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Articles 301 - 330 of 402

Full-Text Articles in Chemistry

A Green Chemoselective And Practical Approach Toward N-(2-Azetidinonyl) 25-Disubstituted Pyrroles, Debasish Bandyopadhyay, Elvira Rhodes, Bimal K. Banik Oct 2013

A Green Chemoselective And Practical Approach Toward N-(2-Azetidinonyl) 25-Disubstituted Pyrroles, Debasish Bandyopadhyay, Elvira Rhodes, Bimal K. Banik

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

Pyrrole and 2-azetidinone are two essential heterocyclic scaffolds, which are being broadly used in medicinal chemistry and drug discovery field. A green and practical method to synthesize novel N-(2-azetidinonyl) 2,5-disubstituted pyrroles, which are comprised of both pyrrole and 2-azetidinone moieties, has been developed. The classical Paal–Knorr reaction is one of the simplest and most economical methods for the synthesis of biologically important and pharmacologically useful pyrrole derivatives. The present procedure for the synthesis of N-(2-azetidinonyl) 2,5-disubstituted pyrroles (1,2,5-trisubstituted pyrroles) has been accomplished by reacting 3-amino β-lactams and 2,5-hexanedione in the presence of bismuth nitrate pentahydrate as an ecofriendly …


Derivative Couplings And Analytic Gradients For Diabatic States, With An Implementation For Boys-Localized Configuration-Interaction Singles, Shervin Fatehi, Ethan Alguire, Joseph Subotnik Sep 2013

Derivative Couplings And Analytic Gradients For Diabatic States, With An Implementation For Boys-Localized Configuration-Interaction Singles, Shervin Fatehi, Ethan Alguire, Joseph Subotnik

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

We demonstrate that Boys-localized diabatic states do indeed exhibit small derivative couplings, as is required of quasidiabatic states. In doing so, we present a general formalism for calculating derivative couplings and analytic gradients for diabatic states. We then develop additional equations specific to the case of Boys-localized configuration-interaction singles (CIS)—in particular, the analytic gradient of the CIS dipole matrix—and we validate our implementation against finite-difference results. In a forthcoming paper, we will publish additional algorithmic and computational details and apply our method to the Closs energy-transfer systems as a further test of the validity of Boys-localized diabatic states.


Cloning And Characterization Of Ef-Tu And Ef-Ts From Pseudomonas Aeruginosa, Stephanie O. Palmer, Edna Y. Rangel, Alberto E. Montalvo, Alexis T. Tran, Kate C. Ferguson, James M. Bullard Sep 2013

Cloning And Characterization Of Ef-Tu And Ef-Ts From Pseudomonas Aeruginosa, Stephanie O. Palmer, Edna Y. Rangel, Alberto E. Montalvo, Alexis T. Tran, Kate C. Ferguson, James M. Bullard

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

We have cloned genes encoding elongation factors We have cloned genes encoding elongation factors EF-Tu and EF-Ts from Pseudomonas aeruginosa and expressed and purified the proteins to greater than 95% homogeneity. Sequence analysis indicated that P. aeruginosa EF-Tu and EF-Ts are 84% and 55% identical to E. coli counterparts, respectively. P. aeruginosa EF-Tu was active when assayed in GDP exchange assays. Kinetic parameters for the interaction of EF-Tu with GDP in the absence of EF-Ts were observed to be = 33 μM, = 0.003 s−1, and the specificity constant was  s−1 μM−1. In the presence of EF-Ts, these values were …


Facile, Green Synthesis Of Large Single Crystal Copper Micro And Nanoparticles With Ascorbic Acid And Gum Arabic, Preston B. Landon, Alexander H. Mo, Carlos T. Ramos, Jose J. Gutierrez, Ratnesh Lal Sep 2013

Facile, Green Synthesis Of Large Single Crystal Copper Micro And Nanoparticles With Ascorbic Acid And Gum Arabic, Preston B. Landon, Alexander H. Mo, Carlos T. Ramos, Jose J. Gutierrez, Ratnesh Lal

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

Large single crystal colloidal copper particles with diameters between 0.5 - 2 μm were created using a green synthesis process. The process used ascorbic acid to reduce Schweizer’s reagent created in situ using copper salts in the presence of various concentrations of gum arabic. The Schweizer’s reagents were created by varying the concentrations of ammonium hydroxide and copper nitrate solutions, copper hydroxide, or copper sulfate. The pH of the solution was controlled by the addition of ascorbic acid. Particle formation was favored at high temperature using copper sulfate at pH values ranging from 7.5 to 9, while the optimal formation …


Study Of The Thermodynamics Of Chromium(Iii) And Chromium(Vi) Binding To Iron(Ii/Iii)Oxide Or Magnetite Or Ferrite And Magnanese(Ii) Iron (Iii) Oxide Or Jacobsite Or Manganese Ferrite Nanoparticles, Steven Luther, Nathan Brogfeld, Jisoo Kim, Jason Parsons Jun 2013

Study Of The Thermodynamics Of Chromium(Iii) And Chromium(Vi) Binding To Iron(Ii/Iii)Oxide Or Magnetite Or Ferrite And Magnanese(Ii) Iron (Iii) Oxide Or Jacobsite Or Manganese Ferrite Nanoparticles, Steven Luther, Nathan Brogfeld, Jisoo Kim, Jason Parsons

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

Removal of chromium(III) or (VI) from aqueous solution was achieved using Fe3O4, and MnFe2O4 nanomaterials. The nanomaterials were synthesized using a precipitation method and characterized using XRD. The size of the nanomaterials was determined to be 22.4±0.9 nm (Fe3O4) and 15.5±0.5 nm (MnFe2O4). The optimal binding pH for chromium(III) and chromium(VI) were pH 6 and pH 3. Isotherm studies were performed, under light and dark conditions, to determine the capacity of the nanomaterials. The capacities for the light studies with MnFe2O4 and Fe3O4 were determined to be 7.189 and 10.63 mg/g, respectively, for chromium(III). The capacities for the light studies …


I. Norbornene As Organocatalyst: Unusual: Amination Ii. Stereoselective Synthesis Of 3, 4 Di-Substituted Β-Lactams; Classical Vs Microwave Method, Ravi Reddaboyna May 2013

I. Norbornene As Organocatalyst: Unusual: Amination Ii. Stereoselective Synthesis Of 3, 4 Di-Substituted Β-Lactams; Classical Vs Microwave Method, Ravi Reddaboyna

Theses and Dissertations - UTB/UTPA

I. Amine functionality is important in the preparation of biologically active and industrially useful molecules. Many approaches to form C―N bonds provide access to fine chemical building blocks, pharmaceuticals, agrochemicals, and surfactants. Microwave irradiation is a highly recommended ecofriendly approach for the synthesis of medicinally important compounds. Organic catalysis is important segment in the field of organic chemistry, for the synthesis of many complex molecules by providing a number of advantages.

II. Cancer refers to a large group of diseases characterized by uncontrolled cell multiplication and the ability of these cells to enter other tissues and spread to other parts …


Electrospinning Nanofibers For Controlled Drug Release, Indrani Banik May 2013

Electrospinning Nanofibers For Controlled Drug Release, Indrani Banik

Theses and Dissertations - UTB/UTPA

Electrospinning is the most widely studied technique for the synthesis of nanofibers. Electrospinning is considered as one of the technologies that can produce nanosized drugs incorporated in polymeric nanofibers. In vitro and in vivo studies have demonstrated that the release rates of drugs from these nanofiber formulations are enhanced compared to those from original drug substance. This technology has the potential for enhancing the oral delivery of poorly soluble drugs [1]. The electrospun mats were made using Polycaprolactone/PCL, Poly(DL-lactide)/PDL 05 and Poly(DL-lactide-co-glycolide)/PLGA. The drugs incorporated in the electrospun fibers were 5-Fluorouracil and Rapamycin. The evidence of the drugs being embedded …


Novel Patterns Of Torsion-Inversion-Rotation Energy Levels In The Ν11 Asymmetric Ch-Stretch Spectrum Of Methylamine, Mahesh B. Dawadi, C. Michael Lindsay, Andrei Chirokolava, David S. Perry, Li Hong Xu Mar 2013

Novel Patterns Of Torsion-Inversion-Rotation Energy Levels In The Ν11 Asymmetric Ch-Stretch Spectrum Of Methylamine, Mahesh B. Dawadi, C. Michael Lindsay, Andrei Chirokolava, David S. Perry, Li Hong Xu

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

The high-resolution infrared spectrum of methylamine (CH3NH2) has been recorded using slit-jet direct absorption spectroscopy in the ν11 CH-stretch region (2965–3005 cm−1) with a resolution of 0.0025 cm−1. The 621 lines assigned by ground state combination differences represent 27 substates with |K| ≤ 2 for the A, B, E1, and E2 symmetries. The spectrum of CH3NH2 is complicated by torsion and inversion tunneling connecting six equivalent minima. The upper states K = 0, ± 1 for E1 and E2 are substantially perturbed by “dark” states. The result in the spectrum is multiplets of 2 or 3 …


Evaluation Of Single Electron Transfer Reduction Products Of 3-Oxoindoles As Antibacterial Agents, Debasish Bandyopadhyay, Irani Biswas, Subrata Laskar, Bidyut Basak Jan 2013

Evaluation Of Single Electron Transfer Reduction Products Of 3-Oxoindoles As Antibacterial Agents, Debasish Bandyopadhyay, Irani Biswas, Subrata Laskar, Bidyut Basak

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

Objective: The objective of the present study is to assess the antibacterial properties of six indole derivatives viz, 3-(Naphth-1-y - methyl) –indole (II), 3-(1-Naphthylcarbonyl – indole (III), 3,3' –diformyl-2,2' –bis indole (IV), 1,4- (3,3' –di indolyl) – 1,4-dioxobutane (V), 3-benzoyl indole (VI) and 1,1 – bis – (3-indolyl)- ethane (VII) synthesized by single electron transfer reduction of 3-formylindole (I) against two Gram +ve and two Gram –ve bacteria which usually cause human infections.

Methods: Synthesis of 3-formyl indole from which the indole derivatives were prepared were further characterized by IR and NMR analysis. The six synthesized compounds were screened for …


Facile Molten-Salt Synthesis Of Double Perovskite La2bmno 6 Nanoparticles, Yuanbing Mao Dec 2012

Facile Molten-Salt Synthesis Of Double Perovskite La2bmno 6 Nanoparticles, Yuanbing Mao

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

Crystalline double perovskite La2BMnO6 (B = Ni and Co) nanoparticles with an average grain size of ∼64 nm were successfully prepared using a facile, environmentally friendly, scalable molten-salt reaction at 700 °C in air. Their composition and structural and magnetic properties have been characterized.


Synthesis And Luminescence Properties Of Core-Shell Structured (Lanthanum(1-X)Europium(X))(2)Zirconium Heptoxid[At]Yttrium Orthoborate Spherical Nanoparticles, Suresh Babu Alaparthi Dec 2012

Synthesis And Luminescence Properties Of Core-Shell Structured (Lanthanum(1-X)Europium(X))(2)Zirconium Heptoxid[At]Yttrium Orthoborate Spherical Nanoparticles, Suresh Babu Alaparthi

Theses and Dissertations - UTB/UTPA

Many rare earth compounds have photoluminescent characteristics for various important applications. In this study, europium doped La2Zr2O7 nanoparticles were first synthesized morphology-controllably by using a molten-salt synthesis method. These nanoparticles were used as the core for coating with YBO3 shell. We then explored the effect of different experimental processing parameters, such as annealing temperatures, reaction times and different ratios of salt mixtures on the structure and morphology of these nanoparticles. The overall core size and shell thickness can be controlled by varying the reactant concentration both the core and shell material. These core@shell nanoparticles were then characterized mainly using power …


Titanium Dioxide Nanofibers And Microparticles Containing Nickel Nanoparticles, Faheem A. Sheikh, Javier Macossay-Torres, M. A. Kanjwal, Abdalla Abdal-Hay, Mudasir A. Tantry, Hern Kim Nov 2012

Titanium Dioxide Nanofibers And Microparticles Containing Nickel Nanoparticles, Faheem A. Sheikh, Javier Macossay-Torres, M. A. Kanjwal, Abdalla Abdal-Hay, Mudasir A. Tantry, Hern Kim

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

The present study reports on the introduction of various nanocatalysts containing nickel (Ni) nanoparticles (NPs) embedded within TiO2 nanofibers and TiO2 microparticles. Typically, a sol-gel consisting of titanium isopropoxide and Ni NPs was prepared to produce TiO2 nanofibers by the electrospinning process. Similarly, TiO2 microparticles containing Ni were prepared using a sol-gel syntheses process. The resultant structures were studied by SEM analyses, which confirmed well-obtained nanofibers and microparticles. Further, the XRD results demonstrated the crystalline feature of both TiO2 and Ni in the obtained composites. Internal morphology of prepared nanofibers and microparticles containing Ni NPs was characterized by TEM, which …


An Expeditious Iodine-Catalyzed Synthesis Of 3-Pyrrole-Substituted 2-Azetidinones, Debasish Bandyopadhyay, Jessica Cruz, Ram N. Yadav, Bimal K. Banik Oct 2012

An Expeditious Iodine-Catalyzed Synthesis Of 3-Pyrrole-Substituted 2-Azetidinones, Debasish Bandyopadhyay, Jessica Cruz, Ram N. Yadav, Bimal K. Banik

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

2-Azetidinones and pyrroles are two highly important classes of molecules in organic and medicinal chemistry. A green and practical method for the synthesis of 3-pyrrole-substituted 2-azetidinones using catalytic amounts of molecular iodine under microwave irradiation has been developed. Following this method, a series of 3-pyrrole-substituted 2-azetidinones have been synthesized with a variety of substituents at N-1 and at C-4. The procedure is equally effective for mono-as well as polyaromatic groups at the N-1 position of the 2-azetidinone ring. The C-4 substituent has no influence either on the yield or the rate of the reaction. Optically pure 3-pyrrole-substituted 2-azetidinones have also …


Cop1 Mediates The Coordination Of Root And Shoot Growth By Light Through Modulation Of Pin1- And Pin2-Dependent Auxin Transport In Arabidopsis, Massimiliano Sassi, Yanfen Lu, Yonghong Zhang, Juan Wang, Pankaj Dhonukshe, Ikram Blilou, Minqiu Dai, Juan Li, Ximing Gong, Yvon Jaillais, Xuhong Yu, Jan Traas, Ida Ruberti, Haiyang Wang, Ben Scheres, Teva Vernoux, Jian Xu Sep 2012

Cop1 Mediates The Coordination Of Root And Shoot Growth By Light Through Modulation Of Pin1- And Pin2-Dependent Auxin Transport In Arabidopsis, Massimiliano Sassi, Yanfen Lu, Yonghong Zhang, Juan Wang, Pankaj Dhonukshe, Ikram Blilou, Minqiu Dai, Juan Li, Ximing Gong, Yvon Jaillais, Xuhong Yu, Jan Traas, Ida Ruberti, Haiyang Wang, Ben Scheres, Teva Vernoux, Jian Xu

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

When a plant germinates in the soil, elongation of stem-like organs is enhanced whereas leaf and root growth is inhibited. How these differential growth responses are orchestrated by light and integrated at the organismal level to shape the plant remains to be elucidated. Here, we show that light signals through the master photomorphogenesis repressor COP1 to coordinate root and shoot growth in Arabidopsis. In the shoot, COP1 regulates shoot-to-root auxin transport by controlling the transcription of the auxin efflux carrier gene PIN-FORMED1 (PIN1), thus appropriately tuning shoot-derived auxin levels in the root. This in turn directly influences root elongation and …


Electrospun Biocompatible Polyurethanes With The Addition Of Multi-Walled Carbon Nanotubes, Travis Cantu Aug 2012

Electrospun Biocompatible Polyurethanes With The Addition Of Multi-Walled Carbon Nanotubes, Travis Cantu

Theses and Dissertations - UTB/UTPA

Three different Polyurethanes (PUs) Lycra®, HydroThaneTM, and BioSpan®, were electrospun and characterized using Scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform-infrared spectroscopy (FTIR), & Raman spectroscopy. Nanofiber composites were made by incorporating MWCNTs at three different concentration 0.1wt% 0.5wt% and 1.0wt% to the three PUs. These samples were characterized and mechanical and thermal test were done. The TEM images showed MWCNT bundling in the polymer matrix at the highest concentration, the FTIR showed shifts in characteristic urethane bands indicating an interaction with the polymer and MWCNTs. Mechanical test showed a decrease in the Young’s modulus (E’) in most …


Synthesis And Characterization Of Biodegradable Electrospun Polyurethanes For Biomedical Applications, Xujun Zhang Aug 2012

Synthesis And Characterization Of Biodegradable Electrospun Polyurethanes For Biomedical Applications, Xujun Zhang

Theses and Dissertations - UTB/UTPA

Two types of polyesters [(Poly(ε-caprolactone) and Poly(δ-valerolactone)] were synthesized by ring-opening polymerization with diethylene glycol as a initiator and stannous octate as a catalyst. The corresponding polyurethanes were synthesized by two-step polymerization with 1,4-diisocyanate butane (BDI) and reacted with 1,4-diamino butane (Putrescine) chain extender. The polymers were characterized by Proton Nuclear Magnetic Resonance (1H NMR), Fourier Transform Infrared Spectroscopy (FT-IR), Raman Spectroscopy, Size-exclusive Chromatography (SEC), Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). The resulting polyurethanes were fabricated into nanofibers using an electrospinning technique. The morphological, structural characterizations and thermal properties of the bulk polyurethanes and electrospun polyurethanes nanofibers were …


Synthesis Of Novel Bis-Β-Lactams, Jocabed Marquez Aug 2012

Synthesis Of Novel Bis-Β-Lactams, Jocabed Marquez

Theses and Dissertations - UTB/UTPA

This study presents the synthesis and structure of newly discovered β-lactams and the mechanism of their synthesis via the Staudinger reaction. β-lactams known as 2-azetidinones, are four membered cyclic amides that have been extensively used and recognized as the central motif of the β-lactam antibiotics, the most widely employed family of antimicrobial agent to date. The Staudinger reaction involves the cycloaddition between an acid chloride with an imine, in presence of a tertiary base. The possibility of cooperative effects from two therapeutic functionalities in drug molecules, has prompted interest in the synthesis of Bis-β-lactams. The synthesis of 2 novel Bis-β-lactams …


Microwave-Induced Bismuth Nitrate-Catalyzed Multicomponent Reaction Toward Heterocycles, Ashwini Bobbala Aug 2012

Microwave-Induced Bismuth Nitrate-Catalyzed Multicomponent Reaction Toward Heterocycles, Ashwini Bobbala

Theses and Dissertations - UTB/UTPA

The microwave-induced reaction for the synthesis of nitrogen containing heterocyclesis very important in medicinal chemistry. The synthesis of various other valuable compounds is also done by employing this reaction. The aza Diels-Alder reaction is one of the most powerful synthetic tools for the synthesis of nitrogen containing heterocycles. The main goal of the research is to synthesize the nitrogen containing heterocycles using Bismuth nitrate as the catalyst in the presence of microwave irradiation. In the present study we explore the catalytic activity of bismuth nitrate and the role of microwave reactor in the synthesis of 2, 3-diaryl substituted bicyclic octanone …


Derivative Couplings With Built-In Electron-Translation Factors: Application To Benzene, Shervin Fatehi, Joseph E. Subotnik Jul 2012

Derivative Couplings With Built-In Electron-Translation Factors: Application To Benzene, Shervin Fatehi, Joseph E. Subotnik

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

Derivative couplings are the essential quantities at the interface between electronic-structure calculations and nonadiabatic dynamics. Unfortunately, standard approaches for calculating these couplings usually neglect electronic motion, which can lead to spurious electronic transitions. Here we provide a general framework for correcting these anomalies by incorporating perturbative electron-translation factors (ETFs) into the atomic-orbital basis. For a range of representative organic molecules, we find that our ETF correction is often small but can be qualitatively important, especially for few-atom systems or highly symmetric molecules. Our method entails no additional computational cost, such that ETFs are “built-in,” and it is equivalent to a …


Microwave-Assisted Polystyrene Sulfonatecatalyzed Synthesis Of Novel Pyrroles, Rosario Astrid Vargas Cardenas, Blanca Olinda Quintanilla Leal, Ashwini Reddy, Debasish Bandyopadhyay, Bimal K. Banik Jun 2012

Microwave-Assisted Polystyrene Sulfonatecatalyzed Synthesis Of Novel Pyrroles, Rosario Astrid Vargas Cardenas, Blanca Olinda Quintanilla Leal, Ashwini Reddy, Debasish Bandyopadhyay, Bimal K. Banik

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

Background: Pyrroles are widely distributed in nature and important biologically active molecules. The reaction of amines with 2,5-dimethoxytetrahydrofuran is a promising pathway for the synthesis of pharmacologically active pyrroles under microwave irradiation.

Results: Microwave-induced polystyrenesulfonate-catalyzed synthesis of pyrroles from amines and 2,5- diemthoxytetrahydrofuran has been accomplished with excellent yield. This method produces pyrroles with polyaromatic amines.

Conclusion: The present procedure for the synthesis of N-aromatic substituted pyrroles will find useful application in the area of pharmacologically active molecules.


Nanoenergetic Composite Based On I2o5/Al For Biological Agent Defeat, Mkhitar Hobosyan, Alexander V. Kazanksy, Karen S. Martirosyan Jun 2012

Nanoenergetic Composite Based On I2o5/Al For Biological Agent Defeat, Mkhitar Hobosyan, Alexander V. Kazanksy, Karen S. Martirosyan

Physics & Astronomy Faculty Publications

The risk of bioterrorism events involving the intentional airborne release of contagious agents has led to development of new approaches for bio agent defeat technologies both indoors and outdoors. This report describes nanoenergetic gas generators (NGG) system that exhibit long term stability and superior release of biocidal substances for destruction of pathogenic bacteria. The effect of iodine vaporization on destroying of Escherichia coli (E-coli, HB101 K-12 strain) by using expressing Green Fluorescent Protein (GFP) was investigated. HB101 K-12 has been genetically modified to prevent its growth unless grown on an enriched medium. To obtain quantitative data we used pGLO transformation …


Identifying Risk Factors For Disparities In Breast Cancer Mortality Among African-American And Hispanic Women, Nancy Tian, Pierre Goovaerts, T. Benjamin Zhan, T. Edwin Chow, J. Gaines Wilson Jun 2012

Identifying Risk Factors For Disparities In Breast Cancer Mortality Among African-American And Hispanic Women, Nancy Tian, Pierre Goovaerts, T. Benjamin Zhan, T. Edwin Chow, J. Gaines Wilson

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

Background: This study evaluated the risk factors associated with racial disparities in female breast cancer mortality for African-American and Hispanic women at the census tract level in Texas from 1995 to 2005.

Methods: Data on female breast cancer cases were obtained from the Texas Cancer Registry. Socioeconomic and demographic data were collected from Census 2000. Network distance and driving times to mammography facilities were estimated using Geographic Information System techniques. Demographic, poverty and spatial accessibility factors were constructed using principal component analysis. Logistic regression models were developed to predict the census tracts with significant racial disparities in breast cancer mortality …


Development Of An Assay To Screen For Novel Proteins From Bacillus Thuringiensis With Antibacterial Activity, Auriole T. Tamegnon May 2012

Development Of An Assay To Screen For Novel Proteins From Bacillus Thuringiensis With Antibacterial Activity, Auriole T. Tamegnon

Theses and Dissertations - UTB/UTPA

Bacillus thuringiensis (Bt) produces the non specific Cyt protein and the specific Cry protein. Past research has shown these proteins are toxic to insects, red blood cells, cancer cells, and some bacteria. While many antibacterial substances are known to exist, efforts to find new ones still continue. In this project we used Bt 6-2-56 (containing a novel filament associated parasporal body which appears non-toxic to insects and protozoan) and Bt 4Q13 (which has been shown to have activity against E. coli and S. aureus) to develop a simple, easy, scalable assay in a 96 well Microtitre plate to look for …


Communication: Adjusting Charge Transfer State Energies For Configuration Interaction Singles: Without Any Parameterization And With Minimal Cost, Xinle Liu, Shervin Fatehi, Yihan Shao, Brad S. Veldkamp, Joseph Subotnik Apr 2012

Communication: Adjusting Charge Transfer State Energies For Configuration Interaction Singles: Without Any Parameterization And With Minimal Cost, Xinle Liu, Shervin Fatehi, Yihan Shao, Brad S. Veldkamp, Joseph Subotnik

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

In a recent article, we showed that configuration interaction singles (CIS) has a systematic bias against charge-transfer (CT) states: CT vertical excitation energies are consistently too high (by 1-2 eV) as compared with non-CT energies [J. E. Subotnik, J. Chem. Phys. 137, 071104 (2011)]. We now show that this CIS error can be corrected approximately by performing a single Newton- Raphson step to reoptimize orbitals, thus establishing a new set of orbitals which better balances ground and excited state energies. The computational cost of this correction is exactly that of one coupled-perturbed Hartree-Fock calculation, which is effectively the cost of …


Sorption Kinetic Study Of Selenite And Selenate Onto A High And Low Pressure Aged Iron Oxide Nanomaterial, Christina M. Gonzalez, Jeffrey Hernandez, Jose R. Peralta-Videa, Cristian E. Botez, Jason Parsons, Jorge L. Gardea-Torresdey Apr 2012

Sorption Kinetic Study Of Selenite And Selenate Onto A High And Low Pressure Aged Iron Oxide Nanomaterial, Christina M. Gonzalez, Jeffrey Hernandez, Jose R. Peralta-Videa, Cristian E. Botez, Jason Parsons, Jorge L. Gardea-Torresdey

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

The sorption of selenite (SeO32−) and selenate (SeO42−) onto Fe3O4 nanomaterials produced by non microwave-assisted or microwave-assisted synthetic techniques was investigated through use of the batch technique. The phase of both synthetic nanomaterials was determined to be magnetite by X-ray diffraction. The average grain sizes of non microwave-assisted and microwave-assisted synthetic Fe3O4 were determined to be 27 and 25 nm, respectively through use of the Scherrer's equation. Sorption of selenite was pH independent in the pH range of 2-6, while sorption of selenate decreased at pH 5 and 6. The addition of Cl− had no significant effect on selenite or …


Polystyrenesulfonate-Catalyzed Synthesis Of Novel Pyrroles Through Paal-Knorr Reaction, Mandira Banik, Bianca Ramirez, Ashwini Reddy, Debasish Bandyopadhyay, Bimal K. Banik Mar 2012

Polystyrenesulfonate-Catalyzed Synthesis Of Novel Pyrroles Through Paal-Knorr Reaction, Mandira Banik, Bianca Ramirez, Ashwini Reddy, Debasish Bandyopadhyay, Bimal K. Banik

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

Background: The classical Paal-Knorr reaction is one of the simplest and most economical methods for the synthesis of biologically important and pharmacologically useful pyrrole derivatives.

Results: Polystyrenesulfonate-catalyzed simple synthesis of substituted pyrroles following Paal-Knorr reaction has been accomplished with an excellent yield in aqueous solution. This method also produces pyrroles with multicyclic polyaromatic amines.

Conclusions: The present procedure for the synthesis of N-polyaromatic substituted pyrroles will find application in the synthesis of potent biologically active molecules.


Structural Basis For Ca 2+-Induced Activation And Dimerization Of Estrogen Receptor Alpha By Calmodulin, Yonghong Zhang, Zhigang Li, David B. Sacks, James B. Ames Mar 2012

Structural Basis For Ca 2+-Induced Activation And Dimerization Of Estrogen Receptor Alpha By Calmodulin, Yonghong Zhang, Zhigang Li, David B. Sacks, James B. Ames

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

The estrogen receptor α (ER-α) regulates expression of target genes implicated in development, metabolism, and breast cancer. Calcium-dependent regulation of ER-α is critical for activating gene expression and is controlled by calmodulin (CaM). Here, we present the NMR structures for the two lobes of CaM each bound to a localized region of ER-α (residues 287–305). A model of the complete CaM·ER-α complex was constructed by combining these two structures with additional data. The two lobes of CaM both compete for binding at the same site on ER-α (residues 292, 296, 299, 302, and 303), which explains why full-length CaM binds …


A Microwave-Assisted Bismuth Nitrate-Catalyzed Unique Route Toward 1,4-Dihydropyridines, Debasish Bandyopadhyay, Stephanie Maldonado, Bimal K. Banik Mar 2012

A Microwave-Assisted Bismuth Nitrate-Catalyzed Unique Route Toward 1,4-Dihydropyridines, Debasish Bandyopadhyay, Stephanie Maldonado, Bimal K. Banik

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

The classical Hantzsch reaction is one of the simplest and most economical methods for the synthesis of biologically important and pharmacologically useful 1,4-dihydropyridine derivatives. Bismuth nitrate pentahydrate under microwave irradiation is proven to act as a very efficient catalyst for a one-pot, three-component synthesis of 1,4-dihydropyridines in excellent yields from diverse amines/ammonium acetate, aldehydes and 1,3-dicarbonyl compounds within 1-3 min under solvent-free conditions. The present environmentally benign procedure for the synthesis of 1,4-dihydropyridines is suitable for library synthesis and it will find application in the synthesis of potent biologically active molecules. The excellent yield and extreme rapidity of the method …


A Simple Approach For Synthesis, Characterization And Bioactivity Of Bovine Bones To Fabricate The Polyurethane Nanofiber Containing Hydroxyapatite Nanoparticles, Faheem A. Sheikh, M. A. Kanjwal, Javier Macossay-Torres, N. A. M. Barakat, H. Y. Kim Jan 2012

A Simple Approach For Synthesis, Characterization And Bioactivity Of Bovine Bones To Fabricate The Polyurethane Nanofiber Containing Hydroxyapatite Nanoparticles, Faheem A. Sheikh, M. A. Kanjwal, Javier Macossay-Torres, N. A. M. Barakat, H. Y. Kim

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

In the present study, we had introduced polyurethane (PU) nanofibers that contain hydroxyapatite (HAp) nanoparticles (NPs) as a result of an electrospinning process. A simple method that does not depend on additional foreign chemicals had been employed to synthesize HAp NPs through the calcination of bovine bones. Typically, a colloidal gel consisting of HAp/PU had been electrospun to form nanofibers. In this communication, physiochemical aspects of prepared nanofibers were characterized by FE-SEM, TEM and TEM-EDS, which confirmed that nanofibers were well-oriented and good dispersion of HAp NPs, over the prepared nanofibers. Parameters, affecting the utilization of the prepared nanofibers in …


Bismuth Nitrate-Induced Microwave-Assisted Expeditious Synthesis Of Vanillin From Curcumin, Debasish Bandyopadhyay, Bimal K. Banik Jan 2012

Bismuth Nitrate-Induced Microwave-Assisted Expeditious Synthesis Of Vanillin From Curcumin, Debasish Bandyopadhyay, Bimal K. Banik

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

Background: Curcumin and vanillin are the two useful compounds in food and medicine. Bismuth nitrate pentahydrate is an economical and ecofriendly reagent.

Method: Bismuth nitrate pentahydrate impregnated montmorillonite KSF clay and curcumin were subjected to microwave irradiation.

Results: Microwave-induced bismuth nitrate-promoted synthesis of vanillin from curcumin has been accomplished in good yield under solvent-free condition. Twenty-five different reaction conditions have been studied to optimize the process.

Conclusion: The present procedure for the synthesis of vanillin may find useful application in the area of industrial process development.