Chemistry Commons^™

Ultrasound-Assisted Aza-Michael Reaction In Water: A Green Procedure, Debasish Bandyopadhyay, Sanghamitra Mukherjee, Luis C. Turrubiartes, Bimal K. Banik

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

The conjugate addition of amines to conjugated alkenes (commonly known as aza-Michael reaction) constitutes a key step for the synthesis of various complex natural products, antibiotics, α-amino alcohols and chiral auxiliaries. Ultrasound-induced addition of several amines to α, β-unsaturated ketones, esters and nitriles has been carried out very efficiently in water as well as under solvent-free conditions. No catalysts or solid supports have been used in this method. Remarkable enhancement of reaction rate has been observed in water under ultrasound-induced method. This environmentally benign procedure has provided clean formation of the products with better selectivity.

Analytic Derivative Couplings Between Configuration-Interaction-Singles States With Built-In Electron-Translation Factors For Translational Invariance, Shervin Fatehi, Ethan Alguire, Yihan Shao, Joseph Subotnik

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

We present a method for analytically calculating the derivative couplings between a pair of configuration-interaction-singles (CIS) excited states obtained in an atom-centered basis. Our theory is exact and has been derived using two completely independent approaches: one inspired by the Hellmann-Feynman theorem and the other following from direct differentiation. (The former is new, while the latter is in the spirit of existing approaches in the literature.) Our expression for the derivative couplings incorporates all Pulay effects associated with the use of an atom-centered basis, and the computational cost is minimal, roughly comparable to that of a single CIS energy gradient. …

Fabrication Of Mineralized Collagen From Bovine Waste Materials By Hydrothermal Method As Promised Biomaterials, Faheem A. Sheikh, M. A. Kanjwal, Javier Macossay-Torres, Muneeb A. Muhammad, Travis Cantu, Ioannis S. Chronakis, N. A. M. Barakat, Hak Yong Kim

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

In the present study, we aimed to produce mineralized-collagen by hydrothermal process. A simple method not depending on additional foreign chemicals has been employed to isolate the mineralized-collagen fibers from bovine waste. The process of extraction involves the use of hydrothermal method from available bovine bones. The structural and morphological properties of the collagen fibers were characterized by using scanning electron microscopy and transmission electron microscopy. These results indicated well received collagen fibers, having a diameter less than 1 μm and with established mineral content in the individual fibers. The X-ray diffraction showed the crystalline feature of the obtained nano-compounds. …

Polycyclic Aromatic Compounds As Anticancer Agents: Evaluation Of Synthesis And In Vitro Cytotoxicity, Debasish Bandyopadhyay, Jose C. Granados, John D. Short, Bimal K. Banik

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

Polycyclic aromatic hydrocarbons (PAHs) are considered to be significant environmental carcinogens. Additionally, various planar ring systems are capable of intercalating with DNA, leading to a number of drugs that possess chemotherapeutic activity. In this study, three new polyaromatic compounds with a side chain were synthesized, and spectroscopic as well as elemental analyses were performed. The addition of the long chains to either chrysene or pyrene caused a red-shift in the spectral emission when compared to the corresponding polycyclic aromatic hydrocarbons itself. Furthermore, the cytotoxicity of the three novel polyaromatic compounds was evaluated in vitro in a panel of cultured mammalian …

A Truly Green Synthesis Of A-Aminonitriles Via Strecker Reaction, Debasish Bandyopadhyay, Juliana M. Velazquez, Bimal K. Banik

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

Background: The classical Strecker reaction is one of the simplest and most economical methods for the synthesis of racemic a-aminonitriles (precursor of a-amino acids) and pharmacologically useful compounds.

Results: Indium powder in water is shown to act as a very efficient catalyst for one-pot, three-component synthesis of a-aminonitriles from diverse amines, aldehydes and TMSCN. This general rapid method is applicable to a wide range of amines and aldehydes and produces products in excellent yield.

Conclusions: The present one-pot, three-component environmentally benign procedure for the synthesis of aaminonitriles will find application in the synthesis of complex biologically active molecules.

Bismuth Nitrate Pentahydrate-Induced Novel Nitration Of Eugenol, Luis Canales, Debasish Bandyopadhyay, Bimal K. Banik

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

Background: Eugenol, the main constituent of clove oil possesses a number of medicinal activities. To enhance the medicinal property, structural modification is required. On the other hand, bismuth nitrate pentahydrate has been established as an excellent eco-friendly nitrating agent for several classes of organic compounds.

Results: Bismuth nitrate pentahydrate-induced nitration of eugenol has been investigated very thoroughly. Twenty five different conditions have been studied. The microwave-induced solvent-free reaction has been identified as the best condition.

Conclusions: Spectral analyses confirm that 5-nitroeugenol is the sole product in all the cases. No oxidized or isomerized product could be detected.

Creation Of Post Ap Chemistry Class, Julian Medrano

Theses and Dissertations - UTB/UTPA

The creation of a Post AP Chemistry Class to be taught at the high school level for grade 12 students is discussed. The class is to be taught under the supervision of the University of Texas Pan American professors and taught by an MS Chemistry teacher, in order to better transition students into upper level chemistry courses beyond Chemistry 1401 and 1402.

Chemical Education Experiences From The English Language Learner Perspective, Annette Flores

Theses and Dissertations - UTB/UTPA

The Rio Grande Valley (RGV) is a region populated by Spanish-speaking immigrants and their descendants producing a large English Language Learner (ELL) student population. ELLs have historically had low literacy rates and achievement levels when compared to their counterparts. In order to address this achievement gap, previous research efforts and curriculum interventions have focused on language acquisition as being the determining factor in ELL education, with little attention given to academic content acquisition. More current research efforts have transitioned into English language acquisition through academic content instruction; this present research study specifically focuses on ELL experiences in chemistry. Participants were …

Structural Basis For Sequence Specific Dna Binding And Protein Dimerization Of Hoxa13, Yonghong Zhang, Christine A. Larsen, H. Scott Stadler, James B. Ames

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

The homeobox gene (HOXA13) codes for a transcription factor protein that binds to AT-rich DNA sequences and controls expression of genes during embryonic morphogenesis. Here we present the NMR structure of HOXA13 homeodomain (A13DBD) bound to an 11-mer DNA duplex. A13DBD forms a dimer that binds to DNA with a dissociation constant of 7.5 nM. The A13DBD/DNA complex has a molar mass of 35 kDa consistent with two molecules of DNA bound at both ends of the A13DBD dimer. A13DBD contains an N-terminal arm (residues 324 - 329) that binds in the DNA minor groove, and a C-terminal helix (residues …

Asimafoetidnol: A New Sesquiterpenoid Coumarin From The Gum Resin Of Ferula Assa-Foetida, Debasish Bandyopadhyay, Manas Banerjee, Subrata Laskar, Bidyut Basak

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

Chemical investigation of the gum resin of Ferula assa-foetida L. resulted in the isolation of a new sesquiterpenoid coumarin, 7-(((E)-5-((1S,3S,6S)-3,6- dihydroxy-2,2,6-trimethylcyclohexyl)-3-methylpent-2-en-1-yl)oxy) -2H-chromen-2-one (asimafoetidnol), together with several other known compounds. The structure of asimafoetidnol was established on the basis of spectroscopic analyses. Geometry optimization of the compound has been carried out using a DFT/B3LYP/3-21G* method.

Bismuth Nitrate-Induced Novel Nitration Of Eugenol And Estradiol: An Exploratory Study, Luis Canales

Theses and Dissertations - UTB/UTPA

Molecules originating in nature have held an important place in chemistry and in society. Many of the important useful compounds of all time were first discovered in nature. Eugenol, a multi-functionalized biologically active constituent, is present in high quantity in natural clove. Eugenol is an important herb due to its medicinal activities; therefore, research on this molecule is necessary. Nitration of Eugenol was performed through various metal nitrates and solid surface combinations. Estrogens are contributors of the development of many secondary sex characteristics in females; they play various important roles in the nervous system. Direct nitration of estradiol has been …

Synthesis And Characterization Of 4,4-Prime-Distyrylbiphenyl And Its Applications In Organic Field Effect Transistors, Nestor A. Santos Jr.

Theses and Dissertations - UTB/UTPA

4,4’-distyrylbiphenyl (DSBP), an ambipolar small molecule with electroluminescent properties, was synthesized following two synthetic protocols. Accordingly, biphenyl was bromomethylated using a mixture of paraformaldehyde and hydrogen bromide in 20% to 60% isolated yields. Bromomethylated biphenyl was then reacted with triphenyl phosphine, or with triethyl phosphate to yield the corresponding triphenyl phosphonium bromide or triethyl phosphonate, respectively. DSBP was synthesized by reaction of the triphenyl phosphonium bromide or triethyl phosphonate with freshly distilled benzaldehyde according to the Wittig, or Horner-Wadsworth-Emmons protocols. DSBP from the Wittig reaction resulted in a mixture of cis-trans isomers, while the product from the Horner-Wadsworth-Emmons reaction yielded …

Biocompatibility Of Electrospun Polymer Nanofibers (Epns) With Nih 3t3 Cell Line And Interaction Of Quercetin With Different Flavonoids: Induction Of Phase Ii Enzymes In Vitro Cancer Cell Lines, Brenda S. Benavides

Theses and Dissertations - UTB/UTPA

Part I: In this study Electrospun nanofibers, Elasthane™ 55D, Elasthane™ 75D, Biospan®, Hydrothane™ and Lycra® were evaluated for their biocompatibility to be artificial tissue substitutes using NIH-3T3 fibroblast cells. A colorimetric based MTT dye reduction assay demonstrated that EPNs did not stop cell growth in vitro. Additionally, fluorescence confocal microscope images verified that cell adhesion occurred in the nanofibers, and cell growth on the EPNs over two weeks period was confirmed by DNA quantification.

Part II: This section of the thesis is focused on evaluation of chemopreventive properties of various phytochemicals by induction of Phase II enzymes. The interaction of …

Fabrication Of Poly(Vinylidene Fluoride) (Pvdf) Nanofibers Containing Nickel Nanoparticles As Future Energy Server Materials, Faheem A. Sheikh, Travis Cantu, Javier Macossay-Torres, Hern Kim

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

In the present study, we introduce Poly(vinylidene fluoride) (PVDF) nanofibers containing nickel (Ni) nanoparticles (NPs) as a result of an electrospinning. Typically, a colloidal solution consisting of PVDF/Ni NPs was prepared to produce nanofibers embedded with solid NPs by electrospinning process. The resultant nanostructures were studied by SEM analyses, which confirmed well oriented nanofibers and good dispersion of Ni NPs over them. The XRD results demonstrated well crystalline feature of PVDF and Ni in the obtained nanostructures. Physiochemical aspects of prepared nano-structures were characterized for TEM which confirmed nanofibers were welloriented and had good dispersion of Ni NPs. Furthermore, the …

Dow Chemical Vs. ‘Coercive Utopians’: Constructing The Contested Ground Of Science And Government Regulation In 1970s America, Amy M. Hay

History Faculty Publications

In 1979, the Dow Chemical Company published an excerpt from a speech by H. Peter Metzger that announced an emerging conflict in American ideals and public policy. He stated that a new kind of individual inhabited Washington, people from the counterculture who were “coercive utopians” because they sought to achieve their agenda through covert actions and hoped to end the American free market economy. Following the 1962 publication of Rachel Carson’s Silent Spring and the subsequent banning of DDT in 1972, Dow and other chemical manufacturers fought to keep the regulatory climate favorable to industry. Dow found itself defending the …

Microwave-Induced Bismuth Nitrate-Mediated Selective Hydrolysis Of Amide, Debasish Bandyopadhyay, Rene Solano Fonseca, Bimal K. Banik

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

Microwave-induced selective hydrolysis of amide to the corresponding amine has been achieved with bismuth nitrate and montmorillonite KSF clay.

An Easy And Straightforward Route For The Synthesis Of Disubstituted Imidazoles, Debasish Bandyopadhyay, Yvette Mora, Jesus A. Trevino-Cantu, Bimal K. Banik

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

A simple and high-yielding procedure has been developed to synthesize disubstituted imidalozes using phenyl glyoxal monohydrate, ammonium acetate and aldehydes. This synthetic protocol allows the preparation of a variety of 2,4 (s)-disubstituted imidalozes without using any catalyst, expensive or sensitive reagents. A corresponding 2-aroyl-4(s) disubstituted imidalozes derivative has also been isolated as byproduct. The effects of solvents have also been studied.

Microwave-Induced Bismuth Nitrate-Catalyzed Electrophilic Substitution Of 7-Aza Indole With Activated Carbonyl Compound Under Solvent-Free Conditions, Sonya Rivera, Debasish Bandyopadhyay, Bimal K. Banik

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

An expeditious microwave-induced synthetic method for the preparation of bis(azaindollyl)methane derivative has been developed through a bismuth nitrate-catalyzed reaction of 7-azaindole with diethylketomalonate under solvent-free conditions.

Microwave-Induced N-Bromosuccinimide-Mediated Novel Synthesis Of Pyrroles Via Paal-Knorr Reaction, Rosemarie Andoh-Baidoo, Roberto Danso, Sanghamitra Mukherjee, Debasish Bandyopadhyay, Bimal K. Banik

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

An expeditious rapid synthesis of N-substituted pyrroles using microwave-induced Nbromosuccinimide- mediated solventless reaction of 2,5-hexanedione and primary amine has been accomplished.

Microwave-Induced Bismuth Nitrate-Catalyzed Electrophilic Substitution Of Indole With Keto Ester Under Slovent-Free Conditions, Sonya Rivera, Laura Iglesias, Debasish Bandyopadhyay, Bimal K. Banik

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

Microwave-induced preparation of bis(indollyl)methane derivative has been developed through a bismuth nitrate-catalyzed reaction of indole with diethylketomalonate under solventfree conditions.

Microwave-Induced Indium-Catalyzed Synthesis Of Pyrrole Fused With Indoline In Water, Dina Abrego, Debasish Bandyopadhyay, Bimal K. Banik

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

An expeditious microwave-induced indium metal-catalyzed synthesis of pyrrole fused with indoline in water is developed by reacting isatin and 4-hydroxyproline.

Microwave-Induced Bismuth Nitrate-Catalyzed Expeditious Enamination Of Β-Dicarbonyl Compounds Under Solvent-Free Conditions, Debasish Bandyopadhyay, Bimal K. Banik

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

Bismuth nitrate-catalyzed, automated microwave-assisted expeditious synthesis of β- enaminones and β-enaminoesters has been carried out in an efficient manner under solvent-free condition. The reaction is general for primary, secondary (cyclic, heterocyclic and acyclic), benzylic as well as aromatic amines.

Antimicrobial Activity Of Eugenol Derivatives, George Eyambe, Luis Canales, Bimal K. Banik

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

The antibacterial properties of the clove plant are due to the presence of eugenol, an aromatic phenolic compound. Eugenol was isolated from clove by stem distillation. The alkene group in eugenol was epoxidized resulting in the synthesis of epoxide-eugenol. The heterocyclic ring in epoxide was cleaved to a bromoalcohol derivative. The compounds synthesized epoxideeugenol, bromo alcohol and euginol were tested for antimicrobial activity against Staphylococcus aureus (ATCC 25923). Epoxide-eugenol was found to be the most effective antimicrobial agent among the three compounds tested.

Phosphoric Acid Catalyzed Aza-Michael Reaction In Water: An Ecofriendly Procedure, Debasish Bandyopadhyay, Stephanie Maldonado, Bimal K. Banik

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

Phosphoric acid catalyzed aza-Michael reaction in water has been carried out in an efficient manner at room temperature. The reaction is general for primary, secondary (cyclic, heterocyclic and acyclic), benzylic as well as aromatic amines. No bis-addition was observed for primary amines.

Sythesis Of Glucose Peracetate Via Bismuth Nitrate-Induced Reaction, Jose Lerma, Bimal K. Banik

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

Simple synthesis peracetylated glucose has been achieved starting from glucose and acetic anhydride in the absence of solvent via bismuth nitrate-catalyzed reaction. This method does not need large excess of acetic anhydride.

Microwave-Induced Stereoselectivity Of Β-Lactam Formation: Effects Of Solvents, Debasish Bandyopadhyay, Marco Yanez, Bimal K. Banik

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

Synthesis of 3, 4-disubstituted 2-azetidinones has been achieved following Staudinger reaction under microwave-induced conditions. The stereoselectivity of β-lactam formation depends on the nature of the solvents used in the reaction.

Spectral Reflectance As An Indicator Of Foliar Concentrations Of Arsenic In Common Sunflower (Helianthus Annuus), Yuridia Patricia Peralta De Gandy

Theses and Dissertations - UTB/UTPA

Studies were conducted to investigate the use of spectral reflectance by foliage of common sunflower as a potential indicator of arsenic contamination of soil. Germination method was developed for sunflower seeds, and cohorts of sunflower seedlings in hydroponic tanks were established. The cohorts were exposed to 0 ppm, 5 ppm, 7.5 ppm, and 10 ppm treatments of As (V) and reflectance measurements of foliage were collected using a spectroradiometer during two experiments.Results demonstrated the feasibility of using spectral reflectance by foliage of common sunflower as a potential indicator of arsenic contamination. In both experiments, arsenic concentrations in leaf tissues were …

A Highly Efficient Bismuth Salts-Catalyzed Route For The Synthesis Of Alpha-Aminophosphonates, Antara Banik, Sahil Batta, Debasish Bandyopadhyay, Bimal K. Banik

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

A convenient synthesis of different types of α-amino phosphonates via one-pot solvent-free three component reactions of aldehydes, amines and phosphites catalyzed by bismuth salts has been investigated. Bismuth triflate is found to be the most effective catalyst for this reaction.

Importance Of Electronic Relaxation For Inter-Coulombic Decay In Aqueous Systems, Craig P. Schwartz, Shervin Fatehi, Richard J. Saykally, David Prendergast

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

Inspired by recent photoelectron spectroscopy experiments on hydroxide solutions, we have examined the conditions necessary for enhanced (and, in the case of solutions, detectable) inter-Coulombic decay (ICD)—Auger emission from an atomic site other than that originally excited. We present general guidelines, based on energetic and spatial overlap of molecular orbitals, for this enhancement of inter-Coulombic decay-based energy transfer in solutions. These guidelines indicate that this decay process should be exhibited by broad classes of biomolecules and suggest a design criterion for targeted radiooncology protocols. Our findings show that photoelectron spectroscopy cannot resolve the current hydroxide coordination controversy.

Study On Energy Absorption Behaviors Of Hydrophobic Mesoporous Materials, Zhongyuan Sun

Theses and Dissertations - UTB/UTPA

Nanoporous energy absorption system has been developed tremendously as an advanced energy storage system in recent years. This research is to optimize the mesoporous energy absorption matrixes via surface treatment to find out the optimum conditions for higher energy conversion efficiency. Five mesoporous silica matrixes with pore size in a range of 3 to 31.6 nm were investigated. Six alkylchlorosilanes were used as the modification reagents. The results showed that the energy absorption density via pressure-induced infiltration is as high as 8.0 J/g which is 100 times larger than that of conventional energy absorption materials. The controllability of the energy …