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Chemistry Faculty Publications

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Articles 541 - 570 of 1129

Full-Text Articles in Chemistry

Interaction Between Lubricants Containing Phosphate Ester Additives And Stainless Steels, David W. Johnson, Matthew Bachus, John E. Hils May 2013

Interaction Between Lubricants Containing Phosphate Ester Additives And Stainless Steels, David W. Johnson, Matthew Bachus, John E. Hils

Chemistry Faculty Publications

One way to improve fuel efficiency in today’s jet aircraft engines is to create an environment for higher operating temperatures and speeds. New and improved lubricants and bearing materials must be developed to remain stable in these elevated operating temperatures. Three lubricants, with varying amounts of tricresyl phosphate added as an anti-wear/extreme pressure additive were tested on two different stainless steels at varying temperatures ranging from 300 °C to 350 °C in vacuum. Significant decomposition of the lubricant base-stocks and the phosphate ester additive did occur in most of the trials resulting in the formation of carboxylic acids and phenols. …

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5,5'-Dichloro-2,2'-Dimethoxybiphenyl, Hans-Joachim Lehmler, Huimin Wu, Sean Parkin May 2013

5,5'-Dichloro-2,2'-Dimethoxybiphenyl, Hans-Joachim Lehmler, Huimin Wu, Sean Parkin

Chemistry Faculty Publications

In the title molecule, C14H12Cl2O2, the dihedral angle between the least-square planes of the benzene rings is 62.17 (6)°. Both methoxy groups are slightly out of the plane of the benzene rings to which they are attached, making dihedral angles of 4.22 (18) and 18.82 (16)°.

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Patent: Dual Function Proteins For Treating Metabolic Disorders, Brian R. Boettcher, Shari L. Caplan, Susan E. Cellitti, Douglas S. Daniels, Norio Hamamatsu, Bernhard Hubert Geierstanger, Stuart Licht, Andreas Loew, Stephen Craig Weldon Apr 2013

Patent: Dual Function Proteins For Treating Metabolic Disorders, Brian R. Boettcher, Shari L. Caplan, Susan E. Cellitti, Douglas S. Daniels, Norio Hamamatsu, Bernhard Hubert Geierstanger, Stuart Licht, Andreas Loew, Stephen Craig Weldon

Chemistry Faculty Publications

The present invention relates to new proteins comprising fibroblast growth factor 2 1 (FGF21 ) and other metabolic regulators known to improve metabolic profiles in subjects to whom they are administered.

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The Low-Resolution Structure Of Nascent High Density Lipoprotein Reconstituted With Dmpc With And Without Cholesterol Reveals A Mechanism For Particle Expansion, Valentin Gogonea, Gary S. Gerstenecker, Zhiping Wu, Xavier Lee, Celalettin Topbas, Matthew A. Wagner, Thomas C. Tallant, Jonathan D. Smith, Phil Callow, Vitaliy Pipich, Helen Malet, Guy Schoehn, Joseph A. Didonato, Stanley L. Hazen Apr 2013

The Low-Resolution Structure Of Nascent High Density Lipoprotein Reconstituted With Dmpc With And Without Cholesterol Reveals A Mechanism For Particle Expansion, Valentin Gogonea, Gary S. Gerstenecker, Zhiping Wu, Xavier Lee, Celalettin Topbas, Matthew A. Wagner, Thomas C. Tallant, Jonathan D. Smith, Phil Callow, Vitaliy Pipich, Helen Malet, Guy Schoehn, Joseph A. Didonato, Stanley L. Hazen

Chemistry Faculty Publications

High density lipoproteins (HDL) are athero-protective particles under investigation as potential therapeutic agents for cardiovascular disease. We applied small angle neutron scattering (SANS) with contrast variation to obtain the low resolution structure of nascent HDL (nHDL) reconstituted with dimyristoyl phosphatidyl choline (DMPC), apoA1:DMPC (1:80, mol:mol). The overall shape of the entire particle is discoidal, with low resolution architecture of apoA1 visualized as an open, contorted, and slightly out of plane structure with three arms, while the low resolution shape of the lipid phase is an oblate ellipsoid that fits well within the protein shape. Modeling studies incorporating the SANS data …

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3,4',5-Trichlorobiphenyl-4-Yl 2,2,2-Trichloroethyl Sulfate, Hans-Joachim Lehmler, Xianran He, Michael W. Duffel, Sean Parkin Apr 2013

3,4',5-Trichlorobiphenyl-4-Yl 2,2,2-Trichloroethyl Sulfate, Hans-Joachim Lehmler, Xianran He, Michael W. Duffel, Sean Parkin

Chemistry Faculty Publications

Crystals of the title compound, C14H8Cl6O4S, are twinned by inversion, with unequal components [0.85 (3):0.15 (3)]. The asymmetric unit contains two independent molecules that are related by a pseudo-inversion center. The Car-O [1.393 (9) and 1.397 (9) Å] and ester S-O bond lengths [1.600 (5) and 1.590 (5) Å] of both molecules are comparable to the structurally related 2,3,5,5-trichlorobiphenyl-4-yl 2,2,2-trichloroethyl sulfate. The dihedral angles between the benzene rings in the two molecules are 37.8 (2) and 35.0 (2)°.

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Patent: Fusion Proteins For Treating Metabolic Disorders, Brian R. Boettcher, Shari L. Caplan, Douglas S. Daniels, Norio Hamamatsu, Stuart Licht, Stephen Craig Weldon Mar 2013

Patent: Fusion Proteins For Treating Metabolic Disorders, Brian R. Boettcher, Shari L. Caplan, Douglas S. Daniels, Norio Hamamatsu, Stuart Licht, Stephen Craig Weldon

Chemistry Faculty Publications

The invention relates to the identification of fusion proteins comprising polypeptide and protein variants of fibroblast growth factor 21 (FGF21) with improved pharmaceutical properties. Also disclosed are methods for treating FGF21 associated disorders, including metabolic conditions.

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Monolayer-Protected Nanoparticle Doped Xerogels As Functional Components Of Amperometric Glucose Biosensors, Michael Hartley Freeman, Jackson R. Hall, Michael C. Leopold Mar 2013

Monolayer-Protected Nanoparticle Doped Xerogels As Functional Components Of Amperometric Glucose Biosensors, Michael Hartley Freeman, Jackson R. Hall, Michael C. Leopold

Chemistry Faculty Publications

First-generation amperometric glucose biosensors incorporating alkanethiolate-protected gold nanoparticles, monolayer protected clusters (MPCs), within a xerogel matrix are investigated as model systems for nanomaterial-assisted electrochemical sensing strategies. The xerogel biosensors are comprised of platinum electrodes modified with composite films of (3-mercaptopropyl)trimethoxy silane xerogel embedded with glucose oxidase enzyme, doped with Au225(C6)75 MPCs, and coated with an outer polyurethane layer. Electrochemistry and scanning/transmission electron microscopy, including cross-sectional TEM, show sensor construction, humidity effects on xerogel structure, and successful incorporation of MPCs. Analytical performance of the biosensor scheme with and without MPC doping of the xerogel is determined from direct glucose injection during …

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Nanoparticle Film Assemblies As Platforms For Electrochemical Biosensing – Factors Affecting Amperometric Signal Enhancement Of Hydrogen Peroxide, Adrienne R. Schmidt, Natalie D. T. Nguyen, Michael C. Leopold Mar 2013

Nanoparticle Film Assemblies As Platforms For Electrochemical Biosensing – Factors Affecting Amperometric Signal Enhancement Of Hydrogen Peroxide, Adrienne R. Schmidt, Natalie D. T. Nguyen, Michael C. Leopold

Chemistry Faculty Publications

Factors affecting the enhanced amperometric signal observed at electrodes modified with polyelectrolyte–gold nanoparticle (Au-NP) composite films, which are potential interfaces for first-generation biosensors, were systematically investigated and optimized for hydrogen peroxide (H2O2) detection. Polyelectrolyte multilayer films embedded with citrate-stabilized gold nanoparticles exhibited high sensitivity toward the oxidation of H2O2. From this Au-NP film assembly, the importance of Au-NP ligand protection, film permeability, the density of Au-NPs within the film, and electronic coupling between Au-NPs (interparticle) and between the film and the electrode (interfacial) were evaluated. Using alternative Au-NPs, including those stabilized with thiols, polymers, and bulky ligands, suggests that the …

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Insights Into The Roles Of Desolvation And Π-Electron Interactions During Dna Polymerization, Edward A. Motea, Irene Lee, Anthony J. Berdis Mar 2013

Insights Into The Roles Of Desolvation And Π-Electron Interactions During Dna Polymerization, Edward A. Motea, Irene Lee, Anthony J. Berdis

Chemistry Faculty Publications

This report describes the use of several isosteric non-natural nucleotides as probes to evaluate the roles of nucleobase shape, size, solvation energies, and π-electron interactions as forces influencing key kinetic steps of the DNA polymerization cycle. Results are provided using representative high- and low-fidelity DNA polymerases. Results generated with the E. coli Klenow fragment reveal that this high-fidelity polymerase utilizes hydrophobic nucleotide analogues with higher catalytic efficiencies compared to hydrophilic analogues. These data support a major role for nucleobase desolvation during nucleotide selection and insertion. In contrast, the low-fidelity HIV-1 reverse transcriptase discriminates against hydrophobic analogues and only tolerates non-natural …

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Effects Of The Protein Environment On The Spectral Properties Of Tryptophan Radicals In Pseudomonas Aeruginosa Azurin, Caterina Bernini, Tadeusz AndrunióW, Massimo Olivucci, Rebecca Pogni, Riccardo Basosi, Adalgisa Sinicropi Mar 2013

Effects Of The Protein Environment On The Spectral Properties Of Tryptophan Radicals In Pseudomonas Aeruginosa Azurin, Caterina Bernini, Tadeusz AndrunióW, Massimo Olivucci, Rebecca Pogni, Riccardo Basosi, Adalgisa Sinicropi

Chemistry Faculty Publications

Many biological electron-transfer reactions involve short-lived tryptophan radicals as key reactive intermediates. While these species are difficult to investigate, the recent photogeneration of a long-lived neutral tryptophan radical in two Pseudomonas aeruginosa azurin mutants (Az48W and ReAz108W) made it possible to characterize the electronic, vibrational, and magnetic properties of such species and their sensitivity to the molecular environment. Indeed, in Az48W the radical is embedded in the hydrophobic core while, in ReAz108W it is solvent-exposed. Here we use density functional theory and multiconfigurational perturbation theory to construct quantum-mechanics/molecular-mechanics models of Az48W* and ReAz108W* capable of reproducing specific features of their …

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Tuning Photophysical Properties And Improving Nonlinear Absorption Of Pt(Ii) Diimine Complexes With Extended Π-Conjugation In The Acetylide Ligands, Rui Liu, Alexander Azenkeng, Dapeng Zhou, Yuhao Li, Ksenija D. Glusac, Wenfang Sun Mar 2013

Tuning Photophysical Properties And Improving Nonlinear Absorption Of Pt(Ii) Diimine Complexes With Extended Π-Conjugation In The Acetylide Ligands, Rui Liu, Alexander Azenkeng, Dapeng Zhou, Yuhao Li, Ksenija D. Glusac, Wenfang Sun

Chemistry Faculty Publications

Two new Pt(II) 4,4'-di(5,9-diethyltridecan-7-yl)-2,2'-bipyridine complexes (1 and 2,) bearing 9,9-diethyl-2-ethynyl-7-(2-(4-nitrophenyl)ethynyl)-9H-fluorene ligand and N-(4-(2-(9,9-diethyl-7-ethynyl-9H-fluoren-2-yl)ethynyl)phenyl)-N-phenylbenzeneamine ligand, respectively, were synthesized and characterized. Their photophysical properties were investigated systematically by UV vis absorption, emission, and transient absorption (TA) spectroscopy, and the nonlinear absorption was studied by nonlinear transmission technique. Theoretical TD-DFT calculations using the CAM-B3LYP functional were carried out to determine the nature of the singlet excited electronic states and to assist in the assignment of significant transitions observed in experiments. Complex 1 exhibits an intense, structureless absorption band at ca. 397 nm in CH2Cl2 solution, which is attributed to mixed metal-to-ligand charge transfer …

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Oxidation Of Adenosine And Inosine: The Chemistry Of 8-Oxo-7,8-Dihydropurines, Purine Iminoquinones, And Purine Quinones As Observed By Ultrafast Spectroscopy, Denis I. Nilov, Dmitry Y. Komarov, Maxim S. Panov, Kanykey E. Karabaeva, Andrey S. Mereshchenko, Alexander N. Tarnovsky, R. Marshall Wilson Mar 2013

Oxidation Of Adenosine And Inosine: The Chemistry Of 8-Oxo-7,8-Dihydropurines, Purine Iminoquinones, And Purine Quinones As Observed By Ultrafast Spectroscopy, Denis I. Nilov, Dmitry Y. Komarov, Maxim S. Panov, Kanykey E. Karabaeva, Andrey S. Mereshchenko, Alexander N. Tarnovsky, R. Marshall Wilson

Chemistry Faculty Publications

Oxidative damage to purine nucleic acid bases proceeds through quinoidal intermediates derived from their corresponding 8-oxo-7,8-dihydropurine bases. Oxidation studies of 8-oxo-7,8-dihyroadenosine and 8-oxo-7,8-dihydroinosine indicate that these quinoidal species can produce stable cross links with a wide variety of nucleophiles in the 2-positions of the purines. An azide precursor for the adenosine iminoquinone has been synthesized and applied in ultrafast transient absorption spectroscopic studies. Thus, the adenosine iminoquinone can be observed directly, and its susceptibility to nudeophilic attack with various nucleophiles as well as the stability of the resulting cross linked species have been evaluated Finally, these observations indicate that this …

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Development, Validation And Pilot Screening Of An In Vitro Multi-Cellular Three-Dimensional Cancer Spheroid Assay For Anti-Cancer Drug Testing, Rati Lama, Lin Zhang, Janine M. Naim, Jennifer Williams, Aimin Zhou, Bin Su Feb 2013

Development, Validation And Pilot Screening Of An In Vitro Multi-Cellular Three-Dimensional Cancer Spheroid Assay For Anti-Cancer Drug Testing, Rati Lama, Lin Zhang, Janine M. Naim, Jennifer Williams, Aimin Zhou, Bin Su

Chemistry Faculty Publications

It has been demonstrated that two-dimensional (2D) monolayer cancer cell proliferation assay for anti-cancer drug screening is a very artificial model and cannot represent the characteristics of three-dimensional (3D) solid tumors. The multi-cellular in vitro 3D tumor spheroid model is of intermediate complexity, and can provide a bridge to the gap between the complex in vivo tumors and simple in vitro monolayer cell cultures. In this study, a simple and cost-effective cancer 3D spheroid assay suitable for small molecule anti-cancer compound screening was developed, standardized and validated on H292 non-small lung cancer cell line. A pilot screening with this assay …

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An Analytical Look At Glen Helen Nature Preserve Fall 2013, Audrey E. Mcgowin, Seth W. Brittle, Jacob Doolin, Dustin Estridge, Anna Foote, Shannon Hennley, Megan Huddleson, Robert Johnson, Abraham Kemboi, Carlie Mcgrath, John Mcgrath, Renata Mitton, David Roland, Nicholas Rose Jan 2013

An Analytical Look At Glen Helen Nature Preserve Fall 2013, Audrey E. Mcgowin, Seth W. Brittle, Jacob Doolin, Dustin Estridge, Anna Foote, Shannon Hennley, Megan Huddleson, Robert Johnson, Abraham Kemboi, Carlie Mcgrath, John Mcgrath, Renata Mitton, David Roland, Nicholas Rose

Chemistry Faculty Publications

No abstract provided.

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Peroxynitrite Activity Of Hemin-Functionalized Reduced Graphene Oxide, Raluca Oprea, Serban F. Peteu, Palaniappan Subramanian, Wang Qi, Emmanualle Pichonat, Henri Happy, Mekki Bayachou, Rabah Boukherroub, Sabine Szunerits Jan 2013

Peroxynitrite Activity Of Hemin-Functionalized Reduced Graphene Oxide, Raluca Oprea, Serban F. Peteu, Palaniappan Subramanian, Wang Qi, Emmanualle Pichonat, Henri Happy, Mekki Bayachou, Rabah Boukherroub, Sabine Szunerits

Chemistry Faculty Publications

Conducting interfaces modified with reduced graphene oxide (rGO) have shown improved electrochemical response for different analytes. The efficient formation of functionalized rGO based materials is thus of current interest for the development of sensitive and selective biosensors. Herein, we report a simple and environmentally friendly method for the formation of a hemin-functionalized rGO hybrid nanomaterial that exhibits remarkable sensitivity to peroxynitrite (ONOO−) in solution. The hemin-functionalized rGO hybrid nanomaterial was formed by mixing an aqueous solution of graphene oxide (GO) with hemin and sonicating the suspension for 5 h at room temperature. In addition to playing a key role in …

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Metastable Nanostructured Metallized Fluoropolymer Composites For Energetics, Hannah A. Miller, Bradley S. Kusel, Seth T. Danielson, James W. Neat, Eryn K. Avjian, Scott N. Pierson, Stephen M. Budy, David W. Ball, Scott T. Iacono, Sharon C. Kettwich Jan 2013

Metastable Nanostructured Metallized Fluoropolymer Composites For Energetics, Hannah A. Miller, Bradley S. Kusel, Seth T. Danielson, James W. Neat, Eryn K. Avjian, Scott N. Pierson, Stephen M. Budy, David W. Ball, Scott T. Iacono, Sharon C. Kettwich

Chemistry Faculty Publications

Fluoropolymers have long served as potent oxidizers for metal-based pyrolant designs for the preparation of energetic materials. Commercial perfluoropolyethers (PFPEs), specifically known as Fomblins®, are well-known to undergo accelerated thermal degradation in the presence of native metals and Lewis acids producing energetically favorable metal fluoride species. This study employs the use of PFPEs to coat nano-aluminum (n-Al) and under optimized stoichiometric formulations, harness optimized energy output. The PFPEs serve as ideal oxidizers of n-Al because they are non-volatile, viscous liquids that coat the particles thereby maximizing surface interactions. The n-Al/PFPE blended combination is required to interface with an epoxy-based matrix …

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Combined Self-Consistent-Field And Spin-Flip Tamm–Dancoff Density Functional Approach To Potential Energy Surfaces For Photochemistry, Xuefei Xu, Samer Gozem, Massimo Olivucci, Donald G. Truhlar Jan 2013

Combined Self-Consistent-Field And Spin-Flip Tamm–Dancoff Density Functional Approach To Potential Energy Surfaces For Photochemistry, Xuefei Xu, Samer Gozem, Massimo Olivucci, Donald G. Truhlar

Chemistry Faculty Publications

We present a new approach to calculating potential energy surfaces for photochemical reactions by combining self-consistent-field calculations for single-reference ground and excited states with symmetry-corrected spin-flip Tamm-Dancoff approximation calculations for multireference electronic states. The method is illustrated by an application with the M05-2X exchange-correlation functional to cis-trans isomerization of the penta-2,4-dieniminium cation, which is a model (with three conjugated double bonds) of the protonated Schiff base of retinal. We find good agreement with multireference configuration interaction-plus-quadruples (MRCISD+Q) wave function calculations along three key paths in the strong-interaction region of the ground and first excited singlet states.

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Single-Cell Imaging And Spectroscopic Analyses Of Cr(Vi) Reduction On The Surface Of Bacterial Cells, Yuanmin Wang, Papatya C. Sevinc, Sara M. Belchik, Jim Fredrickson, Liang Shi, H. Peter Lu Jan 2013

Single-Cell Imaging And Spectroscopic Analyses Of Cr(Vi) Reduction On The Surface Of Bacterial Cells, Yuanmin Wang, Papatya C. Sevinc, Sara M. Belchik, Jim Fredrickson, Liang Shi, H. Peter Lu

Chemistry Faculty Publications

We investigate the single-cell reduction of toxic Cr(VI) by the dissimilatory metal-reducing bacterium Shewanella oneidensis MR-1 (MR-1), an important bioremediation process, using Raman spectroscopy and scanning electron microscopy (SEM) combined with energy-dispersive X-ray spectroscopy (EDX). Our experiments indicate that the toxic, highly soluble Cr(VI) can be efficiently reduced to less toxic, nonsoluble Cr2O3 nanoparticles by MR-1. Cr2O3 is observed to emerge as nanoparticles adsorbed on the cell surface and its chemical nature is identified by EDX imaging and Raman spectroscopy. Co-localization of Cr2O3 and cytochromes by EDX imaging and Raman spectroscopy suggests a terminal reductase role for MR-1 surface-exposed cytochromes …

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Global Sampling Of The Photochemical Reaction Paths Of Bromoform By Ultrafast Deep-Uv Through Near-Ir Transient Absorption And Ab Initio Multiconfigurational Calculations, Alexander N. Tarnovsky, S. K. Pal, A. S. Mereshchenko, E. V. Butaeva, Patrick Z. El-Khoury Jan 2013

Global Sampling Of The Photochemical Reaction Paths Of Bromoform By Ultrafast Deep-Uv Through Near-Ir Transient Absorption And Ab Initio Multiconfigurational Calculations, Alexander N. Tarnovsky, S. K. Pal, A. S. Mereshchenko, E. V. Butaeva, Patrick Z. El-Khoury

Chemistry Faculty Publications

Ultrafast deep-ultraviolet through near infrared (210-950 nm) transient absorption spectroscopy complemented by ab initio multiconfigurational calculations offers a global description of the photochemical reaction pathways of bromoform following 255-nm excitation in methylcyclohexane and acetonitrile solutions. Photoexcitation of CHBr3 leads to the ground-state iso-CHBr3 product in a large quantum yield (∼35), formed through two different mechanisms: concerted excited-state isomerization and cage-induced isomerization through the recombination of the nascent radical pair. These two processes take place on different time scales of tens of femtoseconds and several picoseconds, respectively. The novel ultrafast direct isomerization pathway proposed herein is consistent with the occurrence of …

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Synthesis And Evaluation Of Some 17-Acetamidoandrostane And N,N-Dimethyl-7-Deoxycholic Amide Derivatives As Cytotoxic Agents: Structure/Activity Studies, Yanmin Huang, Jianguo Cui, Linyi Jia, Chunfang Gan, Huacan Song, Chun Zeng, Aimin Zhou Jan 2013

Synthesis And Evaluation Of Some 17-Acetamidoandrostane And N,N-Dimethyl-7-Deoxycholic Amide Derivatives As Cytotoxic Agents: Structure/Activity Studies, Yanmin Huang, Jianguo Cui, Linyi Jia, Chunfang Gan, Huacan Song, Chun Zeng, Aimin Zhou

Chemistry Faculty Publications

Using pregnenolone and 7-deoxycholic acid as starting materials, some 17-acetamidoandrostane and N,N-dimethyl-7-deoxycholic amide derivatives were synthesized. The cytotoxicity of the synthesized compounds was tested in vitro against two tumor cell lines: SGC 7901 (human gastric carcinoma) and Bel 7404 (human liver carcinoma). The result showed that the blockage of the interaction of the amide group with outside groups might cause a decrease of the cytotoxicity, and an O-benzyloximino group at the 3-position of N,N-dimethyl-7-deoxycholic amide could enhance the cytotoxic activity of the compound. The information obtained from the studies provides the structure-activity relationship for these compounds and may be useful …

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Charge-Pairing Interactions Control The Conformational Setpoint And Motions Of The Fmn Domain In Neuronal Nitric Oxide Synthase, Mohammad Mahfuzul Haque, Mekki Bayachou, Mohammed A. Fadlalla, Deborah Durra, Dennis J. Stuehr Jan 2013

Charge-Pairing Interactions Control The Conformational Setpoint And Motions Of The Fmn Domain In Neuronal Nitric Oxide Synthase, Mohammad Mahfuzul Haque, Mekki Bayachou, Mohammed A. Fadlalla, Deborah Durra, Dennis J. Stuehr

Chemistry Faculty Publications

The NOS (nitric oxide synthase; EC 1.14.13.39) enzymes contain a C-terminal flavoprotein domain [NOSred (reductase domain of NOS)] that binds FAD and FMN, and an N-terminal oxygenase domain that binds haem. Evidence suggests that the FMN-binding domain undergoes large conformational motions to shuttle electrons between the NADPH/FAD-binding domain [FNR (ferredoxin NADP-reductase)] and the oxygenase domain. Previously we have shown that three residues on the FMN domain (Glu(762), Glu(816) and Glu(819)) that make charge-pairing interactions with the FNR help to slow electron flux through nNOSred (neuronal NOSred). In the present study, we show that charge neutralization or reversal at each of …

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Kamlet Laboratories And Clinitest: Idea To Product, Dean F. Martin, Brodie A. Reiger Jan 2013

Kamlet Laboratories And Clinitest: Idea To Product, Dean F. Martin, Brodie A. Reiger

Chemistry Faculty Publications

This paper examines the process of development of Clinitest pills that could be used in clinics or physicians' offices for rapid, convenient analysis of glucose and other components of clinical interest. It was invented by Dr. Jonas Kamlet. We were able to follow the process because his papers are accessible (as The Kamlet Laboratories Collection) at the University of South Florida Library. The accessibility of these papers gives an opportunity to see steps in the development of a successful product from conception to patent and commercialization. Kamlet, a consulting chemist, took the invention to Miles Laboratories of Elkhart, Indiana, in …

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Preparation Of Phosphonoterephthalic Acids Via Palladium-Catalyzed Coupling Of Aromatic Iodoesters, Nathaniel Ivan, Vladimir Benin, Alexander Morgan Jan 2013

Preparation Of Phosphonoterephthalic Acids Via Palladium-Catalyzed Coupling Of Aromatic Iodoesters, Nathaniel Ivan, Vladimir Benin, Alexander Morgan

Chemistry Faculty Publications

The current article reports in detail the preparation of two phosphonoterephthalic acids: 2-phosphonoterephthalic acid (1) and 2,5-diphosphonoterephthalic acid (2). Efficient, scalable syntheses have been developed for both compounds based on Pd-catalyzed coupling reactions of iodinated terephthalate esters. Phosphonoterephthalic acids are potentially useful as flame-retardant additives or as monomers for the construction of acid-pendant polymer chains.

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Voltage-Controlled Enzyme-Catalyzed Glucose–Gluconolactone Conversion Using A Field-Effect Enzymatic Detector, Siu Tung Yau, Yan Xu, Yang Song, Ye Feng, Jiapeng Wang Jan 2013

Voltage-Controlled Enzyme-Catalyzed Glucose–Gluconolactone Conversion Using A Field-Effect Enzymatic Detector, Siu Tung Yau, Yan Xu, Yang Song, Ye Feng, Jiapeng Wang

Chemistry Faculty Publications

The field-effect enzymatic detection (FEED) technique was used to control the kinetics of the enzymatic conversion of glucose to gluconolactone. The glucose–gluconolactone conversion occurring at an enzyme-immobilized electrode, a well-studied process, was confirmed using mass spectrometry. Electrochemical studies showed that the glucose oxidation current depends on the gating voltage VG and the ion concentration of the sample solution. Additionally, the depletion of glucose in the sample also showed a dependence on VG. FEED was used to detect H2O2 on the zepto-molar level in order to show the ultrasensitive detection capability of the technique. These results, while providing evidence for the …

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Spectroscopic Analysis Of Polymerization And Exonuclease Proofreading By A High-Fidelity Dna Polymerase During Translesion Dna Synthesis, Babho Devadoss, Irene Lee, Anthony J. Berdis Jan 2013

Spectroscopic Analysis Of Polymerization And Exonuclease Proofreading By A High-Fidelity Dna Polymerase During Translesion Dna Synthesis, Babho Devadoss, Irene Lee, Anthony J. Berdis

Chemistry Faculty Publications

High fidelity DNA polymerases maintain genomic fidelity through a series of kinetic steps that include nucleotide binding, conformational changes, phosphoryl transfer, polymerase translocation, and nucleotide excision. Developing a comprehensive understanding of how these steps are coordinated during correct and pro-mutagenic DNA synthesis has been hindered due to lack of spectroscopic nucleotides that function as efficient polymerase substrates. This report describes the application of a non-natural nucleotide designated 5-naphthyl-indole-2′-deoxyribose triphosphate which behaves as a fluorogenic substrate to monitor nucleotide incorporation and excision during the replication of normal DNA versus two distinct DNA lesions (cyclobutane thymine dimer and an abasic site). Transient …

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The Mechanism Of Photo-Hydrosilylation On Silicon And Porous Silicon Surfaces, Kurt W. Kolasinski Jan 2013

The Mechanism Of Photo-Hydrosilylation On Silicon And Porous Silicon Surfaces, Kurt W. Kolasinski

Chemistry Faculty Publications

No abstract provided.

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Conical Intersection And Potential Energy Surface Features Of A Model Retinal Chromophore: Comparison Of Eom-Cc And Multireference Methods, Samer Gozem, Anna I. Krylov, Massimo Olivucci Jan 2013

Conical Intersection And Potential Energy Surface Features Of A Model Retinal Chromophore: Comparison Of Eom-Cc And Multireference Methods, Samer Gozem, Anna I. Krylov, Massimo Olivucci

Chemistry Faculty Publications

This work investigates the performance of equation-of-motion coupled-cluster (EOM-CC) methods for describing the changes in the potential energy surfaces of the penta-2,4-dieniminium cation, a reduced model of the retinal chromophore of visual pigments, due to dynamical electron correlation effects. The ground-state wave function of this model includes charge-transfer and diradical configurations whose weights vary along different displacements and are rapidly changing at the conical intersection between the ground and the first excited states, making the shape of the potential energy surface sensitive to a balanced description of nondynamical and dynamical correlation. Recently, variational (MRCISD) and perturbative (MRPT2) approaches for including …

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Test Selection On Extended Finite State Machines With Provable Guarantees, Bo Guo, Mahadevan Subramaniam Jan 2013

Test Selection On Extended Finite State Machines With Provable Guarantees, Bo Guo, Mahadevan Subramaniam

Chemistry Faculty Publications

Building high confidence regression test suites to validate new system versions is a challenging problem. A model- based approach to build a regression test suite from a given test suite is described. The generated test suite includes every test that will traverse a change performed to produce the new version, and consists of only such tests to reduce the testing costs. Finite state machines extended with typed variables (EFSMs) are used to model systems and system changes are mapped to EFSM transition changes adding/deleting/replacing EFSM transitions and states. Tests are a sequence of input and expected output messages with concrete …

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Lomustine Analogous Drug Structures For Intervention Of Brain And Spinal Cord Tumors: The Benefit Of In Silico Substructure Search And Analysis, Ronald Bartzatt Jan 2013

Lomustine Analogous Drug Structures For Intervention Of Brain And Spinal Cord Tumors: The Benefit Of In Silico Substructure Search And Analysis, Ronald Bartzatt

Chemistry Faculty Publications

Lomustine is a nitrosourea anticancer agent shown to be effective for treatment of childhood medulloblastoma. In silico substructure searches produced 17 novel nitrosourea agents analogous to lumustine and retaining activity for DNA alkylation and cytotoxic activity. The mean values for Log P, polar surface area, formula weight, number of oxygens & nitrogens, and rotatable bonds were 2.524, 62.89 Anstroms2, 232.8, 5, and 2, respectively. All 17 agents have formula weight less than 450 and Log P less than 5, two criteria preferred for blood-brain barrier penetration.These agents have a polar surface area less than 90 Angstroms2. Each show zero violations …

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Reaction Between Polyol-Esters And Phosphate Esters In The Presence Of Metal Carbides, David W. Johnson, Carolyn Iacullo, John E. Hils Jan 2013

Reaction Between Polyol-Esters And Phosphate Esters In The Presence Of Metal Carbides, David W. Johnson, Carolyn Iacullo, John E. Hils

Chemistry Faculty Publications

The reaction of metal carbides with polyol esters found in aerospace lubricants and phosphate esters commonly used as additives was investigated. Carbides were of particular interest since modern materials under consideration at high temperature bearings have surfaces that are primarily metal carbides. Vanadium and chromium carbide were found to react with the ester and phosphate ester by a transesterification reaction, producing an alkyl phosphate which is less stable than the aromatic phosphate esters. In the process, the metal carbide is converted to the metal phosphate and metal polyphosphate, evidenced by the infrared and Raman spectra of the solid residue and …

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