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Preparation And Derivatization Of Novel Sydnonimines And Their Esters, Timothy Luke Teschler Jan 2007

Preparation And Derivatization Of Novel Sydnonimines And Their Esters, Timothy Luke Teschler

Browse all Theses and Dissertations

Some years ago, we reported that 3-phenylsydnone underwent dilithiation to yield the dilithio species, upon treatment with n-butyllithium. Subsequent reactions with electrophiles led to variously substituted aryl sydnones, dependent on the nature of the electrophile employed. Sydnonimines, exocyclic nitrogen analogs of sydnones, exhibit interesting biological properties and, accordingly, it was of value to explore whether or not the dilithiation approach could be extended to such species. In the present work a series of N-6-ethoxycarbonyl-3-arylsydnonimines were synthesized from the corresponding sydnonimine hydrochlorides in moderate yields (22-77%). Attempted dilithiations of N-6-ethoxycarbonyl-3-arylsydnonimines and trapping with iodine proved to be problematic, yielding only the …

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Fabrication Of Dna Microarrays On Poly (Methylmethacrylate) Substrates For Biomolecular Reporting, Catherine N. Situma Jan 2007

Fabrication Of Dna Microarrays On Poly (Methylmethacrylate) Substrates For Biomolecular Reporting, Catherine N. Situma

LSU Doctoral Dissertations

DNA microarrays require the use of substrates with well-established surface modification / probe attachment chemistries. Glass/quartz have been widely adopted as typical support materials since their surface modification chemistries which involve the use of siloxane –based chemistries have been widely studied however; these chemistry is susceptible to hydrolytic cleavage especially at high or low pH values. Recently, polymers have been sought as alternative microarray support materials but their surface modification strategies are not well characterized compared to glass. This report will entail surface photo-modification of PMMA polymer substrates by UV irradiation which produces functional scaffolds of carboxylic groups that allow …

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Hadron Models And Related New Energy Issues, Florentin Smarandache Jan 2007

Hadron Models And Related New Energy Issues, Florentin Smarandache

Branch Mathematics and Statistics Faculty and Staff Publications

The present book covers a wide-range of issues from alternative hadron models to their likely implications in New Energy research, including alternative interpretation of lowenergy reaction (coldfusion) phenomena. The authors explored some new approaches to describe novel phenomena in particle physics. M Pitkanen introduces his nuclear string hypothesis derived from his Topological Geometrodynamics theory, while E. Goldfain discusses a number of nonlinear dynamics methods, including bifurcation, pattern formation (complex GinzburgLandau equation) to describe elementary particle masses. Fu Yuhua discusses a plausible method for prediction of phenomena related to New Energy development. F. Smarandache discusses his unmatter hypothesis, and A. Yefremov …

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In Vivo Imaging Of Transport And Biocompatibility Of Single Silver Nanoparticles In Early Development Of Zebrafish Embryos, Kerry J. Lee, Prakash D. Nallathamby, Lauren M. Browning, Christopher J. Osgood, Xiao-Hong Nancy Xu Jan 2007

In Vivo Imaging Of Transport And Biocompatibility Of Single Silver Nanoparticles In Early Development Of Zebrafish Embryos, Kerry J. Lee, Prakash D. Nallathamby, Lauren M. Browning, Christopher J. Osgood, Xiao-Hong Nancy Xu

Chemistry & Biochemistry Faculty Publications

Real-time study of the transport and biocompatibility of nanomaterials in early embryonic development at single-nanoparticle resolution can offer new knowledge about the delivery and effects of nanomaterials in vivo, and provide new insights into molecular transport mechanisms in developing embryos. In this study, we directly characterized the transport of single silver nanoparticles into an in vivo model system (zebrafish embryos) and investigated their effects on early embryonic development at single-nanoparticle resolution in real time. We designed highly purified and stable (not aggregated and no photodecomposition) nanoparticles and developed single-nanoparticle optics and in vivo assays to enable the study. We …

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Synthesis And Solid State F-Nmr Studies On Fluorine-Labeled Antimicrobial Peptide Rk-21, Mahender Budarapu Jan 2007

Synthesis And Solid State F-Nmr Studies On Fluorine-Labeled Antimicrobial Peptide Rk-21, Mahender Budarapu

Master's Theses and Doctoral Dissertations

Antimicrobial peptides act against bacteria by binding non-specifically and disrupting their outer membrane. LL-37 is the only member of the cathelicidin group of antimicrobial peptides present in humans and shows a broad range of antimicrobial activity. RK-21 is a fragment of human antimicrobial peptide LL-37, which is α-helical, cationic and amphipathic in nature. RK-21 displays similar antimicrobial activity to LL- 37. In order to understand the mechanism of lipid bilayer disruption, fluorine-labeled antimicrobial peptide RK-21 was chemically synthesized and 19F-NMR studies were done. NMR studies were done at various peptide concentrations, on different lipid bilayer compositions and temperatures. 31P-NMR studies …

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Characterization Of A Black Coating Overlying Rock Paintings Found In Little Lost River Cave, Idaho Using Thm-Gc-Ms, Jamie Brown-Sinha Jan 2007

Characterization Of A Black Coating Overlying Rock Paintings Found In Little Lost River Cave, Idaho Using Thm-Gc-Ms, Jamie Brown-Sinha

Master's Theses and Doctoral Dissertations

A black coating overlies rock paintings found within Little Lost Rive Cave, Idaho. A calibrated radiocarbon date of 1390-1040 B.C. was obtained by Steelman et al.1 However, this relies on the assumption that the black coating was formed by some human activity. For further characterization and to verify that the coating is anthropogenic, THM-GC-MS was performed on various samples collected throughout the cave, including soil samples from inside, outside, and above the cave. Humic and fulvic acids, synthetic and natural melanin, and experimentally created cooking residues were also analyzed as standard materials. By comparing the resulting chromatograms and the compounds …

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The Electroanalytical Performance Of Sonogel Carbon Titanium (Iv) Oxide Electrodes Versus Conducting Polymer Electrodes In The Electrochemical Detection Of Biological Molecules, Jelynn A. Stinson Jan 2007

The Electroanalytical Performance Of Sonogel Carbon Titanium (Iv) Oxide Electrodes Versus Conducting Polymer Electrodes In The Electrochemical Detection Of Biological Molecules, Jelynn A. Stinson

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The electrochemical performance of a newly developed sonogel carbon titanium (IV) oxide (SGC/TiO2 ) electrode against poly(3-methylthiophene) (P3MT) and poly(2,2'-bithiophene) (PBTP) modified electrodes in the electrochemical detection of biological molecules is reported. The stability of the Titanium (IV) Oxide coating on the sonogel carbon electrode was shown to be greater than the P3MT coating on the conventional size glassy carbon electrode. After 10 consecutive scans, there was a 21% loss of the initial signal at the P3MT modified electrode and a 5% loss of the initial signal at the SGC/TiO2 electrode. The influence of NAD+ on NADH response was tested. …

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Solution Conformations Of Three Small Cluster Oligosaccharide Mimetics (Scom) From D-Glucosamine, D-Altrosamine, And (-)-Quinic Acid, Q. L. Nguyen, L. Olmstead, S. Bains, Andreas H. Franz Jan 2007

Solution Conformations Of Three Small Cluster Oligosaccharide Mimetics (Scom) From D-Glucosamine, D-Altrosamine, And (-)-Quinic Acid, Q. L. Nguyen, L. Olmstead, S. Bains, Andreas H. Franz

College of the Pacific Faculty Articles

Three small cluster oligosaccharide mimetics were synthesized, and their CDCl3 solution conformations were determined with NMR experiments. In this paper, we confirmed conformational similarities in rings A and B in all three compounds, and we provide the overall solution geometries. In all cases, an unusual cyclohexane twist-boat conformation with longrange 4 J-(W)-coupling was observed. The origin of the bias towards the twist-boat was attributed primarily to the fused ring system between the cyclohexane ring and the dioxacyclopentane (acetal) including hydrogen bonding. Temperature-annealed molecular dynamics simulations complemented the NMR experiments and supported the overall assignment.

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Synthetic Approach To Epibatidine From 1-(Phenylsulfonyl)Pyrrole, Brandon G. Vanness Jan 2007

Synthetic Approach To Epibatidine From 1-(Phenylsulfonyl)Pyrrole, Brandon G. Vanness

Browse all Theses and Dissertations

The goal of this research was to synthesize the natural product epibatidine, a non-opiate analgesic and nicotinic acetylcholine agonist isolated from Epipedobates tricolor. A synthetic pathway utilizing a Diels-Alder cycloaddition of a 3-pyridyl substituted pyrrole and tosylacetylene was conceived based upon the original mass spectral fragmentation pathway of epibatidine determined by Daly. Although this pathway had been previously attempted using 1-(triisopropyl)-3-[5-(2-chloropyridyl)]pyrrole in the key Diels-Alder step, the lack of cycloadduct suggested that a pyrrole with a more electron withdrawing protecting group was required for this step. Therefore, synthesis of 1-(phenylsulfonyl)-3-[5-(2-chloropyridyl)]pyrrole via a palladium catalyzed cross-coupling reaction of 1-(phenylsulfonyl)-3-pyrroline and …

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Synthetic Routes To A Fused-Ring Sydnoquinazoline, Gregory Edmond Storer Jan 2007

Synthetic Routes To A Fused-Ring Sydnoquinazoline, Gregory Edmond Storer

Browse all Theses and Dissertations

In this research, 5-methylsydno-[3,4-a]quinazoline was synthesized via multiple methodologies, the best of which yielded the target compound in 50 % overall yield for the six steps. Synthesis of this compound in reasonable yields and exploration of its chemical behavior is of particular interest as a putative NO-prodrug. As an initial approach to the synthesis and accumulation of the compound of interest, attempts were made to optimize the existing synthetic pathway to its precursors. The starting material, 3-(2-acetylphenyl)sydnone, was prepared in 3 steps from commercially available starting material in good yields. This sydnone compound was then converted to the versatile intermediate, …

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Modifiable Poly(Arylene Ether)S And Hyperbranched Poly(Esters), Brian Scott Werry Jan 2007

Modifiable Poly(Arylene Ether)S And Hyperbranched Poly(Esters), Brian Scott Werry

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Two different polymer systems have been studied in regards to their potential for functionalization to introduce new characteristics to the polymer. The first polymer system is a poly(arylene ether) with a truly pendant sulfone group from the monomer 3,5-difluorodiphenylsulfone. The work entails incorporating a bromine moiety onto the monomer for the versatile ability to bring in functional groups prior to or post the polymerization. The introduction of bromine onto the pendant ring had the best results from electrophilic bromine addition using N-bromosuccinimide in a mixture of sulfuric acid and acetic acid (80:20) yielding 76% of the desired material. Incorporation of …

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Simple Descriptors For Modeling The Solubility Of Gases, Alcohols, And Halogenated Hydrocarbons In Water, Sule Sidigu Jan 2007

Simple Descriptors For Modeling The Solubility Of Gases, Alcohols, And Halogenated Hydrocarbons In Water, Sule Sidigu

Browse all Theses and Dissertations

The Statmost, QSARIS, Excel, and SAS programs were used to model the solubility of gases, alcohols, and halogenated hydrocarbons in water using simple physical and topological descriptors. The alcohols were well-modeled using measures of the number of carbons, terminal methyls, and steric hindrance about the hydroxyl group. Molecular mass, boiling point, and critical volume or critical pressure were the best descriptors for the halogenated hydrocarbons. Critical pressure was the most applicable single descriptor for the gases. Molecular mass and boiling point also yielded good results for the gases and halogenated hydrocarbons when regressed together.

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Formation Of A Sydno[3,4- A]Indolone And Reactions Thereof, Ryan Christopher Vikan Jan 2007

Formation Of A Sydno[3,4- A]Indolone And Reactions Thereof, Ryan Christopher Vikan

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In the present work, a synthetic route to the formation of a sydno[3,4- a]indolone was explored in the hope of attaining the first example of a fused-ring sydnone with an sp2-hybridized bridge. Formation of this product and exploration of its chemical behavior was anticipated to be of particular interest to the formation of NO-releasing prodrugs. A direct synthetic pathway to yield the target sydnoindolone starting from 3-(2-methoxycarbonylphenyl)sydnone and reaction with a base was proposed and explored. Attempted formation and isolation of the target sydnoindolone proved impossible under a variety of different conditions, undoubtedly due to the instability of this …

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Structure And Biosynthesis Of Heat-Stable Antifungal Factor (Hsaf), A Broad-Spectrum Antimycotic With A Novel Mode Of Action, Fengan Yu, Kathia Zaleta-River, Xiangcheng Zhu, Justin Huffman, Jeffrey C. Millet, Steven D. Harris, Gary Y. Yuen, Xing-Cong Li, Liangcheng Du Jan 2007

Structure And Biosynthesis Of Heat-Stable Antifungal Factor (Hsaf), A Broad-Spectrum Antimycotic With A Novel Mode Of Action, Fengan Yu, Kathia Zaleta-River, Xiangcheng Zhu, Justin Huffman, Jeffrey C. Millet, Steven D. Harris, Gary Y. Yuen, Xing-Cong Li, Liangcheng Du

Department of Chemistry: Faculty Publications

A screen for antifungal compounds from Lysobacter enzymogenes strain C3, a bacterial biological control agent of fungal diseases, has previously led to the isolation of heat-stable antifungal factor (HSAF). HSAF exhibits inhibitory activities against a wide range of fungal species and shows a novel mode of antifungal action by disrupting the biosynthesis of a distinct group of sphingolipids. We have now determined the chemical structure of HSAF, which is identical to that of dihydromaltophilin, an antifungal metabolite with a unique macrocyclic lactam system containing a tetramic acid moiety and a 5,5,6-tricyclic skeleton. We have also identified the genetic locus responsible …

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Dna Multiplex Hybridization On Microarrays And Thermodynamic Stability In Solution: A Direct Comparison, Daniel J. Fish, M. Todd Horne, Greg P. Brewood, Jim P. Goodarzi, Saba Alemayehu, Ashwini Bhandiwad, Robert P. Searles, Albert S. Benight Jan 2007

Dna Multiplex Hybridization On Microarrays And Thermodynamic Stability In Solution: A Direct Comparison, Daniel J. Fish, M. Todd Horne, Greg P. Brewood, Jim P. Goodarzi, Saba Alemayehu, Ashwini Bhandiwad, Robert P. Searles, Albert S. Benight

Chemistry Faculty Publications and Presentations

Hybridization intensities of 30 distinct short duplex DNAs measured on spotted microarrays, were directly compared with thermodynamic stabilities measured in solution. DNA sequences were designed to promote formation of perfect match, or hybrid duplexes containing tandem mismatches. Thermodynamic parameters DeltaH degrees , DeltaS degrees and DeltaG degrees of melting transitions in solution were evaluated directly using differential scanning calorimetry. Quantitative comparison with results from 63 multiplex microarray hybridization experiments provided a linear relationship for perfect match and most mismatch duplexes. Examination of outliers suggests that both duplex length and relative position of tandem mismatches could be important factors contributing to …

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Oxidative Dna Damage In Mild Cognitive Impairment And Late-Stage Alzheimer's Disease, Mark A. Lovell, William R. Markesbery Jan 2007

Oxidative Dna Damage In Mild Cognitive Impairment And Late-Stage Alzheimer's Disease, Mark A. Lovell, William R. Markesbery

Chemistry Faculty Publications

Increasing evidence supports a role for oxidative DNA damage in aging and several neurodegenerative diseases including Alzheimer's disease (AD). Attack of DNA by reactive oxygen species (ROS), particularly hydroxyl radicals, can lead to strand breaks, DNA–DNA and DNA–protein cross-linking, and formation of at least 20 modified bases adducts. In addition, α,β-unsaturated aldehydic by-products of lipid peroxidation including 4-hydroxynonenal and acrolein can interact with DNA bases leading to the formation of bulky exocyclic adducts. Modification of DNA bases by direct interaction with ROS or aldehydes can lead to mutations and altered protein synthesis. Several studies of DNA base adducts in late-stage …

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Supramolecular Usefulness Of Hexamethylenetetramine, Philias Daka Jan 2007

Supramolecular Usefulness Of Hexamethylenetetramine, Philias Daka

Masters Theses

Because non-covalent contacts are important to the design and construction of materials with functional applications, efforts that seek to uncover chemical features responsible for the assembly of multimolecular arrays hold current interest. The building-block approach is one strategy that has been successfully employed for the construction of molecular assemblies. By designing molecular components with complementary functional groups, the construction of predictable supramolecular motifs is possible. Although various modes of molecular alignment have been generated using this strategy, the extension of low dimensional motifs (discrete and 1-D patterns) to 2- and 3-D patterns remain a current challenge.

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Identification And Characterization Of A New Tubulin-Binding, Susan L. Mooberry, Kimberly N. Weiderhold, Sivanesan Dakshanamurthy, Ernest Hamel, Edith J. Banner, Anastasia Kharlamova, Jonathan Hempel, John T. Gupton, Milton L. Brown Jan 2007

Identification And Characterization Of A New Tubulin-Binding, Susan L. Mooberry, Kimberly N. Weiderhold, Sivanesan Dakshanamurthy, Ernest Hamel, Edith J. Banner, Anastasia Kharlamova, Jonathan Hempel, John T. Gupton, Milton L. Brown

Chemistry Faculty Publications

We studied the mechanism of action of 3,5-dibromo-4-(3,4-dimethoxyphenyl)-1H-pyrrole-2-carboxylic acid ethyl ester (JG-03-14) and found that it is a potent microtubule depolymerizer. JG-03-14 caused a dose-dependent loss of cellular microtubules, formation of aberrant mitotic spindles, accumulation of cells in the G2/M phase of the cell cycle, and Bcl-2 phosphorylation. These events culminated in the initiation of apoptosis, as evidenced by the caspase 3-dependent cleavage of poly(ADP-ribose) polymerase (PARP). JG-03-14 has antiproliferative activity against a wide range of cancer cell lines, with an average IC50 value of 62 nM, and it is a poor substrate for transport …

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Computational Models To Predict The Inhibition Of Cytochrome P450 3a4 By Selected Natural Compounds, Sushma Thotakura Jan 2007

Computational Models To Predict The Inhibition Of Cytochrome P450 3a4 By Selected Natural Compounds, Sushma Thotakura

Theses and Dissertations

Cytochrome P450 3A4 (CYP3A4) plays a pivotal role in the metabolism of xenobiotics. Methylenedioxobenzene containing natural products have been shown to inhibit CYP3A4. Given that these compounds are widely distributed in nature there is a strong potential for drug interaction with many plants used for dietary or medicinal purposes. In this research we have developed two different computational models (Comparative Molecular Field Model and Artificial Neural Network Model) to assist in the identification of potentially strong inhibitors that could be further studied for potential inhibitory effects. These models were used to screen for the CYP3A4 inhibitory effects of 100 naturally …

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Evaluation And Characterization Of Some Biologically Active Coumarin Derived Sulfonamides, Harish Gosike Jan 2007

Evaluation And Characterization Of Some Biologically Active Coumarin Derived Sulfonamides, Harish Gosike

Theses and Dissertations

Sulfonamide drugs discovered in the 1930's were the first effective chemotherapeutic agents to be employed for the prevention and cure of bacterial infections in humans. Bacterial resistance to these drugs over the years has led to the development of new variety of sulfonamide derivatives. Recently Chohan et al. synthesized a series of coumarin derived sulfonamides and their chemical structures have been established. In this report, we present some microbiological studies to establish the antibacterial characters of these compounds. In order to establish their chemical structure-biological activity relationship, electrochemical and spectroscopic studies have been conducted. Antibacterial studies conducted on these compounds …

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Identification Of Potential Organic Contributors In Carbonaceous Aerosols: Enhanced Uv Absorption Spectra, Anand Mangu Jan 2007

Identification Of Potential Organic Contributors In Carbonaceous Aerosols: Enhanced Uv Absorption Spectra, Anand Mangu

Theses and Dissertations

Direct aerosol climate effects include light scattering and absorption that present the largest uncertainties in the assessment of radiative forcing. To estimate the overall effect of aerosols on climate the relative amounts of scattering and absorption must be known. Determination of aerosol UV-absorption spectra is the primary focus of this thesis research. Aerosol samples were collected in Mexico City in 2003 and 2006 as a part of Mexico City Metropolitan Area field study and also at Little Rock. UV-visible absorption spectra of these aerosol samples have been obtained by using an integrating sphere coupled to a UV-visible spectrometer and compared …

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Synthesis And Characterization Of Highly Conductive Polypyrrole And Polypyrrole/Lignosulfonate/Graphite Composites, Aopeau Imvittaya Jan 2007

Synthesis And Characterization Of Highly Conductive Polypyrrole And Polypyrrole/Lignosulfonate/Graphite Composites, Aopeau Imvittaya

Theses and Dissertations

Polypyrrole (PPy) is one of the conductive polymers frequently used in commercial applications, mainly due to its long-term stability and the possibility of forming homopolymers or composites with optimal properties. Polypyrroles were prepared by the chemical polymerization of pyrrole using various methods. The effects of several parameters such as oxidant, dopant type, additives and reaction conditions on the properties of PPy were investigated. In addition, PPy/graphite composites were prepared because graphite is highly conductive and effectively incorporated into the polymer matrix during the polymerization. The amount of graphite in the composite was varied to determine the maximimum conductivity achievable in …

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Antibacterial Targets In Fatty Acid Biosynthesis, H. Tonie Wright, Kevin A. Reynolds Jan 2007

Antibacterial Targets In Fatty Acid Biosynthesis, H. Tonie Wright, Kevin A. Reynolds

Chemistry Faculty Publications and Presentations

The fatty acid biosynthesis pathway is an attractive but still largely unexploited target for development of new anti-bacterial agents. The extended use of the anti-tuberculosis drug isoniazid and the antiseptic triclosan, which are inhibitors of fatty acid biosynthesis, validates this pathway as a target for anti-bacterial development. Differences in subcellular organization of the bacterial and eukaryotic multi-enzyme fatty acid synthase systems offer the prospect of inhibitors with host vs. target specificity. Platensimycin, platencin, and phomallenic acids, newly discovered natural product inhibitors of the condensation steps in fatty acid biosynthesis, represent new classes of compounds with antibiotic potential. An almost complete …

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Probing Reactivity And Substrate Specificity Of Both Subunits Of The Dimeric Mycobacterium Tuberculosis Fabh Using Alkyl-Coa Disulfide Inhibitors And Acyl-Coa Substrates, Sarbjot Sachdeva, Faik Musayev, Mamoun M. Alhamadsheh, J. Neel Scarsdale, H. Tonie Wright, Kevin A. Reynolds Jan 2007

Probing Reactivity And Substrate Specificity Of Both Subunits Of The Dimeric Mycobacterium Tuberculosis Fabh Using Alkyl-Coa Disulfide Inhibitors And Acyl-Coa Substrates, Sarbjot Sachdeva, Faik Musayev, Mamoun M. Alhamadsheh, J. Neel Scarsdale, H. Tonie Wright, Kevin A. Reynolds

Chemistry Faculty Publications and Presentations

The dimeric Mycobacterium tuberculosis FabH (mtFabH) catalyses a Claisen-type condensation between an acyl-CoA and malonyl-acyl carrier protein (ACP) to initiate the Type II fatty acid synthase cycle. To analyze the initial covalent acylation of mtFabH with acyl-CoA, we challenged it with mixture of C6-C20 acyl-CoAs and the ESI-MS analysis showed reaction at both subunits and a strict specificity for C12 acyl CoA. Crystallographic and ESI-MS studies of mtFabH with a decyl-CoA disulfide inhibitor revealed a decyl chain bound in acyl-binding channels of both subunits through disulfide linkage to the active site cysteine. These data provide the first unequivocal evidence that …

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Singlet Oxygen Generation Using New Fluorene-Based Photosensitizers Under One- And Two-Photon Excitation, Stephen James Andrasik Jan 2007

Singlet Oxygen Generation Using New Fluorene-Based Photosensitizers Under One- And Two-Photon Excitation, Stephen James Andrasik

Electronic Theses and Dissertations

Molecular oxygen in its lowest electronically excited state plays an important roll in the field of chemistry. This excited state is often referred to as singlet oxygen and can be generated in a photosensitized process under one- or two-photon excitation of a photosensitizer. It is particularly useful in the field of photodynamic cancer therapy (PDT) where singlet oxygen formation can be used to destroy cancerous tumors. The use of two-photon activated photosensitizers possesses great potential in the field of PDT since near-IR light is used to activate the sensitizer, resulting in deeper penetration of light into biological tissue, less photobleaching …

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Two-Photon 3d Optical Data Storage Via Fluorescence Modulation Of Fluorene Dyes By Photochromic Diarylethenes, Claudia Corredor Jan 2007

Two-Photon 3d Optical Data Storage Via Fluorescence Modulation Of Fluorene Dyes By Photochromic Diarylethenes, Claudia Corredor

Electronic Theses and Dissertations

Three-dimensional (3D) optical data storage based on two-photon processes provides highly confined excitation in a recording medium and a mechanism for writing and reading data with less cross talk between multiple memory layers, due to the quadratic dependence of two photon absorption (2PA) on the incident light intensity. The capacity for highly confined excitation and intrinsic 3D resolution affords immense information storage capacity (up to 1012 bits/cm3). Recently, the use of photochromic materials for 3D memory has received intense interest because of several major advantages over current optical systems, including their erasable/rewritable capability, high resolution, and high sensitivity. This work …

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Analytical Potential Of Polymerized Liposomes Bound To Lanthanide Ions For Qualitative And Quantitative Analysis Of Proteins, Marina Santos Jan 2007

Analytical Potential Of Polymerized Liposomes Bound To Lanthanide Ions For Qualitative And Quantitative Analysis Of Proteins, Marina Santos

Electronic Theses and Dissertations

One of the intriguing features of biological systems is the prevalence of highly selective and often very strong interactions among different cellular components. Such interactions play a variety of organizational, mechanical, and physiological roles at the cellular and organism levels. Antigen-antibody complexes are representative examples of highly selective and potent interactions involving proteins. The marked specificity of protein-antibody complexes have led to a wide range of applications in cellular and molecular biology related research. They have become an integral research tool in the present genomic and proteomic era. Unfortunately, the production of selective tools based on antigen-antibody interactions requires cumbersome …

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Synthesis And Functionalizations Of Tetrapyrrole Derivatives, Lijuan Jiao Jan 2007

Synthesis And Functionalizations Of Tetrapyrrole Derivatives, Lijuan Jiao

LSU Doctoral Dissertations

Chapter 1 of this Dissertation presents a brief overview of the history of tetrapyrrole derivatives and of their fundamental properties. Overviews of porphyrins, benzoporphyrins, chlorins and porphycenes are presented. Work presented in Chapter 2 through Chapter 4 mainly focuses on the syntheses and functionalization of chromophore-extended porphyrin derivatives. Several new synthetic routes for the syntheses and functionalizations of extended porphyrins either at the β-position or at the meso-position of porphyrin are developed. From these improved synthetic routes, the regio-selective syntheses of porphyrin derivatives are described. Chapter 2 mainly focuses on the syntheses of β,β'-fused methylenepropanoporphyrins and related porphyrin dimers. Chapter …

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The Spectral And Photophysical Characterization Of Water Solubilizing Metal Phthalocyanines For Highly Sensitive Detection In Biological Studies, Vera Tamisha Verdree Jan 2007

The Spectral And Photophysical Characterization Of Water Solubilizing Metal Phthalocyanines For Highly Sensitive Detection In Biological Studies, Vera Tamisha Verdree

LSU Doctoral Dissertations

Efforts to improve the technology for DNA analyses stimulated the work presented here to develop a series of fluorescent probes that would aid in the increased multiplexing capabilities allowing the ability to detect multiple targets in a single measurement. Typically, spectral discrimination has been used to identify each DNA fragment in sequencing or diagnostic applications by means of unique emission properties from several labeling dyes. This has been accomplished with labels that fluoresce in the visible region. The limitations with these dyes is the broad emission profile making discrimination difficult, high intrinsic biological fluorescence and structural differences of the dyes …

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Exploring The Binding Of Amine And Sulfonamide Ligands In Rhenium(I) Tricarbonyl And Platinum(Ii) Complexes, Anna Maria Christoforou Jan 2007

Exploring The Binding Of Amine And Sulfonamide Ligands In Rhenium(I) Tricarbonyl And Platinum(Ii) Complexes, Anna Maria Christoforou

LSU Doctoral Dissertations

Platinum is the metal present in various classes of inorganic medicinal agents directed at important diseases such as cancer or viral infections. Several new Pt(II) complexes of polyamine ligands bearing a dansyl moiety linked by a sulfonamide group were prepared; in some cases the sulfonamide nitrogen formed a bond to Pt. The sulfonamido group donates strongly to Pt and places the dansyl group close to a vacant coordination position, allowing it to stack with bound guanine base (G) when G binds. The emission of the fluorophore decreases with decreasing distance to Pt. Metal nuclide radiopharmaceuticals contain a metal core and …

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