Dissertations

The importance of radical-water complexes in the atmosphere is explored in this dissertation. Radicals, although present in small concentrations in the atmosphere, play a significant role in creating and removing atmospheric pollution. As the atmosphere warms and consequently gets wetter, it is essential to understand the effects of water vapor on radical chemistry. This dissertation reports studies on the effects of water vapor on the kinetics of the self-reaction of β-hydroxyethyl peroxy radical (β-HEP), a prominent organic peroxy radical in the atmosphere. Both experimental and computational studies have been performed to examine the effects of water vapor on the kinetics …


Transition Metal-Olefin Bonding Interactions: A Density Functional Theory Study [ M ( Co ) X ( Æ? 2-C 2 H 3-C 6 H 4-Y) ], Michael John Berninger Jul 2015

Transition Metal-Olefin Bonding Interactions: A Density Functional Theory Study [ M ( Co ) X ( Æ? 2-C 2 H 3-C 6 H 4-Y) ], Michael John Berninger

Theses and Dissertations

Metal-olefin equilibrium geometries, bond formation energies (Î?E), enthalpies (Î?H), and free energies (Î?G) for a select series of transition (M = Ni, Fe, Cr, Mo and W) metal-olefin carbonyl complexes [M(CO)x(Æ?2-C2H3-C6H4-Y)] have been calculated and compared using density functional theory (DFT), with the BP86 functional under standard state conditions (1 atm, 298.15 K) for the general gas phase formation reaction:

M(CO)x + (C2H3-C6H4-Y) â?? [M(CO)x(Æ?2-C2H3-C6H4-Y)] (1)

Y = NO2, CN, COOH, H, OH, NH2, N(CH3)2

In regards to the electronic modification of the substituent (Y) on styrene at the para position, this study quantitatively investigated the effect of electron-withdrawing and …


The Synthesis And Characterization Of Ferritin Bio Minerals For Photovoltaic, Nanobattery, And Bio-Nano Propellant Applications, Trevor Jamison Smith Jul 2015

The Synthesis And Characterization Of Ferritin Bio Minerals For Photovoltaic, Nanobattery, And Bio-Nano Propellant Applications, Trevor Jamison Smith

Theses and Dissertations

Material science is an interdisciplinary area of research, which in part, designs and characterizes new materials. Research is concerned with synthesis, structure, properties, and performance of materials. Discoveries in materials science have significant impact on future technologies, especially in nano-scale applications where the physical properties of nanomaterials are significantly different than their bulk counterparts. The work presented here discusses the use of ferritin, a hollow sphere-like biomolecule, which forms metal oxo-hydride nanoparticles inside its protein shell for uses as a bio-inorganic material.Ferritin is capable of forming and sequestering 8 nm metal-oxide nanoparticles within its 2 nm thick protein shell. A …


Analytical Approaches In Investigating The Kinetics Of Water-Molecule Complexes In Tropospheric Reactions, William J. Keeton Jul 2015

Analytical Approaches In Investigating The Kinetics Of Water-Molecule Complexes In Tropospheric Reactions, William J. Keeton

Theses and Dissertations

Ozone is a heavily monitored pollutant. Ozone is not directly emitted into the atmosphere, but rather the product of chemical reactions. Ground level ozone occurs when nitrogen oxides (NOx) and volatile organic compounds (VOCs) react with each other in the presence of sunlight. The primary precursors of ozone are anthropogenically emitted, and as a result, tropospheric ozone has cost millions of dollars in damages and has hurt the health of countless people. This dissertation is a collection of work that aims to provide insight into atmospheric reactions that result in tropospheric ozone and the instrumentation to study such reactions. While …


Histone Deacetylase 6 (Hdac6) Is Critical For Tumor Cell Survival And Promotes The Pro-Survival Activity Of 14-3-3Ζ Viadeacetylation Of Lysines Within The14-3-3Ζ Binding Pocket, Jeffrey Benjamin Mortenson Jul 2015

Histone Deacetylase 6 (Hdac6) Is Critical For Tumor Cell Survival And Promotes The Pro-Survival Activity Of 14-3-3Ζ Viadeacetylation Of Lysines Within The14-3-3Ζ Binding Pocket, Jeffrey Benjamin Mortenson

Theses and Dissertations

Our understanding of non-histone acetylation as a means of cellular regulation is in its infancy. Using a mass spectrometry approach we identified acetylated lysine residues and monitored acetylation changes across the proteome as a consequence of metabolic stress (hypoxia). We observed changes in acetylation status of non-histone lysines in tumor cells. Through the use of small molecule inhibitors of histone deacetylase enzymes (HDACs) and siRNA screening identified HDAC6 as a pro-survival regulator of lysine acetylation during hypoxia. The phospho-binding protein 14-3-3ζ acts as a signaling hub controlling a network of interacting partners and oncogenic pathways. We show here that lysines …


Progress Towards The Total Synthesis Of Yaku'amide A, Zhiwei Ma Jul 2015

Progress Towards The Total Synthesis Of Yaku'amide A, Zhiwei Ma

Theses and Dissertations

The synthetic progress towards yaku'amide A is described. The study leads to development of new synthetic methodologies. Base-free regioselective aminohydroxylation is convenient to deliver β-tert-hydroxyamino acids. A sequence consisting of alkylative esterification, Martin sulfurane mediated anti dehydration, a tandem azide reduction-O→N acyl transfer allows the rapid access of E- and Z-dehydroisoleucine-containing peptides from β-tert-hydroxyisoleucine derivatives. Those methods are effective in constructing complicated peptides and advanced subunits of yaku'amide A.


Dna Origami Stabilized And Seeded With 4'-Aminomethyltrioxsalen For Improved Dna Nanowire Fabrication, Matthew Paul Mcdowell Jul 2015

Dna Origami Stabilized And Seeded With 4'-Aminomethyltrioxsalen For Improved Dna Nanowire Fabrication, Matthew Paul Mcdowell

Theses and Dissertations

A fast emerging technology in the microelectronics field is bottom-up self-assembly of computer circuitry. A promising method to develop nanoelectronic devices through bottom-up self-assembly is the implementation of DNA-based technologies. Using DNA to create nanoelectronic devices is advantageous because of its already well understood base-paring and annealing qualities. These base-pairing and annealing qualities can be used to design and construct DNA nanostructures called DNA origami. DNA origami are specially designed structures made from single stranded DNA. Short single stranded DNA oligonucleotides called staple strands attach to a large single stranded DNA called a DNA scaffold. DNA staple strands and DNA …


An Approach To An Agave Problem: The Bioremediation Of Agricultural Waste By Yeast Fermentations, Joshua Michael Jarodsky Jun 2015

An Approach To An Agave Problem: The Bioremediation Of Agricultural Waste By Yeast Fermentations, Joshua Michael Jarodsky

Theses and Dissertations

The agricultural waste products created by industries, such as the Tequila manufacturing industry, create thousands of tons of waste material every year. This agricultural waste often becomes an environmental and ecological problem for fields and surrounding areas. The purpose of this study is to determine the potential of using the yeast Kluyveromyces marxianus 7-1 and Kluyveromyces marxianus 8-1 to ferment the leaf waste from the harvesting of the Agave tequilana as a form of bioremediation. Fermentations (anaerobic, under constant shaking, and at room temperature) were monitored for colony forming units, pH of fermentation broth, concentration of reducing sugars, and protein …


Studies On The Roles Of Translationally Recoded Proteins From Cyclooxygenase-1 And Nucleobindin Genes In Autophagy, Jonathan J. Lee Jun 2015

Studies On The Roles Of Translationally Recoded Proteins From Cyclooxygenase-1 And Nucleobindin Genes In Autophagy, Jonathan J. Lee

Theses and Dissertations

Advances in next-generation sequencing and ribosomal profiling methods highlight that the proteome is likely orders of magnitude larger than previously thought. This expansion potentially occurs through translational recoding, a process that results in the expression of multiple variations of a protein from a single messenger RNA. Our laboratory demonstrated that cyclooxygenase-3/1b (COX-3/1b), a frameshifted, intron-1-retaining, alternative splice variant from the COX-1 gene, is multiply recoded, which results in the translation of at least seven different COX-3 proteins. Two of the recoded COX-3 proteins that we identified are active prostaglandin synthases and are inhibited by non-steroidal anti-inflammatory drugs (NSAIDs). Here we …


Synthesis, Rna Binding And Antibacterial Studies Of 2-Dos Mimetics And Development Of Polymer Supported Nanoparticle Catalysts For Nitroarene And Azide Reduction, Venkata Reddy Udumula Jun 2015

Synthesis, Rna Binding And Antibacterial Studies Of 2-Dos Mimetics And Development Of Polymer Supported Nanoparticle Catalysts For Nitroarene And Azide Reduction, Venkata Reddy Udumula

Theses and Dissertations

Project I 2-Deoxystreptamine (2-DOS), the most conserved central scaffold of aminoglycosides, is known to specifically recognize the 5'-GU-'3 sequence step through highly conserved hydrogen bonds and electrostatic interactions within and without the context of aminoglycosides (Figure 1a). We proposed that a novel monomeric unnatural amino acid building block using 2-DOS as a template would allow us to develop RNA binding molecules with higher affinity and selectivity than those currently available. Conjugating two or more of the monomeric building blocks by an amide bond would introduce extra hydrogen bonding donors and acceptors that are absent in natural aminoglycosides and increase specificity …


A Study Of Allylic Aminations As Catalyzed By Heterobimetallic Pd-Ti Complexes, Diana Lauren Ellis Jun 2015

A Study Of Allylic Aminations As Catalyzed By Heterobimetallic Pd-Ti Complexes, Diana Lauren Ellis

Theses and Dissertations

Heterobimetallic complexes present a unique approach to catalyzing challenging reactions. By having two metals in close proximity to each other, the metals are able to interact and alter their electronics in a way that simple organic ligands (carbon, nitrogen, sulfur etc.) cannot. Our studies of heterobimetallic complexes focus on a Pd–Ti complex. The complex features a dative interaction between the palladium and the titanium held together by a phosphonamide scaffold. This interaction increases the electrophilicity of the palladium and makes it a very suitable catalyst for allylic amination reactions. We have conducted extensive studies of this catalyst in allylic aminations, …


Investigation Of Oxidopyrylium-Alkene [ 5 +2 ] Cycloaddition Conjugate Addition Cascades And Extension To Chiral Auxiliary-Based Variants, Chunyin Marshall Law May 2015

Investigation Of Oxidopyrylium-Alkene [ 5 +2 ] Cycloaddition Conjugate Addition Cascades And Extension To Chiral Auxiliary-Based Variants, Chunyin Marshall Law

Theses and Dissertations

Oxidopyrylium-based [5+2] cycloadditions have been extensively utilized to construct oxabridged seven-membered ring systems that often serve as the core structures in numerous biologically active natural products. By investigating these processes, we hope to reveal the highest potentials of [5+2] cycloaddition as a synthetic tool.

A novel oxidopyrylium-alkene [5+2] cycloaddition conjugate addition cascade (C3) sequence, which allows rapid build-up of molecular complexity with excellent diastereocontrol, was investigated. The scope and limitation of this process were explored as mixed results were shown for various acetoxypyranone-alkene substrates. In addition, oxidopyrylium [5+2] cycloadditions of ï?¢-silyloxy-ï?§-pyrones were investigated which revealed the accelerating role of carbonyl …


Applications Of Organic Probes For Imaging And Analysis Of Different Cancer Cell Models, Hong Guan May 2015

Applications Of Organic Probes For Imaging And Analysis Of Different Cancer Cell Models, Hong Guan

Theses and Dissertations

Novel techniques for better studying cancer cell behavior and progression are extremely important. Our lab is interested in synthesizing specifically designed organic reagents and applying them in the studies of cancers. In this dissertation, we used organic probes to investigate cancer cells in the following topics: determination of amino acid concentration in different types of cancers, tumor toxicity of organic probes towards HER2 positive breast cancer cells, glycoproteins identification in breast cancer cells and development of enzyme activity assay for colon cancer cells.

The first chapter was focused on the determination of cysteine/homocysteine concentrations using turn-on sensors in cancer cells. …


Impact Of Ocean Acidification On Aphotic Biogeochemical Production Of Reactive Oxygen Species, Sarah Ann Murphy May 2015

Impact Of Ocean Acidification On Aphotic Biogeochemical Production Of Reactive Oxygen Species, Sarah Ann Murphy

Theses and Dissertations

Reactive oxygen species (ROS) are critical to global maintenance of the global organic carbon cycle, sulfur cycle, oxygen cycle, and transition metal cycles. The primary source of ROS is commonly considered to be photolysis or photochemically driven reactions, however ROS also exist in aphotic zones. A geochemical mechanism for the same in dark environments based on the tidally driven, episodic movement of anoxic groundwaters through oxidized, Fe(III) rich sediments is shown. Predictive models were developed based on in vitro experiments and tested using sediment samples collected from a saline tidal creek in the estuary at Murrell’s Inlet, South Carolina. These …