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Articles 931 - 960 of 1428
Full-Text Articles in Chemistry
Application Of Lipid Styryl Dye For Staining Intracytoplasmic Membranes In Gram-Negative Bacteria, Theodore J. Hammer
Application Of Lipid Styryl Dye For Staining Intracytoplasmic Membranes In Gram-Negative Bacteria, Theodore J. Hammer
Williams Honors College, Honors Research Projects
Intracytoplasmic membranes are structures that form within cells which help facilitate a variety of different metabolic processes. This feature of intracellular membranes makes them particularly valuable for studying compartmentalization and cell dynamics in bacteria. In the past, transmission electron microscopy has been the primary method for imaging bacteria with intracytoplasmic membranes. Because transmission electron microscopy takes images of a cell in fixed slices, it’s impossible to follow a cell’s growth and development over time. Fluorescence microscopy is a particularly effective method of measurement that can combat these issues when evaluating live bacterial cells. Here, standard biochemical laboratory procedures were used …
Nmr T₁ Studies Of Colloidal Unimolecular Polymer (Cup) Surface Water, Yousef Abobaker Dawib
Nmr T₁ Studies Of Colloidal Unimolecular Polymer (Cup) Surface Water, Yousef Abobaker Dawib
Doctoral Dissertations
"This dissertation is subdivided into three topics: Experimental study of colloidal unimolecular polymer (CUP) hydration; probing of polymer chain dynamics by 13C solid state NMR technique; and the anticorrosive effect of 5-mercapto-1, 3, 4-thiadiazole-2(3H)-thione (MTT) derivatives.
The states of water in colloidal unimolecular polymer system were investigated by low field proton NMR. Bound and free water fractions were determined using spin-lattice relaxation measurements. A model equation was used to analyze the inversion recovery data.
The proton cross polarization and the pulse sequence for total spinning sideband suppression CP-TOSS NMR method were developed to determine the chain mobility of polymers …
Synthesis And Electrochemical Studies Of Novel Ionic Liquid Based Electrolytes, Avinash Raju Vadapalli
Synthesis And Electrochemical Studies Of Novel Ionic Liquid Based Electrolytes, Avinash Raju Vadapalli
Doctoral Dissertations
"Room temperature ionic liquids (RTILs) have received substantial interest as nonaqueous electrolytes in lithium ion- and metal-air batteries in recent years due to their low volatility, non-flammability, wide liquid range, and thermal stability characteristics. Towards developing a new generation of high specific energy lithium ion batteries, a series of imidazolium and pyrrolidinium based ionic liquids were synthesized and explored as nonaqueous electrolytes in lithium-, lithium ion-, and lithium-air batteries. Pyrrolidinium-TFSI based ionic liquids have wide electrochemical stability (5.7 - 6.2 V vs Li/Li+); however, they show limited thermal stabilities and lithium cell discharge characteristics. TFSI-based ionic liquids are …
A Simple And Rapid Lc-Ms/Ms Method For The Determination Of Bmcl26 A Novel Anti-Parasitic Agent In Rat Plasma, Ramakrishna R. Voggu, Xiang Zhou, Bing Su, Baochuan Guo
A Simple And Rapid Lc-Ms/Ms Method For The Determination Of Bmcl26 A Novel Anti-Parasitic Agent In Rat Plasma, Ramakrishna R. Voggu, Xiang Zhou, Bing Su, Baochuan Guo
Chemistry Faculty Publications
BMCL26 is a potential drug derived from nimesulide, which has exhibited the substantial anti-parasitic activity in various cell lines. To conduct various pharmacological and toxicological properties of this drug, we developed and validated a rapid LC-MS/MS method for its quantification in accordance with the FDA guidelines. Protein precipitation with 0.1% formic acid in acetonitrile was used to extract the analytes along with the internal standard (JCC76) from rat plasma. It was found that the calibration curve of the method had an excellent linearity (r2 ≥ 0.9993) for the analyte concentration ranging from 0.5 to 100 ng/mL with acceptable inter- and …
Specific N-Glycans Of Hepatocellular Carcinoma Cell Surface And The Abnormal Increase Of Core-Α-1, 6-Fucosylated Triantennary Glycan Via N-Acetylglucosaminyltransferases-Iva Regulation, Huan Nie, Xia Liu, Yubao Zhang, Tingting Li, Chao Zhan, Wenjuan Huo, Anshun He, Yuanfei Yao, Yu Jin, Youpeng Qu, Xue-Long Sun, Yu Li
Specific N-Glycans Of Hepatocellular Carcinoma Cell Surface And The Abnormal Increase Of Core-Α-1, 6-Fucosylated Triantennary Glycan Via N-Acetylglucosaminyltransferases-Iva Regulation, Huan Nie, Xia Liu, Yubao Zhang, Tingting Li, Chao Zhan, Wenjuan Huo, Anshun He, Yuanfei Yao, Yu Jin, Youpeng Qu, Xue-Long Sun, Yu Li
Chemistry Faculty Publications
Glycosylation alterations of cell surface proteins are often observed during the progression of malignancies. The specific cell surface N-glycans were profiled in hepatocellular carcinoma (HCC) with clinical tissues (88 tumor and adjacent normal tissues) and the corresponding serum samples of HCC patients. The level of core-α-1,6-fucosylated triantennary glycan (NA3Fb) increased both on the cell surface and in the serum samples of HCC patients (p < 0.01). Additionally, the change of NA3Fb was not influenced by Hepatitis B virus (HBV)and cirrhosis. Furthermore, the mRNA and protein expression of N-acetylglucosaminyltransferase IVa (GnT-IVa), which was related to the synthesis of the NA3Fb, was substantially increased in HCC tissues. Knockdown of GnT-IVa leads to a decreased level of NA3Fb and decreased ability of invasion and migration in HCC cells. NA3Fb can be regarded as a specific cell surface N-glycan of HCC. The high expression of GnT-IVa is the cause of the abnormal increase of NA3Fb on the HCC cell surface, which regulates cell migration. This study demonstrated the specific N-glycans of the cell surface and the mechanisms of altered glycoform related with HCC. These findings lead to better understanding of the function of glycan and glycosyltransferase in the tumorigenesis, progression and metastasis of HCC.
Extremely Strong Tubular Stacking Of Aromatic Oligoamide Macrocycles, Mark A. Kline, Xiaoxi Wei, Ian J. Horner, Rui Liu, Shuang Chen, Si Chen, Ka Yi Yung, Kazuhiro Yamato, Zhonghou Cai, Frank V. Bright, Xiao Cheng Zeng, Bing Gong
Extremely Strong Tubular Stacking Of Aromatic Oligoamide Macrocycles, Mark A. Kline, Xiaoxi Wei, Ian J. Horner, Rui Liu, Shuang Chen, Si Chen, Ka Yi Yung, Kazuhiro Yamato, Zhonghou Cai, Frank V. Bright, Xiao Cheng Zeng, Bing Gong
Xiao Cheng Zeng Publications
As the third-generation rigid macrocycles evolved from progenitor 1, cyclic aromatic oligoamides 3, with a backbone of reduced constraint, exhibit extremely strong stacking with an astoundingly high affinity (estimated lower limit of Kdimer > 1013 M–1 in CHCl3), which leads to dispersed tubular stacks that undergo further assembly in solution. Computational study reveals a very large binding energy (–49.77 kcal mol–1) and indicates highly cooperative local dipole interactions that account for the observed strength and directionality for the stacking of 3. In the solid-state, X-ray diffraction (XRD) confirms that the aggregation of 3 results …
Fabrication And Study Of Graphene-Based Nanocomposites For Sensing And Energy Storage, Matthew Mcinnis
Fabrication And Study Of Graphene-Based Nanocomposites For Sensing And Energy Storage, Matthew Mcinnis
Electronic Theses and Dissertations
Graphite is an allotrope of carbon made up of atomically thin sheets, each covalently bound together, forming a π-conjugated network. An individual layer, called graphene, has extraordinary electrical, thermal and physical properties that provide the opportunity for innovating new functional composites. Graphene can be produced directly on a metallic substrate by chemical vapor deposition or by chemical oxidation of graphite, forming a stable aqueous suspension of graphene oxide (GO), which allows for convenient solution processing techniques. For the latter, after thermal or chemical reduction, much of the properties of the starting graphene re-emerge due to the reestablishment of π-conjugation. The …
Low-Level Mercury Causes Inappropriate Activation In T And B Lymphocytes In The Absence Of Antigen Stimulation, K. L. Weigand, J. L. Reno, B. M. Rowley
Low-Level Mercury Causes Inappropriate Activation In T And B Lymphocytes In The Absence Of Antigen Stimulation, K. L. Weigand, J. L. Reno, B. M. Rowley
Journal of the Arkansas Academy of Science
The immune system primarily utilizes two cell types for adaptive immunity: T lymphocytes and B lymphocytes. T lymphocytes are activated when antigen presenting cells (APCs) present antigen to membrane-bound T cell receptors. B lymphocytes are activated when an antigen binds to receptors embedded in the plasma membrane. In both T and B cells this antigen binding crosslinks the receptor complexes and initiates the signal transduction cascade. These cascades frequently consist of a series of intracellular molecules becoming phosphorylated in a step-wise fashion. Once activated, these cells differentiate into effector cells that clear out the stimulating antigen. Mercury, which is a …
Total Synthesis Of Biologically Active Natural And Unnatural Products, Julia Heimberger
Total Synthesis Of Biologically Active Natural And Unnatural Products, Julia Heimberger
College of Graduate Studies: Theses & Dissertations
Herbarin A and B were isolated from the fungal strains of Cladosporium herbarum found in marine sponges Aplysina aerophoba and Callyspongia aerizusa. Total synthesis of Herbarin A and B was achieved by carrying out a multi-step synthesis approach, and the antioxidant properties were evaluated using FRAP assay. Toxicity of these compounds was determined using a zebrafish embryo model. Furthermore, synthesis of C-6 alkyl-azaarene derivatives of nucleosides by Csp3-H bond functionalization were investigated. Effective incorporation of 2-methylazaarene moiety at the C-6 position of the protected inosine nucleoside provided a new class of compounds with anticipated enhanced biological activity.
Palladium-Catalyzed Annulation Of 9-Halophenanthrenes With Alkynes: Synthesis, Structural Analysis, And Properties Of Acephenanthrylene-Based Derivatives, En Chih Liu, Min-Kuan Chen, Jen-Yi Li, Yao-Ting Wu
Palladium-Catalyzed Annulation Of 9-Halophenanthrenes With Alkynes: Synthesis, Structural Analysis, And Properties Of Acephenanthrylene-Based Derivatives, En Chih Liu, Min-Kuan Chen, Jen-Yi Li, Yao-Ting Wu
Chemistry Faculty Research & Creative Works
The palladium-catalyzed annulation of 9-bromoand 9-chlorophenanthrenes with alkynes gave 4,5-disubstituted acephenanthrylenes in yields of 58–95% (9 examples). Asymmetric alkynes, such as 1-phenyl-1-propyne, 1-phenyl- 1-hexyne, and 1-cyclopropyl-2-phenylethyne, regioselectively form (cyclo)alkyl-substituted products, following the regular rule that governs the carbopalladation of alkynes. This synthetic protocol can also be utilized in annulations with several p-extended bromoarenes, such as 7-5] helicene, 5- 4] helicene, 9-bromoanthracene, 3-bromoperylene, and 3-bromofluoranthene, to give the corresponding annulated products in moderate to good yields (51–86 %; 6 examples). Similarly, bromocorannulene produced highly curved 1,2-disubstituted cyclopentacorannulenes. Reactions of 6,12-dibromochrysene and 4,7-4] helicene with di(4-tolyl) ethyne provided the twofold annulated products …
Palladium-Catalyzed Reaction Of Haloarenes With Diarylethynes: Synthesis, Structural Analysis, And Properties Of Methylene-Bridged Arenes, Che-Wei Lee, En Chih Liu, Yao-Ting Wu
Palladium-Catalyzed Reaction Of Haloarenes With Diarylethynes: Synthesis, Structural Analysis, And Properties Of Methylene-Bridged Arenes, Che-Wei Lee, En Chih Liu, Yao-Ting Wu
Chemistry Faculty Research & Creative Works
Fluorenes and methylene-bridged polyarenes were easily and efficiently synthesized from haloarenes (or aryl triflates) and diarylethynes by a one-pot, two-step procedure. This protocol involves the palladium-catalyzed cycloisomerization and a subsequent base-mediated retro-aldol condensation. A major advantage is that the starting materials need not have ortho functional groups to complete the annulation. The backbone of the designed products was enlarged using dihaloarenes, highly π-conjugated haloarenes, or diarylalkynes. The mechanism of the formation of benzo[a]fluorene was investigated. The bowl-shaped structure of methylene-bridged indenocorannulene was verified by X-ray crystallography. The photophysical and electrochemical properties of the products thus prepared were investigated.
Comparing Bulk Aerosol Profiles In The Mixed Layer In Coastal Los Angeles And The Inland Empire, Taia Sean Wu
Comparing Bulk Aerosol Profiles In The Mixed Layer In Coastal Los Angeles And The Inland Empire, Taia Sean Wu
Scripps Senior Theses
Characteristic westerly sea breeze carries air over the Los Angeles Basin in Southern California to the Inland Empire approximately 50 miles inland, directly impacting air quality in both of these two highly polluted regions. As particles play a critical role in air quality and human health, this study compares the bulk aerosol profiles of the Los Angeles pollution "source" and Inland Empire "receptor" regions during the 2013 and 2014 NASA Student Airborne Research Program (SARP) campaigns onboard the NASA DC-8 airborne laboratory. The source and receptor regions were characterized by a series of missed approaches at the Los Angeles International …
Computational Studies On Bimetallic Catalysis And X-Ray Absorption Spectroscopy, Sayakkarage R. G. Fernando
Computational Studies On Bimetallic Catalysis And X-Ray Absorption Spectroscopy, Sayakkarage R. G. Fernando
LSU Doctoral Dissertations
Computational studies are very important to gain an insight into reaction mechanisms and in interpreting and understanding complicated experimental observations. This report contains a discussion on computational studies performed on bimetallic catalysis and on X-ray absorption spectroscopy of insulators. The viability of a bimetallic rhodium and cobalt catalysts for industrially important hydroformylation and aldehyde-water shift catalysis (AWS) is discussed. Density functional theory (DFT) studies were used for bimetallic catalysis and time-dependent DFT studies were used for excited state dynamics. These studies were performed using Gaussian 09 package and NWChem. Hydroformylation is experimentally performed in acetone and 30% water/acetone systems and …
Platinum Complexes With Tridentate Ligands As Models For Active Monofunctional Anticancer Drugs, Chase Koby Andrepont
Platinum Complexes With Tridentate Ligands As Models For Active Monofunctional Anticancer Drugs, Chase Koby Andrepont
LSU Doctoral Dissertations
Pt(II) complexes bind preferentially at N7 of G residues of DNA, causing DNA structural distortions associated with anticancer activity. Some distortions induced by difunctional cisplatin are also found for monofunctional Pt(II) complexes with carrier ligands having bulk projecting toward the guanine base. This ligand bulk can be correlated with impeded rotation about the Pt–N7(guanine) bond. The objective of this study is to understand the influences of in-plane bulk of Pt(Ltri)G adducts (Ltri = tridentate carrier ligand, G = guanine derivative bound to a metal, but not tethered to another nucleobase). NMR spectroscopy provided conclusive evidence that Pt(Ltri)G (Ltri = di-(2-picolyl)amine …
The Electronic Structure Of Environmentally Persistent Free Radicals Formed On Metal Oxide Surfaces, Chad Allen Thibodeaux
The Electronic Structure Of Environmentally Persistent Free Radicals Formed On Metal Oxide Surfaces, Chad Allen Thibodeaux
LSU Doctoral Dissertations
We have investigated the electronic structure of environmentally persistent free radicals (EPFRs) formed on two different metal oxides: Cu(II)O and ZnO. Cu(II)O is known to be one of the most active metal oxides to form EPFRs. ZnO, however, forms the longest-lived EPFRs. First, we examined the adsorption of phenol on different crystal faces of ZnO. Ultraviolet photoelectron spectroscopy (UPS) shows direct evidence of charge transfer away from the ZnO to the phenol. This differs from the hypothesized mechanism of EPFR formation that says that an electron is transferred to the metal oxide. UPS difference spectra also shows that the phenol …
Synthetic Methods Development Towards The Total Synthesis Of Chlorosulfolipids, Andres Villalpando
Synthetic Methods Development Towards The Total Synthesis Of Chlorosulfolipids, Andres Villalpando
LSU Doctoral Dissertations
The focus of this dissertation is the development of a novel chlorination reaction utilizing a triphosgene-amine based mixture towards the total synthesis of chlorosulfolipids, a subclass of naturally occurring organohalogen natural products. This novel, mild chlorination reaction will be utilized under a global chlorination strategy to chlorinate multiple alcohol substituents in one synthetic operation. Chapter one details the history of chlorosulfolipids from the early stages of their isolation, relevant structural elucidation techniques, appropriate biosynthetic discoveries, and their biological relevance to a thorough investigation of the total syntheses completed to date. These compounds demonstrate a range of biological activities and have …
Cytotoxic Activity Of Triazole-Containing Alkyl Β-D-Glucopyranosides On A Human T-Cell Leukemia Cell Line, E. Davis Oldham, Larissa M. Nunes, Armando Varela-Ramirez, Stephen E. Rankin, Barbara L. Knutson, Renato J. Aguilera, Hans-Joachim Lehmler
Cytotoxic Activity Of Triazole-Containing Alkyl Β-D-Glucopyranosides On A Human T-Cell Leukemia Cell Line, E. Davis Oldham, Larissa M. Nunes, Armando Varela-Ramirez, Stephen E. Rankin, Barbara L. Knutson, Renato J. Aguilera, Hans-Joachim Lehmler
Chemistry and Physics
Simple glycoside surfactants represent a class of chemicals that are produced from renewable raw materials. They are considered to be environmentally safe and, therefore, are increasingly used as pharmaceuticals, detergents, and personal care products. Although they display low to moderate toxicity in cells in culture, the underlying mechanisms of surfactant-mediated cytotoxicity are poorly investigated.
Traits And Roles Of Jonas Kamlet, Pioneering Chemistry Consultant, As A Guide To Contemporary Inventors, Dean F. Martin, Autumn S. Thompson
Traits And Roles Of Jonas Kamlet, Pioneering Chemistry Consultant, As A Guide To Contemporary Inventors, Dean F. Martin, Autumn S. Thompson
Chemistry Faculty Publications
As state universities feel economic pinches of reduced support from state legislatures, and as sources of federal funding for supported research projects face additional challenges, other sources of support need to be found. Two sources under consideration are royalties and licensing fees for successful patents. A good example of a successful developer of patents was Jonas Kamlet, Ph.D. (1914‐1960), who was an early consultant in chemical and other matters and was the successful co-owner, with his wife Edna, of the Kamlet Laboratories. The roles that he played in his career can, we believe, provide good examples for contemporary researchers in …
Generation Of 2-Adamantylidenecarbene From A Phenanthrene-Based Precursor, Christine E. Wamsley
Generation Of 2-Adamantylidenecarbene From A Phenanthrene-Based Precursor, Christine E. Wamsley
Honors Theses
This thesis examines the generation of 2-adamantylidenecarbene from a phenanthrene-based precursor. A three-step synthetic procedure was used to generate the 2-adamantylidenecarbene precursor, which subsequently underwent photolysis to produce 2-adamantylidenecarbene. This product was trapped with cyclohexene. No evidence of a ring expansion to 4-homoadamantyne was observed. It was also noted that the target precursor underwent rearrangement during photolysis, leading to the formation of an isomer containing a seven-membered ring. This isomer did not photolyze. Additionally, computational studies were performed using Gaussian 09. Geometries were initially optimized and then, the single point energies of the singlet and triplet carbene states were calculated. …
Interpretation Of Complexometric Titration Data: An Intercomparison Of Methods For Estimating Models Of Trace Metal Complexation By Natural Organic Ligands, I. Pižeta, S. G. Sander, R. J. M. Hudson, D. Omanović, O. Baars, K. A. Barbeau, K. N. Buck, R. M. Bundy, G. Carrasco, P. L. Croot
Interpretation Of Complexometric Titration Data: An Intercomparison Of Methods For Estimating Models Of Trace Metal Complexation By Natural Organic Ligands, I. Pižeta, S. G. Sander, R. J. M. Hudson, D. Omanović, O. Baars, K. A. Barbeau, K. N. Buck, R. M. Bundy, G. Carrasco, P. L. Croot
OES Faculty Publications
With the common goal of more accurately and consistently quantifying ambient concentrations of free metal ions and natural organic ligands in aquatic ecosystems, researchers from 15 laboratories that routinely analyze trace metal speciation participated in an intercomparison of statistical methods used to model their most common type of experimental dataset, the complexometric titration. All were asked to apply statistical techniques that they were familiar with to model synthetic titration data that are typical of those obtained by applying state-of-the-art electrochemical methods – anodic stripping voltammetry (ASV) and competitive ligand equilibration-adsorptive cathodic stripping voltammetry (CLE-ACSV) – to the analysis of natural …
A Simpler Route To Building Photochromic Cinnamaldehyde Semicarbazones, Byron R. Ebbert
A Simpler Route To Building Photochromic Cinnamaldehyde Semicarbazones, Byron R. Ebbert
Masters Theses
Photochromic semicarbazones are an interesting group of compounds that show potential in a broad range of applications, including as a more environmentally friendly replacement for photochromic metal complex compounds. Previous work has shown the feasibility to synthesize photochromic cinnamaldehyde semicarbazones (CSCs) from a benzaldehyde and a protected acetaldehyde Wittig reagent. A new, quicker, and cheaper approach to constructing these CSCs from crotonaldehyde was explored in this research. A three reaction sequence would convert crotonaldehyde to a CSC; first, an allylic bromination of the semicarbazone with N-bromosuccinimide (NBS); second, an Arbuzov reaction to prepare the semicarbazone phosphonate; and finally a condensation …
Derivatization And Separation Of Natural Estrogens (Estrone, 17Β-Estradiol, And Estriol) Using Gas Chromatography With Flame Ionization Detection (Gc-Fid), Dena L. Guptill
Masters Theses
A major cause of concern for estrogens found in the environment is that even at very low concentrations (10-100 ng/L) they can have a negative effect on aquatic ecosystems by disrupting endocrine systems. Due to the increasing importance of monitoring the levels of estrogens in the environment, a detection method was developed to identify and quantify three natural estrogens (estrone, 17β-estradiol and estriol) using gas chromatography with flame ionization detection (GC-FID). In addition, the efficacy of two derivatizing agents, N,O-bis(trimethylsilyl) acetamide (BSTA) and N,O-bis(trimethylsilyl)trifluoroacetamide (BSTFA), was evaluated. The GC detector (FID) was most responsive with E3, followed by E1 and …
Investigation Of Β-Cyclodextrin's Ability In Differentiating Chiral Guest Molecules And Synthesis Of 1,6-Diphenyl-2,4-Hexadiene-1,6-Dione, Guang Yang
Masters Theses
This research work comprised two projects. The first one mainly focused on the synthesis of 12 alanine derivatives and analysis of their interactions with β-cyclodextrin through 1H NMR titration. And the other project was an investigation of the conjugation effect of alkynones in its addition reactions with tributyltin hydride.
The synthesis of the alanine derivatives involved methyl esterification of alanine and then the substitution of an NH hydrogen with a benzoyl group. A total of 4 different substitution groups, labeled as the "A" groups, were introduced on the para-position of the benzoyl's phenyl group. Since alanine has one chiral …
Novel Bodipy Dyes For Dye-Sensitized Solar Cells, Hafsah Klfout
Novel Bodipy Dyes For Dye-Sensitized Solar Cells, Hafsah Klfout
Masters Theses
Dyes-sensitized solar cells (DSCs) are of importance to efficient conversion of solar energy to electricity. The modern version of a DSC is a titanium dioxide nanoparticles-based electrochemical device, in which solar energy is absorbed by dye molecules and electrons from excited dye molecules are injected into the conduction band of titanium dioxide nanoparticle. The electrons are then transported through a network of interconnected TiO2 particles to the fluorine- tin -oxide layer to the external circuit. In this process dye molecules are crucial to the device's energy conversion efficiency.
Boron-dipyrromethenes, known as BODIPY dyes, show strong absorption in the visible …
A Convergent Approach To The Continuous Synthesis Of Telmisartan Via A Suzuki Reaction Between Two Functionalized Benzimidazoles, Alex D. Martin
A Convergent Approach To The Continuous Synthesis Of Telmisartan Via A Suzuki Reaction Between Two Functionalized Benzimidazoles, Alex D. Martin
Theses and Dissertations
A direct and highly efficient synthesis has been developed for telmisartan, the active ingredient in the widely prescribed antihypertensive drug Micardis®. This approach brings together two functionalized benzimidazoles using a high-yielding Suzuki reaction that can be catalyzed by a homogeneous palladium source or palladium on a solid support.
The ability to perform the cross-coupling reaction was facilitated by the regio-controlled preparation of a 2-bromo-1-methylbenzimidazole precursor. The method developed is the first reported selective bromination at the 2-position of a benzimidazole and produces the first major precursor in high yield (93%). The second precursor, potassium (4-methyl-2-propylbenzimidazol-6-yl) trifluoroborate, was prepared from commercially …
Analytical Method Development For The Detection And Analysis Of Protein Carbonyls, Chelsea M. Coffey
Analytical Method Development For The Detection And Analysis Of Protein Carbonyls, Chelsea M. Coffey
Theses and Dissertations
Oxidative stress can result in changes to many biomolecules and also affect their activities. We are interested in protein carbonylation, a type of unnatural oxidation which has been associated with numerous degenerative disease states and is also a consequence of the natural aging process. Protein carbonyls are stable species, but countless analytical barriers exist in terms of their identification. Thus, the main goal of this work was to develop and optimize analytical methods that could be used to help us better understand which, where, and how proteins are being carbonylated.
Initial studies involved method validation for carbonylating, tagging, and enriching …
Development Of Non-Traditional Platinum Anticancer Agents: Trans-Platinum Planar Amine Compounds And Polynuclear Platinum Compounds, Daniel E. Lee
Development Of Non-Traditional Platinum Anticancer Agents: Trans-Platinum Planar Amine Compounds And Polynuclear Platinum Compounds, Daniel E. Lee
Theses and Dissertations
Development of Non-Traditional Platinum Anticancer Agents: trans-Platinum Planar Amine Compounds and Polynuclear Platinum Compounds
By Daniel E. Lee, Ph.D.
A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University.
Virginia Commonwealth University, 2015
Major Director: Nicholas P Farrell, Ph.D., Professor, Department of Chemistry
Platinum anticancer compounds with cis geometry, similar to cisplatin, have been explored to circumvent the cisplatin resistance; however, they were not considered broadly active in cisplatin cells due to exhibiting similar or same cell death mechanism as cisplatin. Platinum compounds with trans geometry were less studied …
Kinetics And Performance Studies Of A Switchable Solvent Tmg (1,1,3,3-Tetramethylguanidine)/1-Propanol/Carbon Dioxide System, Özge Yüksel, Mustafa Çağdaş Öztürk, Ayça Şeker, Erdoğan Alper
Kinetics And Performance Studies Of A Switchable Solvent Tmg (1,1,3,3-Tetramethylguanidine)/1-Propanol/Carbon Dioxide System, Özge Yüksel, Mustafa Çağdaş Öztürk, Ayça Şeker, Erdoğan Alper
Turkish Journal of Chemistry
The rate constants and the activation energies of the reaction between carbon dioxide and 1,1,3,3-tetramethylguanidine (TMG) in 1-propanol solution were measured by a stopped-flow technique at a temperature range of 288--308 K and at a TMG concentration range of 2.5--10.0 wt %. Based on the pseudo-first-order reaction for CO_2, the reaction was modeled by a termolecular reaction mechanism, which resulted in a rate constant of 199.30 m^3 kmol^{-1} s^{-1} at 298 K. The activation energies were 5.19 kJ/mol and 5.26 kJ/mol at 2.5 and 5.0 wt % TMG, respectively. In addition, carbon dioxide absorption capacity was investigated using a gas--liquid …
Secondary Metabolites From Sambucus Ebulus, İrem Atay, Hasan Kirmizibekmez, Ahmet Ceyhan Gören, Erdem Yeşi̇lada
Secondary Metabolites From Sambucus Ebulus, İrem Atay, Hasan Kirmizibekmez, Ahmet Ceyhan Gören, Erdem Yeşi̇lada
Turkish Journal of Chemistry
A new nonglycosidic iridoid, sambulin B (1), was isolated from the methanol extract of Sambucus ebulus L. leaves along with a recently reported new nonglycosidic iridoid, 10-O-acetylpatrinoside aglycone (sambulin A) (2); 2 flavonoids, isorhamnetin-3-O-\beta-D-glucopyranoside (3) and isorhamnetin-3-O-rutinoside (4); and a mixture of 2 flavonoids (5), quercetin-3-O-\beta-D-glucopyranoside and quercetin-3-O-\beta-D-galactopyranoside. Their structures were elucidated by 1-D and 2-D nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS) experiments.
Synthesis And Evaluation Of Antioxidant Activities Of Novel 1,3,4-Oxadiazole And Imine Containing 1h-Benzimidazoles, Ayşe Selen Alp, Gülgün Kilcigi̇l, Elçi̇n Deni̇z Özdamar, Tülay Çoban, Bi̇nay Eke
Synthesis And Evaluation Of Antioxidant Activities Of Novel 1,3,4-Oxadiazole And Imine Containing 1h-Benzimidazoles, Ayşe Selen Alp, Gülgün Kilcigi̇l, Elçi̇n Deni̇z Özdamar, Tülay Çoban, Bi̇nay Eke
Turkish Journal of Chemistry
Some novel 2-(substitutedbenzylthio)-5-((2-(4-substitutedphenyl)-1H-benzo[d]imidazol-1-yl)methyl)-1,3,4-oxadiazoles (5--12) and 2-(2-(4-chlorophenyl)-1H-benzo[d]imidazol-1-yl)-N'-(arylmethylene)acetohydrazide derivatives (13--22) were prepared and their in vitro antioxidant properties were investigated by determination of rat liver microsomal NADPH-dependent inhibition of lipid peroxidation (LP) levels and microsomal ethoxyresorufin O-deethylase (EROD) activity. Compound 18 was found to be the most active compound with 100% inhibition on LP level and 92% inhibition on EROD. Compounds 4b, 17, and 19 showed the strongest inhibitory effect (97%) on EROD. The free radical scavenging capacities of the compounds were also tested in vitro determining the interaction of the stable free radical 2,2,diphenyl-1-picrylhydrazyl (DPPH), and compounds 4a and 4b exhibited …