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First-Principles Investigation Of The Interfacial Properties Of Boron Nitride, Kevin Waters Jan 2018

First-Principles Investigation Of The Interfacial Properties Of Boron Nitride, Kevin Waters

Dissertations, Master's Theses and Master's Reports

The interactions of nanomaterial surfaces with biological compounds, e.g. proteins, DNA, etc., unites the biological regime and nanomaterial world. Hybrid systems of boron-nitride nanotubes (BNNTs) and biological compounds are well-suited for a broad range of applications. First-principles methods are used to characterize the interface of these hybrid systems. Previous work has shown that the sensing capabilities of pristine BNNT are limited by long-ranged interactions. In this study the surfaces of pristine and functionalized BNNTs are investigated. The surfaces of the functionalized BNNTs give new properties to the tubes, which may enhance their sensing capabilities, while retaining their stability and chemical …


Synthesis Of Heterocycles Through Beta Lactams Ring Rupture, Bimal K. Banik Jan 2018

Synthesis Of Heterocycles Through Beta Lactams Ring Rupture, Bimal K. Banik

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

Many Beta lactams are widely used as medicines. The 4-membered ring present in the beta lactams is under strain and therefore, it can undergo cleavage reactions to diverse compounds. Chemical manipulation of the resulting products affords numerous molecules of interest. In this perspective, some examples developed at our laboratory are discussed


Versatile Catalytic Transfer Hydrogenations In Organic Synthesis, Bimal K. Banik, Khaled J. Barakat, Maghar S. Manhas Jan 2018

Versatile Catalytic Transfer Hydrogenations In Organic Synthesis, Bimal K. Banik, Khaled J. Barakat, Maghar S. Manhas

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

Catalytic transfer hydrogenation reactions are extremely useful in organic synthesis. We have investigated numerous reactions with ammonium formate (and other hydrogen gas donor) and 10% Pd/C successfully without using hydrogen gas. The reactions are very fast and produced products with high yields. Reduction of unsaturated groups, hydrogenolysis, reductive bond cleavage, allylic deacetoxylation, and dehalogenation are conducted using this method. In some instances, useful selectivity of reactions is observed. Most of the reactions are investigated with β-lactams as the substrates.


Stereoselectivity Of Phthalimido Β-Lactams Formation: Synthesis Of 3-Amino Β-Lactams Through A Facile Deprotection Reaction, Armando Paniagua, Ram Naresh Yadav, Sunena Chandra, Bimal K. Banik Jan 2018

Stereoselectivity Of Phthalimido Β-Lactams Formation: Synthesis Of 3-Amino Β-Lactams Through A Facile Deprotection Reaction, Armando Paniagua, Ram Naresh Yadav, Sunena Chandra, Bimal K. Banik

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

Synthesis of amino β-lactams is a crucial objective because of the medicinal properties associated with them and the products derived from of them. Stereocontrolled synthesis of phthalimido β-lactams is performed and cis and trans-phthalimido β-lactams are deprotected with ethylene diamine (and other reagents) to amino β-lactams of diverse structures in excellent yield. This reaction is also conducted under solventless conditions to afford identical products.


Emerging Infectious Disease And The Imperiled Relict Leopard Frog, Anthony Wayne Waddle Dec 2017

Emerging Infectious Disease And The Imperiled Relict Leopard Frog, Anthony Wayne Waddle

UNLV Theses, Dissertations, Professional Papers, and Capstones

The disease chytridiomycosis, caused by the aquatic fungal pathogen Batrachochytrium dendrobatidis (Bd), has emerged as a major contributing factor for worldwide amphibian declines. Although relatively recently described, the impacts from the disease this pathogen causes have been definitively tied to amphibian declines, including some that occurred decades ago. In some cases, declines of individual species occurred with little documentation and are thus poorly understood. The relict leopard frog (Rana onca = Lithobates onca) has experienced such a decline and by the latter part of the 20th century only occurred in two general areas in southern Nevada. Recent research has found …


Metastable-State Nh Photoacids And Organic Photo Carbon Monoxide Releasing Materials, Aluthwatte Rallage Nawodi Madhusanka Abeyrathna Dec 2017

Metastable-State Nh Photoacids And Organic Photo Carbon Monoxide Releasing Materials, Aluthwatte Rallage Nawodi Madhusanka Abeyrathna

Theses and Dissertations

The recently discovered metastable-state photoacids (mPAHs) can produce a large proton concentration with high efficiency and good reversibility upon irradiation with visible light with moderate intensity. Therefore, mPAHs can be conveniently incorporated in to different systems to control various proton-transfer processes. Recently, several applications of mPAHs have been demonstrated. However, none of the previously reported mPAHs can function at a pH 7.4. Thus, biological applications of mPAHs are limited. In this work, mPAHs that can reversibly release a proton in PBS buffer (pH = 7.4) under visible light are designed and synthesized. NH-PAH-1 is the first of this type of …


Two-Photon Excitation, Fluorescence Microscopy, And Quantitative Measurement Of Two-Photon Absorption Cross Sections, Fredrick Michael Dearmond Dec 2017

Two-Photon Excitation, Fluorescence Microscopy, And Quantitative Measurement Of Two-Photon Absorption Cross Sections, Fredrick Michael Dearmond

Dissertations and Theses

As optical microscopy techniques continue to improve, most notably the development of super-resolution optical microscopy which garnered the Nobel Prize in Chemistry in 2014, renewed emphasis has been placed on the development and use of fluorescence microscopy techniques. Of particular note is a renewed interest in multiphoton excitation due to a number of inherent properties of the technique including simplified optical filtering, increased sample penetration, and inherently confocal operation. With this renewed interest in multiphoton fluorescence microscopy, comes an increased demand for robust non-linear fluorescent markers, and characterization of the associated tool set.

These factors have led to an experimental …


Phosphoproteomics Profiling Of Nonsmall Cell Lung Cancer Cells Treated With A Novel Phosphatase Activator, Danica Wiredja, Marzieh Ayati, Sahar Mazhar, Jaya Sangodkar, Sean Maxwell, Daniela Schlatzer, Goutham Narla, Mehmet Koyutürk, Mark R. Chance Nov 2017

Phosphoproteomics Profiling Of Nonsmall Cell Lung Cancer Cells Treated With A Novel Phosphatase Activator, Danica Wiredja, Marzieh Ayati, Sahar Mazhar, Jaya Sangodkar, Sean Maxwell, Daniela Schlatzer, Goutham Narla, Mehmet Koyutürk, Mark R. Chance

Computer Science Faculty Publications

Activation of protein phosphatase 2A (PP2A) is a promising anti-cancer therapeutic strategy, as this tumor suppressor has the ability to coordinately downregulate multiple pathways involved in the regulation of cellular growth and proliferation. In order to understand the systems-level perturbations mediated by PP2A activation, we carried out mass spectrometry-based phosphoproteomic analysis of two KRAS mutated non-small cell lung cancer (NSCLC) cell lines (A549 and H358) treated with a novel Small Molecule Activator of PP2A (SMAP). Overall, this permitted quantification of differential signaling across over 1,600 phosphoproteins and 3,000 phosphosites. Kinase activity assessment and pathway enrichment implicated collective downregulation of RAS …


Synthesis, Characterization And Application Of Sugar-Based Low Molecular Weight Gelators, Ifeanyi Simeon Okafor Oct 2017

Synthesis, Characterization And Application Of Sugar-Based Low Molecular Weight Gelators, Ifeanyi Simeon Okafor

Chemistry & Biochemistry Theses & Dissertations

Low molecular weight gelators (LMWGs) are an interesting class of compound that have gained considerable attention especially because of their potential applications for soft biomaterials. Carbohydrate based low molecular weight hydrogelators and organogelators are able to selfassemble and form ordered supramolecular structures, which are useful for exploring biomedical applications. The resulting gelators are responsive to external stimuli because of the weak noncovalent intermolecular forces and interaction that influences self-assembly. Stimuli-responsive supramolecular organogels with interesting properties in response to external environmental stimuli have gained considerable attention due to their applications in biomaterials, sensors and for drug delivery.

One of the major …


Toxicant Formation In Dabbing: The Terpene Story, Jiries Meehan-Attrash, Wentai Luo, Robert M. Strongin Sep 2017

Toxicant Formation In Dabbing: The Terpene Story, Jiries Meehan-Attrash, Wentai Luo, Robert M. Strongin

Chemistry Faculty Publications and Presentations

Inhalable, noncombustible cannabis products are playing a central role in the expansion of the medical and recreational use of cannabis. In particular, the practice of “dabbing” with butane hash oil has emerged with great popularity in states that have legalized cannabis. Despite their growing popularity, the degradation product profiles of these new products have not been extensively investigated. The study herein focuses on the chemistry of myrcene and other common terpenes found in cannabis extracts. Methacrolein, benzene, and several other products of concern to human health were formed under the conditions that simulated realworld dabbing. The terpene degradation products observed …


Heterogeneity Aware Random Forest For Drug Sensitivity Prediction, Raziur Rahman, Kevin Matlock, Souparno Ghosh, Ranadip Pal Sep 2017

Heterogeneity Aware Random Forest For Drug Sensitivity Prediction, Raziur Rahman, Kevin Matlock, Souparno Ghosh, Ranadip Pal

Department of Statistics: Faculty Publications

Samples collected in pharmacogenomics databases typically belong to various cancer types. For designing a drug sensitivity predictive model from such a database, a natural question arises whether a model trained on diverse inter-tumor heterogeneous samples will perform similar to a predictive model that takes into consideration the heterogeneity of the samples in model training and prediction. We explore this hypothesis and observe that ensemble model predictions obtained when cancer type is known out-perform predictions when that information is withheld even when the samples sizes for the former is considerably lower than the combined sample size. To incorporate the heterogeneity idea …


Synthesis Of Small Molecule Heterocycles As Antimicrobial And Anticancer Agents, Zakeyah Ali Alsharif Sep 2017

Synthesis Of Small Molecule Heterocycles As Antimicrobial And Anticancer Agents, Zakeyah Ali Alsharif

Student Theses and Dissertations

This thesis contains three chapters. In chapter one, the synthesis of dihydropyrido-pyrimidones derivatives by using hexafluoroisopropanol (HFIP) as a solvent was reported and the synthesized compounds were tested against different bacteria but no activity was observed. In the second chapter, the syntheses of thiazoline and thiazole derivatives were reported. In this methodology, HFIP was used to promote for the reaction and sixty new molecules were synthesized. Two of these compounds showed promising activity as a potent anti-cancer agent against several cell lines. In the third chapter, pyrazole derivatives were synthesized and tested against different types of bacteria. Among these compounds, …


Genetic And Biological Studies On Solanum Plants: Insights Into The Leaf Wax Alkane Paleoclimate Proxy, Amanda Lorraine Dorothy Bender Aug 2017

Genetic And Biological Studies On Solanum Plants: Insights Into The Leaf Wax Alkane Paleoclimate Proxy, Amanda Lorraine Dorothy Bender

Arts & Sciences Graduate Student Theses and Dissertations

The hydrogen isotopic composition (δ2H) of precipitation records fluxes of water in the hydrological cycle, and can reflect climatic variables such as temperature and humidity. Leaf wax n-alkanes can record δ2H of precipitation; consequently, n-alkanes extracted from sedimentary archives are commonly used as proxies for paleoenvironmental reconstruction. However, the utility of the leaf wax paleoclimate proxy is modulated by uncertainty about how physiological processes affect hydrogen isotopic compositions during alkane biosynthesis. This work aims to improve our understanding of the leaf wax paleoclimate proxy by examining biological and environmental sources of variability on cuticular leaf waxes. We used Solanum (tomato) …


Review: New Frontiers In Metabolomics: From Measurement To Insight, Eli Riekeberg, Robert Powers Jul 2017

Review: New Frontiers In Metabolomics: From Measurement To Insight, Eli Riekeberg, Robert Powers

Robert Powers Publications

Metabolomics is the newest addition to the “omics” disciplines and has shown rapid growth in its application to human health research because of fundamental advancements in measurement and analysis techniques. Metabolomics has unique and proven advantages in systems biology and biomarker discovery. The next generation of analysis techniques promises even richer and more complete analysis capabilities that will enable earlier clinical diagnosis, drug refinement, and personalized medicine. A review of current advancements in methodologies and statistical analysis that are enhancing and improving the performance of metabolomics is presented along with highlights of some recent successful applications.


Design And Synthesis Of Selective Estrogen Receptor Β Agonists And Their Pharmacology, K. L. Iresha Sampathi Perera Jul 2017

Design And Synthesis Of Selective Estrogen Receptor Β Agonists And Their Pharmacology, K. L. Iresha Sampathi Perera

Dissertations (1934 -)

Estrogens (17β-estradiol, E2) have garnered considerable attention in influencing cognitive process in relation to phases of the menstrual cycle, aging and menopausal symptoms. However, hormone replacement therapy can have deleterious effects leading to breast and endometrial cancer, predominantly mediated by estrogen receptor-alpha (ERα) the major isoform present in the mammary gland and uterus. Further evidence supports a dominant role of estrogen receptor-beta (ERβ) for improved cognitive effects such as enhanced hippocampal signaling and memory consolidation via estrogen activated signaling cascades. Creation of the ERβ selective ligands is challenging due to high structural similarity of both receptors. Thus far, several ERβ …


Lichen Conservation In Eastern North America: Population Genomics, Climate Change, And Translocations, Jessica Allen Jun 2017

Lichen Conservation In Eastern North America: Population Genomics, Climate Change, And Translocations, Jessica Allen

Dissertations, Theses, and Capstone Projects

Conservation biology is a scientific discipline that draws on methods from diverse fields to address specific conservation concerns and inform conservation actions. This field is overwhelmingly focused on charismatic animals and vascular plants, often ignoring other diverse and ecologically important groups. This trend is slowly changing in some ways; for example, increasing number of fungal species are being added to the IUCN Red-List. However, a strong taxonomic bias still exists. Here I contribute four research chapters to further the conservation of lichens, one group of frequently overlooked organisms. I address specific conservation concerns in eastern North America using modern methods. …


Novel Spectroscopic Tools To Differentiate Drug-Dna Binding Interactions, Fadwa Dhafer Hamad Jun 2017

Novel Spectroscopic Tools To Differentiate Drug-Dna Binding Interactions, Fadwa Dhafer Hamad

Masters Theses

DNA-drug interactions play a major role in therapeutics, diagnostics, forensics and imaging. Drugs bind to DNA in several ways based on the mode of interaction and they alter protein-DNA interactions or breaks/cleaves DNA that can lead to the cure of the disease. The major goal of the research carried out in this thesis is to develop novel optical spectroscopic tools that can differentiate Drug-DNA binding interactions mode whether its intercalation or minor-groove binding. To achieve this goal, we developed two-photon absorption (2PA) cross-section based technique to differentiate between Drug-DNA binding modes. The investigations were carried out on two drug molecules, …


Some Contributions To The Analysis Of Dual-Record System For Estimating Human Population Size., Kiranmoy Chatterjee Dr. May 2017

Some Contributions To The Analysis Of Dual-Record System For Estimating Human Population Size., Kiranmoy Chatterjee Dr.

Doctoral Theses

Dual-record System (DRS) The problem of population size estimation is a very important administrative and statistical concern which includes a vast area of application in the fields of epidemiology, demography and official statistics. Federal agencies are generally interested to know the actual size (say, N ) of a specified population or any vital event that occurred in a specified area within a given time span. Census or civil registration system often fails to extract the true size of the population. The degree of inaccuracy depends on the actual size of the population, its diversity and of course, on the quality …


Stereochemical Preference Toward Oncotarget: Design Synthesis And In Vitro Anticancer Evaluation Of Diastereomeric B-Lactams, Fabian Olazarán-Santibáñez, Debasish Bandyopadhyay, Pilar Carranza-Rosales, Gildardo Rivera, Isias Balderas-Rentería May 2017

Stereochemical Preference Toward Oncotarget: Design Synthesis And In Vitro Anticancer Evaluation Of Diastereomeric B-Lactams, Fabian Olazarán-Santibáñez, Debasish Bandyopadhyay, Pilar Carranza-Rosales, Gildardo Rivera, Isias Balderas-Rentería

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

Purpose: In the battle against cancer discovery of new and novel chemotherapeutic agent demands extreme obligation. Development of anticancer compounds with higher potency and reduced side-effects is timely and challenging.

Experimental Design: A small series of fourteen diastereomeric β-lactams (seven pairs) were synthesized through multi-step process exploring [2+2] ketene-imine cycloaddition as the key step. Comparative stereochemical preferences were studied through computational docking and validated by in vitro evaluation. β-tubulin was considered as possible molecular target and in vitro anticancer evaluation was conducted against SiHa, B16F10, K562 and Chang cell lines. Caspase-3 activation assay and hematoxylin/eosin staining of the cells were …


Elemental Contamination Of An Ancient Copper Mine In Killarney, Ireland, Courtney Chouinard May 2017

Elemental Contamination Of An Ancient Copper Mine In Killarney, Ireland, Courtney Chouinard

Celebration of Learning

Ross Island Copper Mine, located in Killarney National Park, Killarney, Ireland, is known for archeological artifacts of copper from the Bronze Age. Copper production surged in the late 1700s and into the mid-1800s. The mine included both open pits (e.g. Blue Hole) and underground excavations (e.g. Western Mine). Copper veins were found in the Mississippian-aged limestone bedrock along with chalcopyrite and tennantite ore. In 1912, tourism had become the main source of income in the area, and the mines and the land surrounding them were remediated and became a part of the national park. Mine shafts were filled in, waste …


Development Of New Routes For The Synthesis Of Carbaporphyrins And Carbachlorins, Navneet Sahota May 2017

Development Of New Routes For The Synthesis Of Carbaporphyrins And Carbachlorins, Navneet Sahota

Theses and Dissertations

Carbaporphyrins and carbachlorins are porphyrin analogs in which one of the nitrogens is replaced with a carbon atom within a porphyrin-like cavity. These systems form stable organometallic derivatives and exhibit unusual chemical reactivity. In the monocarbaporphyrinoids such as benzocarbaporphyrins, one of the pyrrole rings is replaced by an indene unit. Although syntheses of monocarbaporphyrins with fused rings have been widely investigated over the past 20 years, a few examples of carbaporphyrins without fused rings have been reported in the literature.

In this thesis, two projects were conducted to further explore carbaporphyrin and carbachlorin chemistry. The first project utilized a ‘3+1’ …


Chaos To Permanence - Through Control Theory, Sherli Koshy Chenthittayil May 2017

Chaos To Permanence - Through Control Theory, Sherli Koshy Chenthittayil

All Dissertations

Work by Cushing et al. [18] and Kot et al. [60] demonstrate that chaotic behavior does occur in biological systems. We demonstrate that chaotic behavior can enable the survival/thriving of the species involved in a system. We adopt the concepts of persistence/permanence as measures of survival/thriving of the species [35]. We utilize present chaotic behavior and a control algorithm based on [66, 72] to push a non-permanent system into permanence. The algorithm uses the chaotic orbits present in the system to obtain the desired state. We apply the algorithm to a Lotka-Volterra type two-prey, one-predator model from [30], a ratio-dependent …


Synthesis, Characterization And Biological Studies Of Technetium-99m And Rhenium-188 Peptides, Vanessa Anne Sanders May 2017

Synthesis, Characterization And Biological Studies Of Technetium-99m And Rhenium-188 Peptides, Vanessa Anne Sanders

UNLV Theses, Dissertations, Professional Papers, and Capstones

Radiopharmaceuticals are very powerful diagnostic tools for evaluation of a host of medical conditions. These drugs are labeled with radioactive isotopes, which are utilized to create pictures of areas of interest through absorption of the drug. They are currently in high demand due to their ability to image areas that traditional imaging devices cannot. The radioisotope 99mTc, with a half-life of 6.01 hours and a 140 keV gamma emission, is central to many radiopharmaceutical compounds. This isotope is easily obtained from a 99Mo-99mTc generator, through beta decay and column chromatography separations. Very little technetium, less than 6 ng, is needed …


Network Exploration Of Correlated Multivariate Protein Data For Alzheimer's Disease Association, Matthew J. Lane Apr 2017

Network Exploration Of Correlated Multivariate Protein Data For Alzheimer's Disease Association, Matthew J. Lane

Theses

Alzheimer Disease (AD) is difficult to diagnose by using genetic testing or other traditional methods. Unlike diseases with simple genetic risk components, there exists no single marker determining as to whether someone will develop AD. Furthermore, AD is highly heterogeneous and different subgroups of individuals develop the disease due to differing factors. Traditional diagnostic methods using perceivable cognitive deficiencies are often too little too late due to the brain having suffered damage from decades of disease progression. In order to observe AD at early stages prior to the observation of cognitive deficiencies, biomarkers with greater accuracy are required. By using …


Conformational Studies Of A Domain Of The Influenza A M2 Protein Involved In Viral Budding And Morphology, Alice L. Herneisen , '17 Apr 2017

Conformational Studies Of A Domain Of The Influenza A M2 Protein Involved In Viral Budding And Morphology, Alice L. Herneisen , '17

Senior Theses, Projects, and Awards

In my two years working in the Howard lab, I have cycled through a number of projects. These projects fall under the broad context of studying of how the cytoplasmic tail of a particular membrane protein of the influenza A virus, the Matrix protein 2 (M2), is involved in viral budding. I have chosen to present each project in the form of an independent manuscript, with separate Introduction, Experimental, Results, and Discussion sections. Some broader background and theory is briefly provided in Chapters 1 and 2, but Chapters 3-5 are designed to be largely self-contained. Potential future directions pertaining to …


Scalable Unsupervised Learning With Game Theory, Alireza Chakeri Mar 2017

Scalable Unsupervised Learning With Game Theory, Alireza Chakeri

USF Tampa Graduate Theses and Dissertations

Recently dominant sets, a generalization of the notion of the maximal clique to edge-weighted graphs, have proven to be an effective tool for unsupervised learning and have found applications in different domains. Although, they were initially established using optimization and graph theory concepts, recent work has shown fascinating connections with evolutionary game theory, that leads to the clustering game framework. However, considering size of today's data sets, existing methods need to be modified in order to handle massive data. Hence, in this research work, first we address the limitations of the clustering game framework for large data sets theoretically. We …


Abundance And Habitat Preferences Of Introduced Muscovy Ducks (Cairina Moschata), Jacqueline Marie Perry Cahanin Mar 2017

Abundance And Habitat Preferences Of Introduced Muscovy Ducks (Cairina Moschata), Jacqueline Marie Perry Cahanin

USF Tampa Graduate Theses and Dissertations

Muscovy ducks are native only to Central and South America, Mexico, and parts of southern Texas and are considered invasive in some areas outside of their native range. Although they have been introduced worldwide, they remain largely unstudied. The primary focus of this study was to relate Muscovy duck abundance to habitat characteristics of wetlands in Tampa, Florida. Muscovy abundance was measured using point count methods at 21 wetland sites that occur within an eight km radius of the University of South Florida’s main campus. Habitat features at these sites were assessed using field methods and Geographic Information Systems (GIS) …


Designing Proteins For Biomechanical And Molecular Biological Studies, Momoko Tajiri Mar 2017

Designing Proteins For Biomechanical And Molecular Biological Studies, Momoko Tajiri

TechTalks

Proteins are large biomolecules consisting one or more long chain of amino acid residues. Proteins perform a wide variety of functions within organisms including catalyzing metabolic activities, signal transduction, and transportation of molecules. They function differently from one another as their sequences of amino acids and also due to a variation of modification placed on residues. Change in modification patterns will impact protein interaction with other molecules, thus influence normal cell activities and may lead to disease development. In order to study the consequences of modification, we have a method to prepare proteins with desired modification patterns. Using the technique, …


Sulfur Isotope Characteristics Of The Permian Vhms Deposits In Tasik Chini District, Central Belt Of Peninsular Malaysia, Mohd Basril Iswadi Basori, Khin Zaw, Robert Ross Large, Wan Fuad Wan Hassan Jan 2017

Sulfur Isotope Characteristics Of The Permian Vhms Deposits In Tasik Chini District, Central Belt Of Peninsular Malaysia, Mohd Basril Iswadi Basori, Khin Zaw, Robert Ross Large, Wan Fuad Wan Hassan

Turkish Journal of Earth Sciences

Sulfur isotope data from sulfide and sulfate minerals have been measured from the two typical examples of the Permian volcanic-hosted massive sulfide (VHMS) deposits at the Tasik Chini district in the Central Belt of Peninsular Malaysia. In this study, we present the sulfur isotope data for 33 sulfide minerals and 23 barite samples from two VHMS deposits in the Tasik Chini district. Sulfides show a narrow range of sulfur values from -2.9%o to +8.30%o, which can be interpreted to be derived from a mixed sulfur source of reduced seawater sulfate with the possible addition of magmatic sulfur. Sulfate sulfur in …


Synthesis And Reactivity Of Sydnone Derived 1,3,4-Oxadiazol-2(3h)-Ones, Jonathan Michael Tumey Jan 2017

Synthesis And Reactivity Of Sydnone Derived 1,3,4-Oxadiazol-2(3h)-Ones, Jonathan Michael Tumey

Browse all Theses and Dissertations

5-(Bromomethyl)- and 5-(trichloromethyl)-3-phenyl-1,3,4-oxadiazol-2(3H)-ones were synthesized from bromocarbonyl hydrazine intermediate salts and acid halides to provide further evidence for our proposed mechanism for the formation of oxadiazolone ring systems from sydnones. 5-(Bromomethyl)-3-phenyl-1,3,4-oxadiazol-2(3H)-one was a compound of interest due to its SN2 possibilities and three potential sites of diversification. The procedure to synthesize 5-(bromomethyl)-3-phenyl-1,3,4-oxadiazol-2(3H)-one was developed originally by Madaram in the Turnbull lab, but was further optimized in the present work by altering the time, temperature and stoichiometric equivalents of the acid halide to provide high purity and excellent yields of the product. While this compound of interest had been isolated and …