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Poly(4-Vinylpyridine)-Supported Dual Acidic Ionic Liquid: An Environmentally Friendly Heterogeneous Catalyst For The One-Pot Synthesis Of 4,4'-(Arylmethylene)Bis(3-Methyl-1-Phenyl-1h-Pyrazol-5-Ols), Kaveh Parvanak Boroujeni, Pegah Shojaei Jan 2013

Poly(4-Vinylpyridine)-Supported Dual Acidic Ionic Liquid: An Environmentally Friendly Heterogeneous Catalyst For The One-Pot Synthesis Of 4,4'-(Arylmethylene)Bis(3-Methyl-1-Phenyl-1h-Pyrazol-5-Ols), Kaveh Parvanak Boroujeni, Pegah Shojaei

Turkish Journal of Chemistry

A poly(4-vinylpyridine)-supported Brønsted ionic liquid was easily prepared from its starting materials and used as a novel, highly efficient, and reusable heterogeneous catalytic system for the synthesis of 4,4'-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ols) from the condensation reaction between aromatic aldehydes and 2 equivalents of 3-methyl-l-phenyl-5-pyrazolone.


Synthesis Of 3,4-Diaryl-1-Phenyl-4,5-Dihydro-1h-Pyrazole-5-Carbonitriles Via 1,3-Dipolar Cycloaddition Reactions, Jayaroopa Prabhashankar, Vasanth Kumar Govindappa, Ajay Kumar Kariyappa Jan 2013

Synthesis Of 3,4-Diaryl-1-Phenyl-4,5-Dihydro-1h-Pyrazole-5-Carbonitriles Via 1,3-Dipolar Cycloaddition Reactions, Jayaroopa Prabhashankar, Vasanth Kumar Govindappa, Ajay Kumar Kariyappa

Turkish Journal of Chemistry

Nitrile imines generated by the oxidative dehydrogenation of aromatic aldehyde phenylhydrazones with chloramine-T as a catalytic dehydrogenating agent were trapped in situ by 4-methoxy cinnamonitrile to afford 3,4-diaryl-1-phenyl-4,5-dihydro-1H-pyrazole-5-carbonitrile in moderate to good yields. The structures of the cycloadducts were confirmed by spectral studies and elemental analysis.


Synthesis Of Tetrakis(Carboxyphenyl)Porphyrin Coated Paramagnetic Iron Oxide Nanoparticles Via Amino Acid For Photodegradation Of Methylene Blue, Rahmatollah Rahimi, Azadeh Tadjarodi, Mina Imani, Mahboubeh Rabbani, Samaneh Safalou Moghaddam, Hamed Kerdari Jan 2013

Synthesis Of Tetrakis(Carboxyphenyl)Porphyrin Coated Paramagnetic Iron Oxide Nanoparticles Via Amino Acid For Photodegradation Of Methylene Blue, Rahmatollah Rahimi, Azadeh Tadjarodi, Mina Imani, Mahboubeh Rabbani, Samaneh Safalou Moghaddam, Hamed Kerdari

Turkish Journal of Chemistry

In this paper, synthesis of tetrakis(carboxyphenyl)porphyrin (TCPP) coated cadmium ferrite (CdFe_2O_4) nanoparticles by using L-lysine as an anchor is reported for the first time. The ferrimagnetic CdFe_2O_4 nanoparticles were prepared via the facile self-assembly method of reflux followed by a heating treatment. The obtained magnetic nanoparticles were coated with TCPP in the presence of the amino acid L-lysine by sonication in ethanol and then refluxing for 12 h. The structural characteristics of the products were determined using FT-IR and XRD pattern. Scanning electron microscopy (SEM) images indicated uniform morphologies of the magnetic nanoparticles with an average size of 43 nm. …


Sesquiterpene Hydrocarbons Of The Essential Oil Of Actinolema Macrolema Boiss, Betül Demi̇rci̇, Gülden Koltuksuz Yasdikcioğlu, Kemal Hüsnü Can Başer Jan 2013

Sesquiterpene Hydrocarbons Of The Essential Oil Of Actinolema Macrolema Boiss, Betül Demi̇rci̇, Gülden Koltuksuz Yasdikcioğlu, Kemal Hüsnü Can Başer

Turkish Journal of Chemistry

The essential oils of Actinolema macrolema Boiss. (Apiaceae) were obtained by hydrodistillation in the first 3 (sample A) and the following 3 h (sample B) from crushed fruits and dried leaves (sample C), which were subsequently analyzed by GC and GC-MS. Overall, 64 components were characterized, representing 93% of the leaf oil. Thirty components were characterized from the fruit oil representing 95% of the first fraction and 90% of the second fraction consecutively. Guaia-5,7(11)-diene, selina-3,7(11)-diene, and juniper camphor were isolated from the oils by column chromatography and their structures were elucidated by GC-MS, ^1H NMR, and ^{13}C NMR. The occurrence …


Synthesis, Characterization, And Luminescence Of Zinc(Ii) And Cadmium(Ii) Coordination Complexes: [Zn(Phen)_2(Ch_3coo)](Clo_4), [Zn(Bpy)_2(Clo_4)](Clo_4), And [Cd(Phen)_2(No_3)_2], İbrahi̇m Kani̇, Mehmet Kurtça Jan 2013

Synthesis, Characterization, And Luminescence Of Zinc(Ii) And Cadmium(Ii) Coordination Complexes: [Zn(Phen)_2(Ch_3coo)](Clo_4), [Zn(Bpy)_2(Clo_4)](Clo_4), And [Cd(Phen)_2(No_3)_2], İbrahi̇m Kani̇, Mehmet Kurtça

Turkish Journal of Chemistry

Three metal complexes, [Zn(phen)_2(CH_3COO)](ClO_4) (1), [Zn(bpy)_2(ClO_4)](ClO_4) (2), and [Cd(phen)_2 (NO_3)_2] (3) (phen = 1,10-phenanthroline, bpy = 2,2 {Abedini, 2005 #222} -bipyridine), were synthesized and their structures were determined by single-crystal X-ray diffraction analyses. In 1, Zn(II) is coordinated by 4 nitrogen atoms from 2 phen molecules and 2 oxygen atoms from 1 acetato to form an octahedral configuration. In 2, Zn(II) has pentacoordination geometry with chelating 2 bpy and 1 perchlorato ion. In 3, phen and NO_3^- serve as bidentate ligands coordinating to Cd(II) through their nitrogen and oxygen atoms to form 8 coordination. Three-dimensional frameworks of complexes 1--3 are …


Simple And Convenient Preparation Of Novel 6,8-Disubstituted Quinoline Derivatives And Their Promising Anticancer Activities, Sali̇h Ökten, Osman Çakmak, Ramazan Erenler, Önem Yüce Şahi̇n, Şaban Teki̇n Jan 2013

Simple And Convenient Preparation Of Novel 6,8-Disubstituted Quinoline Derivatives And Their Promising Anticancer Activities, Sali̇h Ökten, Osman Çakmak, Ramazan Erenler, Önem Yüce Şahi̇n, Şaban Teki̇n

Turkish Journal of Chemistry

A short and easy route is described for 6,8-disubstituted derivatives of quinoline and 1,2,3,4-tetrahydroquinoli- ne from 6,8-dibromoquinolines 2 and 7 by various substitution reactions. While copper-promoted substitution of 6,8-dibromide 2 produced monomethoxides 3 and 4, a prolonged reaction time mainly afforded dimethoxide 6 instead of 5, whose aromatization with DDQ and substitution reaction of dibromide 7 with NaOMe in the presence of CuI also gave rise to dimethoxide 6. Several 6,8-disubstituted quinolines were obtained by treatment of 6,8-dibromoquinoline (7) with n-BuLi followed by trapping with an electrophile [Si(Me)_3Cl, S_2(Me)_2, and DMF]. Furthermore, 7 was also converted to mono and dicyano …


Development Of Peptide Inhibitors Targeting Clostridium Difficile Toxins A/B And Characterizing The Regulatory Role Of A Putative Negative Regulator Tcdc In Clostridium Difficile Toxin Gene Expression, Sanofar Jainul Abdeen Jan 2013

Development Of Peptide Inhibitors Targeting Clostridium Difficile Toxins A/B And Characterizing The Regulatory Role Of A Putative Negative Regulator Tcdc In Clostridium Difficile Toxin Gene Expression, Sanofar Jainul Abdeen

Wayne State University Dissertations

Clostridium difficile infections cause one of the most common and vital hospitalacquired

diseases often associated with broad-spectrum antibiotic usage. TcdA and TcdB

are the key virulence factors involved in major patho-physiology. While standard

antibiotics provide some respite, due to the high relapse rates and the emergence of more

severe disease presentations, antibiotics alone have often proven to be suboptimal.

Therefore there is a desperate need to develop an effective non-antimicrobial

therapeutics. Part of this work focuses on identification and further characterization of

peptide therapeutic that target the major virulence factor TcdA/TcdB. Towards

development of mechanistic-based anti-toxin agent, phage display was …


Synthesis Of Orthogonally Protected Azalanthionines (Lanazanines) By Sequential Ring-Opening Of N-Substituted Aziridine 2-Carboxylates, Keith O'Brien, Keith Ó Proinsias, Fintan Kelleher Jan 2013

Synthesis Of Orthogonally Protected Azalanthionines (Lanazanines) By Sequential Ring-Opening Of N-Substituted Aziridine 2-Carboxylates, Keith O'Brien, Keith Ó Proinsias, Fintan Kelleher

Articles

Orthogonally protected azalanthionines (lanazanines, 4-azadiaminopimelic acids or b-aminoalaninoalanines) have been synthesised in good yields by the ring-opening of N-protected aziridine 2-carboxylates with suitably protected diaminopropanoic acids (DAPs). The required DAPs were also synthesised by ring-opening of N-protected aziridine 2-carboxylates with para-methoxybenzylamine.


Specific Salt Effects On The Formation And Thermal Transitions Among Β-Lactoglobulin And Pectin Electrostatic Complexes, Stacey Ann Hirt Jan 2013

Specific Salt Effects On The Formation And Thermal Transitions Among Β-Lactoglobulin And Pectin Electrostatic Complexes, Stacey Ann Hirt

Open Access Theses

Factors of ion specificity and ionic strength (I~0-100) were studied in the electrostatic complex formation and protein particle formation by thermal treatment for a β-lactoglobulin and pectin system. ζ-potential showed β-lactoglobulin and pectin began to interact near pH 5.50 and interactions were strengthened with decrease in pH. Visible light turbidimetry and light scattering at 90° revealed a trend in critical pH transitions for electrostatic complex formation based on both the ionic strength and the anion of the salt species, while effects of the monovalent cation was insignificant. Critical pH values for complex formation and separation (pHc and pHΦ) decreased with …


The Design And Synthesis Of Peptidomimetic Serine-Based Prodrugs As 14-3-3 Inhibitors, Eric Drake Jones Jan 2013

The Design And Synthesis Of Peptidomimetic Serine-Based Prodrugs As 14-3-3 Inhibitors, Eric Drake Jones

Open Access Theses

Jones, Eric D. Masters of Science, Purdue University, October 2013. THE DESIGN AND SYNTHESIS OF PEPTIDOMEMETIC SERINE-BASED PRODRUGS AS 14-3-3 INHIBITORS. Major Professor: Richard Borch

This work describes the design and synthesis of peptidomimetics for the inhibition of the protein-protein interactions (PPI) with 14-3-3. This protein is a promiscuous binder of other proteins with a variety of key functions such as the regulation of proapoptotic proteins (e.g. FOXO, BAD), suppression of tumor growth, and sensitizing cells to other drugs. The promiscuous binding is the result of PPIs being shallow binding sites which accept many proteins and modify their activity. Compounds …


Fate Of 17Α-Estradiol, 17Β-Estradiol, And Estrone In Agricultural Soils And Sediments, Michael L. Mashtare Jr Jan 2013

Fate Of 17Α-Estradiol, 17Β-Estradiol, And Estrone In Agricultural Soils And Sediments, Michael L. Mashtare Jr

Open Access Dissertations

The shift to concentrated animal production facilities and increasing rural-urban migration has increased the localized land application of nearly 1 billion tons of manure and biosolids annually. Although these applications provide nutrients and contribute to soil tilth, they also serve as a source for an estimated 49 tons of the natural manure-borne estrogens, 17α-estradiol (17α-E2), 17β-estradiol (17β-E2), and estrone (E1). While these estrogens are critical to endocrine systems, the low concentrations observed in the environment can disrupt endocrine function in non-target organisms, e.g., altering secondary sex characteristics which can lead to changes in wildlife communities.

Research presented here focuses on …


Decoration Of Graphene With Metal Nanoparticles And Its Application For Bioanalysis, Keun Soo Kwon Jan 2013

Decoration Of Graphene With Metal Nanoparticles And Its Application For Bioanalysis, Keun Soo Kwon

Theses, Dissertations and Culminating Projects

Graphene is a two-dimensional monolayer of tightly packed sp2 hybridized Carbon atoms. Formed from graphite, the theoretical surface area of the monolayer is about 2630 m2/g, and the initial formation of graphene oxide from graphite oxide introduces a variety o f functional groups, such as -COOH, -C=0, and -OH, on its surface. The high surface area and the rich presence of functional groups, along with the potential formation o f sp2 bonding networks within graphene oxide, all serve as critical factors allowing for additional chemical modifications. There are extensive research attempts being performed to explore and …


From Whole-Cell To Compartment- And Class-Specific Analysis Of Rna Post-Transcriptional Modifications, Ryan Quinn Jan 2013

From Whole-Cell To Compartment- And Class-Specific Analysis Of Rna Post-Transcriptional Modifications, Ryan Quinn

Legacy Theses & Dissertations (2009 - 2024)

The genomic structure of the human immunodeficiency virus type 1 (HIV-1) has proven difficult to examine by traditional high-resolution techniques. Structural probing and in silico modeling have been turned to the task instead. Computer models are only as robust as the data used to create them. A number of techniques were explored in this investigation to expand the utility of in silico modeling as it relates to HIV-1: the study of nucleoside modifications, and the probing of in vivo conformations of the 5'-untranslated region (5'-UTR) by cross-linking and affinity capture.


Molecular Biochemical Study Of The Cataract-Associated Mutants In Human Gammad-Crystallin, Cindy Yeung Jan 2013

Molecular Biochemical Study Of The Cataract-Associated Mutants In Human Gammad-Crystallin, Cindy Yeung

Legacy Theses & Dissertations (2009 - 2024)

Cataract is a vision impairment disease that leads to light scattering and opacity of the eye lens. It is recognized as the most prevalent cause of blindness. Most cataracts occur due to aging, but those that occur in childhood or in young adults are typically of genetic origin. In the young (developing) eye, post–surgical complications such as glaucoma are common after cataract surgery. Hence there is a great need to develop non-surgical intervention strategies for the treatment of cataract. Here, two cataract-associated mutants of human γD-crystallin (HGD): i) Arg76 to Ser (R76S) and ii) a truncation mutation at Trp156 (W156X …


Structure-Activity Relationship Of 2,3-Benzodiazepin-4-Ones As Noncompetitive Ampa Receptor Antagonists, Mohammad Shaban Qneibi Jan 2013

Structure-Activity Relationship Of 2,3-Benzodiazepin-4-Ones As Noncompetitive Ampa Receptor Antagonists, Mohammad Shaban Qneibi

Legacy Theses & Dissertations (2009 - 2024)

2,3-Benzodiazepin-4-one (BDZ-11) derivatives are a special group of 2,3-benzodiazepine compounds. These compounds have been previously synthesized as AMPA receptor inhibitors, and they are also potential drugs for the treatment of various neurological diseases involving excessive AMPA receptor activity. AMPA receptors are a subtype of glutamate ion channel proteins and are responsible for the majority of excitatory neurotransmission in the mammalian central nervous system. Specifically, they are critically involved in neuronal development and brain activities, including learning and memory. Overstimulation of AMPA receptors is associated with some neurological diseases such as ALS, stroke and Alzheimer's disease. Despite the fact that hundreds …


Raman Spectroscopy For The Identification Of Body Fluid Traces : Mixtures And Contaminations, Race And Gender Differentation, Aliaksandra Sikirzhytskaya Jan 2013

Raman Spectroscopy For The Identification Of Body Fluid Traces : Mixtures And Contaminations, Race And Gender Differentation, Aliaksandra Sikirzhytskaya

Legacy Theses & Dissertations (2009 - 2024)

Body fluid traces are an important type of forensic evidence, which play a significant role in the reconstruction of a violent crime and often help to identify a victim or suspect based on DNA analysis. Despite a great need, there is no a single method, which could identify multiple body fluids. In addition, majority of current methods are destructive for the evidence. For about eight years, our laboratory has been working on the development of a new nondestructive method for identification of body fluid traces based on Raman microspectroscopy combined with advanced statistics. High differentiation power of the method has …


Vibrational Spectroscopic Analysis Of Gunshot Residue : A Novel Approach For Detection And Characterization, Justin J. Bueno Jan 2013

Vibrational Spectroscopic Analysis Of Gunshot Residue : A Novel Approach For Detection And Characterization, Justin J. Bueno

Legacy Theses & Dissertations (2009 - 2024)

Due to the increasing prevalence of firearm related crimes, there is a need for an all-encompassing analytical technique which can rapidly detect and analyze trace crime scene firearm evidence. There are several forms of ballistics and trace evidence associated with firearm offenses. Historically, the most neglected piece of evidence has ironically been the most prevalent. Each firearm discharge produces a so called gunshot residue (GSR) sample, expelling dust and particles numbering from hundreds to thousands throughout the shooting environment. The detection of GSR at a crime scene or on a suspect is critical for determining what actually happened during a …


Synthetic Approaches To Thiacorannulene, Rama Yaghi Jan 2013

Synthetic Approaches To Thiacorannulene, Rama Yaghi

Legacy Theses & Dissertations (2009 - 2024)

Thiacorannulene is an unknown, open geodesic heteropolyarene comprised of a central five-membered ring surrounded by four benzene rings and one thiophene ring. This heterobuckybowl is expected to have unique physical, chemical and biological properties. The curvature in thiacorannulene should provide two distinct surfaces, convex and concave, and should affect properties such as dipole moment, ionization potential, metal binding, etc. Having a thiophene ring embedded in its structure is expected to influence the reactivity of this compound. We sought to devise syntheses of the unknown heterobuckybowl based on earlier, optimized syntheses of buckybowls, heterobuckybowls, and heterocirculenes. Details of our attempted syntheses …


(S)-Trifluoroselenomethionine : A New Non-Natural Amino Acid With Enhanced Methioninase-Induced Cytotoxicity Toward Human Colon Cancer Cells, Stephene Nathele Lodge Jan 2013

(S)-Trifluoroselenomethionine : A New Non-Natural Amino Acid With Enhanced Methioninase-Induced Cytotoxicity Toward Human Colon Cancer Cells, Stephene Nathele Lodge

Legacy Theses & Dissertations (2009 - 2024)

Abstract


Assessment Of Human Exposure To Perchlorate And Perfluoroalkyl Substances In The United States : Biomonitoring And Environmental Monitoring Approaches, Qian Wu Jan 2013

Assessment Of Human Exposure To Perchlorate And Perfluoroalkyl Substances In The United States : Biomonitoring And Environmental Monitoring Approaches, Qian Wu

Legacy Theses & Dissertations (2009 - 2024)

Perchlorate is an oxidant in solid fuels and explosives and is produced in large quantities worldwide. Perchlorate is a ubiquitous environmental contaminant and is present in water, food, indoor environment and humans. Human exposure to perchlorate is a concern due to its ability to disrupt the thyroid gland functions.


Raman Spectroscopic Analysis Of Body Fluids : Species Differentiation And The Effect Of Substrate Interference And Laser Power, Gregory Keith Mclaughlin Jan 2013

Raman Spectroscopic Analysis Of Body Fluids : Species Differentiation And The Effect Of Substrate Interference And Laser Power, Gregory Keith Mclaughlin

Legacy Theses & Dissertations (2009 - 2024)

Several recent discoveries demonstrate that Raman spectroscopy has a unique capability to characterize body fluid traces in a forensic capacity. This approach has thus garnered interest in the forensic community since 2008, when a proof of concept experiment established that blood, semen, vaginal fluid, sweat and saliva are easily differentiable through their Raman spectra. Several possible methods of identification have been described in the literature, one approach uses chemometrical models, and another applies recently formulated multidimensional Raman signatures. The analytical sampling method and the identification procedure provide several desirable traits for the field of forensic science. In particular, Raman spectroscopy …


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 …


Controlled Transformation Of Nanoparticles With Tunable Surface Plasmon Resonance, Nimer Murshid Jan 2013

Controlled Transformation Of Nanoparticles With Tunable Surface Plasmon Resonance, Nimer Murshid

Theses and Dissertations (Comprehensive)

This thesis reports key findings in the synthesis and transformation of silver nanoparticles (AgNPs) with pentagonal symmetries. The main focus of the thesis work is on the synthesis of silver decahedral nanoparticles (AgDeNPs) and their transformation into larger AgDeNPs and silver pentagonal rod nanoparticles (AgPRNPs). In another direction, produced AgNPs were stabilized by gold plating. In a one-stage photochemical synthesis of AgDeNPs (pentagonal bipyramid, J13 solid), oxidative etching by hydrogen peroxide was implemented to achieve complete conversion of the small silver platelet precursor NPs. For convenient laboratory synthesis of high-purity size-selected AgDeNPs, we have also adapted LEDs as a …


Dinosolve: A Protein Disulfide Bonding Prediction Server Using Context-Based Features To Enhance Prediction Accuracy, Ashraf Yaseen, Yaohang Li Jan 2013

Dinosolve: A Protein Disulfide Bonding Prediction Server Using Context-Based Features To Enhance Prediction Accuracy, Ashraf Yaseen, Yaohang Li

Computer Science Faculty Publications

Background: Disulfide bonds play an important role in protein folding and structure stability. Accurately predicting disulfide bonds from protein sequences is important for modeling the structural and functional characteristics of many proteins.

Methods: In this work, we introduce an approach of enhancing disulfide bonding prediction accuracy by taking advantage of context-based features. We firstly derive the first-order and second-order mean-force potentials according to the amino acid environment around the cysteine residues from large number of cysteine samples. The mean-force potentials are integrated as context-based scores to estimate the favorability of a cysteine residue in disulfide bonding state as well as …


Fabrication Of Layer-By-Layer Deposited Films Containing Carbon Nanotubes And Poly(Malachite Green) As A Sensor For Simultaneous Determination Of Ascorbic Acid, Epinephrine, And Uric Acid, Jahan Bakhsh Raoof, Reza Ojani, Mehdi Baghayeri Jan 2013

Fabrication Of Layer-By-Layer Deposited Films Containing Carbon Nanotubes And Poly(Malachite Green) As A Sensor For Simultaneous Determination Of Ascorbic Acid, Epinephrine, And Uric Acid, Jahan Bakhsh Raoof, Reza Ojani, Mehdi Baghayeri

Turkish Journal of Chemistry

A simple approach to constructing a double-layer voltammetric sensor is described. The poly(malachite green) (PMG) and multiwalled carbon nanotubes (MWCNTs) were coimmobilized at the surface of the glassy carbon electrode (GCE) for fabrication of PMG/MWCNT/GCE. The modified electrode was characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), differential pulse voltammetry (DPV), and chronoamperometric techniques. Using DPV, the obtained catalytic peak current was linearly dependent on the ascorbic acid (AA), epinephrine (EP), and uric acid (UA) concentrations in the ranges of 0.4-100.0, 0.1-100.0, and 0.3-90.0 \muM, respectively. The resultant detection limits for AA, EP, and UA were 0.23, 0.0820, and …


New Secondary Metabolites From Croton Sparsiflorus Morong, Rashad Mehmood, Amna Bibi, Abdul Malik Jan 2013

New Secondary Metabolites From Croton Sparsiflorus Morong, Rashad Mehmood, Amna Bibi, Abdul Malik

Turkish Journal of Chemistry

Sparsifloamide (1), a new sphingolipid, and sparsifloside (2), a new diglyceride galactoside, have been isolated from the ethyl acetate soluble fraction of the 80% ethanolic extract of the whole plant of Croton sparsiflorus Morong. Their structures were assigned by ^1H- and ^{13}C-NMR spectra and DEPT, COSY, NOESY, HMQC, HMBC, and ESI-MS experiments.


Molecular Docking And Qsar Study On Imidazole Derivatives As 14 /Alpha -Demethylase Inhibitors, Asghar Davood, Maryam Iman Jan 2013

Molecular Docking And Qsar Study On Imidazole Derivatives As 14 /Alpha -Demethylase Inhibitors, Asghar Davood, Maryam Iman

Turkish Journal of Chemistry

14\alpha-Demethylase (CYP51) inhibitors have been widely used in the treatment of fungal infections. In this study, a series of imidazole derivatives with CYP51 inhibitory activity were subjected to a molecular docking study followed by quantitative structure-activity relationship (QSAR) analyses in search of the ideal physicochemical characteristics of potential CYP51 inhibitors. Desired imidazoles were built using the HyperChem program, and conformational studies were performed through a semiempirical method followed by the PM3 method. Docking study was performed using the AutoDock program on all of the compounds. Different QSAR descriptors were calculated using DRAGON, AutoDock, and HyperChem. Multilinear regression was used as …


Enaminonitriles In Heterocyclic Synthesis: Synthesis And Biological Evaluation Of Novel Indeno[2,1-B]Thiophene Derivatives, Ahmed A. Fadda, Abd El Galil M. Khalil, Eman H. Tawfik Jan 2013

Enaminonitriles In Heterocyclic Synthesis: Synthesis And Biological Evaluation Of Novel Indeno[2,1-B]Thiophene Derivatives, Ahmed A. Fadda, Abd El Galil M. Khalil, Eman H. Tawfik

Turkish Journal of Chemistry

No abstract provided.


Synthesis And Evaluation Of Acetylcholineesterase Inhibitory Potential And Antioxidant Activity Of Benzothiazine Derivatives, Durre Shahwar, Uzma Sana, Naeem Ahmad Jan 2013

Synthesis And Evaluation Of Acetylcholineesterase Inhibitory Potential And Antioxidant Activity Of Benzothiazine Derivatives, Durre Shahwar, Uzma Sana, Naeem Ahmad

Turkish Journal of Chemistry

The aim of the present study was to synthesize and characterize benzothiazine derivatives prepared by using 2-aminothiophenol and saccharine and in vitro screen their enzyme inhibition and antioxidant potential. Nine different derivatives were prepared and their structures were confirmed by spectral studies (EIMS, ^1 H and ^{13}C NMR). Enzyme inhibition potential of the synthesized compounds was evaluated by Ellman's method, while antioxidant activity was determined by DPPH and FRAP assays. All the derivatives showed remarkable activity against acetylcholine esterase with IC_{50} values in the range of 35.9--122.0 \mu M. All other derivatives, except compound 4a, were inactive towards DPPH radical. …


C_2-Symmetric Chiral Diamine Ligands For Enantiomeric Recognition Of Amino Acid Esters And Mandelic Acid By Proton Nmr Titration Method, Hayri̇ye Aral, Tarik Aral, Mehmet Çolak, Berri̇n Zi̇yadanoğullari, Recep Zi̇yadanoğullari Jan 2013

C_2-Symmetric Chiral Diamine Ligands For Enantiomeric Recognition Of Amino Acid Esters And Mandelic Acid By Proton Nmr Titration Method, Hayri̇ye Aral, Tarik Aral, Mehmet Çolak, Berri̇n Zi̇yadanoğullari, Recep Zi̇yadanoğullari

Turkish Journal of Chemistry

Two novel C_2-symmetric chiral diamines containing \alpha -phenylethyl and \alpha -(1-naphthyl)ethyl chiral subunits were prepared with quantitative yields. Enantiomeric recognition properties of these simple structured diamine ligands towards D- and L-amino acid esters and D- and L-mandelic acid were examined by the ^1H NMR titration method. These ligands exhibited strong complexation (with K_f up to 2481 M^{-1}) and good enantioselectivity (up to K_L/K_D = 4.08) towards the mandelic acid enantiomers. The results show that simple structured and easily accessible acyclic C_2-symmetrical compounds can also be used for enantiomeric recognition of racemic amino acids and mandelic acid in addition to complex …