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2014

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Articles 1021 - 1050 of 1401

Full-Text Articles in Chemistry

Aryl Butenoic Acid Derivatives As A New Class Of Histone Deacetylase Inhibitors: Synthesis, In Vitro Evaluation, And Molecular Docking Studies, Peruze Ayhan Eşi̇yok, Özlem Seven, Gülüzar Eymur, Gamze Bora Tatar, Di̇dem Dayangaç Erden, Kemal Yelekçi̇, Hayat Yurter, Ayhan Sitki Demi̇r Jan 2014

Aryl Butenoic Acid Derivatives As A New Class Of Histone Deacetylase Inhibitors: Synthesis, In Vitro Evaluation, And Molecular Docking Studies, Peruze Ayhan Eşi̇yok, Özlem Seven, Gülüzar Eymur, Gamze Bora Tatar, Di̇dem Dayangaç Erden, Kemal Yelekçi̇, Hayat Yurter, Ayhan Sitki Demi̇r

Turkish Journal of Chemistry

New aryl butenoic acid derivatives have been synthesized by combining hydroxy- or methoxy-substituted phenyl rings as the capping group, with a double bond in the short linker as well as metal binding groups, enoic ester, and salts bearing either methyl or morpholine. These compounds have been shown to possess promising histone deacetylase inhibition activities via in vitro fluorometric assay and molecular docking studies.


Application Of Guanidine And Its Salts In Multicomponent Reactions, Mahshid Rahimifard, Ghodsi Mohammadi Ziarani, Boshra Malekzadeh Lashkariani Jan 2014

Application Of Guanidine And Its Salts In Multicomponent Reactions, Mahshid Rahimifard, Ghodsi Mohammadi Ziarani, Boshra Malekzadeh Lashkariani

Turkish Journal of Chemistry

This review gives an overview of the application of guanidine and its salts in multicomponent reactions. It can act as a catalyst or solvent for multicomponent reactions or as a reagent for synthesis of substituted diazines, triazines, and macroheterocycles by multicomponent reactions.


Preparation And Characterization Of Nonmetal Promoter Modified Cuznal Catalysts For Higher Alcohol From Synthesis Gas Through Complete Liquid Phase Method, Shirui Yu, Xiaodong Wang, Wei Huang Jan 2014

Preparation And Characterization Of Nonmetal Promoter Modified Cuznal Catalysts For Higher Alcohol From Synthesis Gas Through Complete Liquid Phase Method, Shirui Yu, Xiaodong Wang, Wei Huang

Turkish Journal of Chemistry

A complete liquid phase technology and a function regulator were applied to prepare CuZnAl catalysts for higher alcohol synthesis. Characterizations showed that the introduction of the function regulator can change the reduction ability of copper oxides and the surface basicity of catalysts. Activity tests indicated that the selectivity of higher alcohol is high when considerable medium-strong basicity and the synergistic effects of copper ion and metal copper exist on the catalytic surface. The optimized modified CuZnAl catalyst without any metal additives provides a CO conversion of 28.9%, C_{2+}OH selectivity of up to 42.8%, and hydrocarbon selectivity of 2.5%, with a …


The Chemistry Concerned With The Sonochemical-Assisted Synthesis Of Ceo_2/Poly(Amic Acid) Nanocomposites, Shiva Yazdani, Mehdi Hatami, Seyed Mohammad Vahdat Jan 2014

The Chemistry Concerned With The Sonochemical-Assisted Synthesis Of Ceo_2/Poly(Amic Acid) Nanocomposites, Shiva Yazdani, Mehdi Hatami, Seyed Mohammad Vahdat

Turkish Journal of Chemistry

A series of new poly(amic acid) (PAA) surface-modified cerium oxide (CeO_2) nanocomposites were prepared by sonochemical-assisted method. In the first step, treatment of the surface of CeO_2 nanoparticles with hexadecyltrimethoxysilane as a surface modifier was achieved. In the second step, the partially surface-treated nanoparticles were incorporated into PAA by different weight from 4% to 12%. PAA was synthesized by polycondensation reaction of benzophenone tetracarboxylic dianhydride and 3,5-diamino-N-(4-hydroxyphenyl) benzamide in N-methyl-2-pyrrolidone. The chemical structure of PAA was confirmed by ^1H NMR and FTIR spectroscopy. The polymer had an inherent viscosity of 0.38 dL/g. Three PAA/CeO_2 nanocomposite formulations were prepared from the …


Crystal Growth Morphology Of Magnesium Hydroxide, Jiansong Wu, Juan Du, Yi-Min Gao Jan 2014

Crystal Growth Morphology Of Magnesium Hydroxide, Jiansong Wu, Juan Du, Yi-Min Gao

Turkish Journal of Chemistry

In this paper, the formation process of magnesium hydroxide unit cells, as well as the structural characteristics and growth morphology of magnesium hydroxide, is discussed from the perspective of growth units. The growth process of the hexagonal structure of the magnesium hydroxide is as follows: the growth units are first incorporated into a larger hexagonal dimension unit on the same plane, and then the hexagonal layers connect to each other in the z-axis direction for the hexagonal magnesium hydroxide unit cell. The results of the study show that the model of anion coordination polyhedron growth units may be reasonably deduced …


Deposition And Characterization Of Cu_9s_5 Nanocrystals From Unsymmetrical [(Hex)(Me)Nc(S)Nc(O)C_6h_3(No_2)_2-3,5]_2cu(Ii) And [(Et)(Bu)Nc(S)Nc(O)C_6h_4-4-No_2]_2cu(Ii) Complexes By Colloidal Thermolysis Method, Sohail Saeed, Rizwan Hussain Jan 2014

Deposition And Characterization Of Cu_9s_5 Nanocrystals From Unsymmetrical [(Hex)(Me)Nc(S)Nc(O)C_6h_3(No_2)_2-3,5]_2cu(Ii) And [(Et)(Bu)Nc(S)Nc(O)C_6h_4-4-No_2]_2cu(Ii) Complexes By Colloidal Thermolysis Method, Sohail Saeed, Rizwan Hussain

Turkish Journal of Chemistry

Cu_9S_5 nanocrystals were synthesized from unsymmetrical [(Hex)(Me)NC(S)NC(O)C_6H_3(NO_2)_2-3,5]_2Cu(II) and [(Et)(Bu)NC(S)NC(O)C_6H_4-4-NO_2]_2 Cu(II) complexes by colloidal thermolysis in the presence of surfactant oleylamine. The unsymmetrical copper complexes were synthesized by the reaction of copper(II) acetate with N-[hexyl(methyl)carbamothioyl]-3,5-dinitrobenzamide and N-[ethyl(butyl)carbamothioyl]-4-nitrobenzamide. The complexes were used as single-source precursors for the preparation of Cu_9S_5 nanocrsytals. The Cu_9S_5 nanocrystals were characterized by X-ray powder diffraction and transmission electron microscopy.


Investigation Of The Adsorption Kinetics Of Methylene Blue Onto Cotton Wastes, Bi̇lal Acemi̇oğlu, Murat Ertaş, Mehmet Hakki Alma, Mustafa Usta Jan 2014

Investigation Of The Adsorption Kinetics Of Methylene Blue Onto Cotton Wastes, Bi̇lal Acemi̇oğlu, Murat Ertaş, Mehmet Hakki Alma, Mustafa Usta

Turkish Journal of Chemistry

Cotton stalk (CS), cotton waste (CW), and cotton dust (CD), which are cotton wastes, were used as adsorbents to study the adsorption kinetics of methylene blue from aqueous solution. Kinetics of the batch adsorption experiment was investigated according to the pseudo-first order, the pseudo-second order, and the intraparticle diffusion models used commonly in the literature. The effects of the initial concentration, solution pH, and temperature on kinetic parameters (adsorption rate constant, initial adsorption rate, equilibrium adsorption capacity, etc.) were studied. The results showed that the adsorption process was well fitted to the pseudo-second order model for all adsorbents. The activation …


Spectroscopic Investigation And Oxidation Of The Anticholinergic Drug Atropine Sulfate Monohydrate By Hexacyanoferrate(Iii) In Aqueous Alkaline Media: A Mechanistic Approach, Manjunath Meti, Sharanappa Nandibewoor, Shivamurti Chimatadar Jan 2014

Spectroscopic Investigation And Oxidation Of The Anticholinergic Drug Atropine Sulfate Monohydrate By Hexacyanoferrate(Iii) In Aqueous Alkaline Media: A Mechanistic Approach, Manjunath Meti, Sharanappa Nandibewoor, Shivamurti Chimatadar

Turkish Journal of Chemistry

The oxidation of the anticholinergic drug atropine sulfate monohydrate by hexacyanoferrate(III) in aqueous alkaline media was investigated spectrophotometrically by monitoring the decrease in absorbance of hexacyanoferrate(III) (HCF(III)). Oxidation products were identified. The oxidation mechanism was proposed from kinetic studies. The reaction constants involved in the different steps of the mechanism were calculated. The effects of added products, ionic strength, and dielectric constant of the reaction were investigated. The polymerization test revealed that oxidation occurred with intervention of free radicals. The activation parameters were evaluated.


Selective Oxidation Of Sulfides And Hydrocarbons With H_2o_2 Over Manganese Catalyst Supported On Nanoparticles, Massomeh Ghorbanloo, Roghayeh Tarasi, Jun Tao, Hidenori Yahiro Jan 2014

Selective Oxidation Of Sulfides And Hydrocarbons With H_2o_2 Over Manganese Catalyst Supported On Nanoparticles, Massomeh Ghorbanloo, Roghayeh Tarasi, Jun Tao, Hidenori Yahiro

Turkish Journal of Chemistry

A new magnetically separable catalyst consisting of binuclear Mn(II) complex [Mn_2(HL)_2(H_2O)_4], HL = 2-[(2-hydroxy-benzylidene)-amino]-3-(4-hydroxyphenyl)-propionic acid, supported on (3-chloropropyl)-trimethoxysilane (CPTMS) functionalized silica-coated magnetic nanoparticles (MNPs) was prepared. The synthesized catalyst was characterized by several physico-chemical and spectroscopic methods. This immobilized complex was found to be an efficient heterogeneous catalyst for the oxidation of different sulfides and hydrocarbons using hydrogen peroxide (H_2O_2) as an oxidant. The catalyst is readily recovered by simple magnetic decantation and can be recycled several times with no considerable loss of catalytic activity.


Solvent Extraction Of Praseodymium(Iii) From Acidic Nitrate Medium Using Cyanex 921 And Cyanex 923 As Extractants In Kerosene, Nandita Panda, Nihar Bala Devi, Sujata Mishra Jan 2014

Solvent Extraction Of Praseodymium(Iii) From Acidic Nitrate Medium Using Cyanex 921 And Cyanex 923 As Extractants In Kerosene, Nandita Panda, Nihar Bala Devi, Sujata Mishra

Turkish Journal of Chemistry

Solvent extraction of praseodymium(III) from acidic nitrate medium by the neutral organophosphorous extractants Cyanex 921 and Cyanex 923 in kerosene was studied. The effects of various parameters like equilibration time, nitric acid concentration, nitrate ion concentration, extractant concentration, temperature, and nature of diluents on the extraction behavior of Pr(III) were investigated. The extraction of 0.001 M Pr(III) was quantitative (93%) from the aqueous phase containing 0.001 M HNO_3 and 0.1 M KNO_3 using 0.5 M Cyanex 921/1 M Cyanex 923. On the basis of slope analysis, the compositions of the extracted species were formulated as Pr(NO_3)_3.2Cyanex 921 and Pr (NO_3)_3.Cyanex …


Adsorption Of The Urea Molecule On The B_{12}N_{12} Nanocage, Mohammad Taghi Baei Jan 2014

Adsorption Of The Urea Molecule On The B_{12}N_{12} Nanocage, Mohammad Taghi Baei

Turkish Journal of Chemistry

The adsorption of the urea molecule on the external surface of the B_{12}N_{12} nanocage was investigated using density functional theory (DFT) calculations. Adsorption of urea on the nanocage releases energies of about --23.70 to --29.50 kcal/mol with a significant NBO charge transfer from the urea to the nanocage. It was also found that the urea molecule can be strongly chemisorbed on the surface of the nanocage with Gibbs free energies of -7.91 to -14.81 kcal/mol. The HOMO--LUMO gap of the nanocage does not change significantly upon urea adsorption, while the Fermi level is dramatically changed from -4.27 eV in the …


Partial Purification And Biochemical Characterization Of An Extremely Thermo- And Ph-Stable Esterase With Great Substrate Affinity, Esra Özbek, Yakup Kolcuoğlu, Leyla Konak, Ahmet Çolak, Fulya Öz Jan 2014

Partial Purification And Biochemical Characterization Of An Extremely Thermo- And Ph-Stable Esterase With Great Substrate Affinity, Esra Özbek, Yakup Kolcuoğlu, Leyla Konak, Ahmet Çolak, Fulya Öz

Turkish Journal of Chemistry

An esterase from a thermophilic bacterium, Geobacillus sp. DF20, was partially purified. Final purification factor was found to be 64.5-fold using Q-Sepharose ion exchange column chromatography. Native polyacrylamide gel electrophoresis indicated the presence of a single active esterase. The substrate specificity of this esterase was high for p-nitrophenyl butyrate (pNPB) substrate. The optimum pH and temperature for the enzyme activity were 7.0 and 50 ^°C, respectively. The pH and heat stability profiles show that this enzyme is more stable under neutral conditions at 50 ^°C. K_m and V_{max} values for this esterase acting on pNPB were 0.12 mM and 54.6 …


Application Of 3-Aroyl-4(5)-Arylimidazols As Efficient Ligands In Pd-Catalyzed Heck Reactions, Mojtaba Amini, Seyedeh Motahhareh Amini, Bagher Eftekhari-Sis, Ali Keivanloo Jan 2014

Application Of 3-Aroyl-4(5)-Arylimidazols As Efficient Ligands In Pd-Catalyzed Heck Reactions, Mojtaba Amini, Seyedeh Motahhareh Amini, Bagher Eftekhari-Sis, Ali Keivanloo

Turkish Journal of Chemistry

The Heck coupling of haloarenes with various alkenes was successfully performed in the presence of 0.25 mol % PdCl_2 and 0.5 mol % biphenyl-4-yl-[4(5)-(biphenyl-4-yl)-1H-imidazol-2-yl]ketone 2f as a ligand with Na_2CO_3 as optimal base, in a 1:1 mixture of H_2O/DMF as the reaction solvent at 80 ^°C for 8 h. Imidazole 2f was found to be an inexpensive, air-stable, easily available, and efficient ligand in the palladium-catalyzed Heck reactions of aryl iodides (76 %--94 %), bromides (52 %--79 %), and chlorides (40 %--70 %).


Synthesis Of Novel Imidazo[1,2-A]Pyridines And Evaluation Of Their Antifungal Activities, Füsun Göktaş, Nesri̇n Cesur, Di̇lek Şatana, Meltem Uzun Jan 2014

Synthesis Of Novel Imidazo[1,2-A]Pyridines And Evaluation Of Their Antifungal Activities, Füsun Göktaş, Nesri̇n Cesur, Di̇lek Şatana, Meltem Uzun

Turkish Journal of Chemistry

New 2-(imidazo[1,2-a]pyridin-2-ylcarbonyl)-N-substituted hydrazinecarbothioamides (4a--j), N'-(3-substituted-4-oxo-1,3-thiazolidin-2-ylidene)imidazo[1,2-a]pyridine-2-carbohydrazides (5a--f), and N-(nonsubstituted/4-substituted phenyl)-5-(imidazo[1,2-a]pyridine-2-yl)-1,3,4-oxadiazole-2-amines (6a--d) were synthesized from imidazo[1,2-a]pyridine-2-carbohydrazide (3) and evaluated for antifungal activity against Microsporum gypseum NCPF 580, M. canis, Trichophyton tonsurans NCPF 245, T. rubrum, Candida albicans ATCC 10231, and C. parapsilosis ATCC 22019 using amphotericin B as the standard. The chemical structures of the compounds were confirmed by elemental analysis, IR, ^1H NMR, ^{13}C NMR, HMBC (^{13}C, ^1H), and mass spectra. Most of the tested compounds showed moderate antifungal activity. Hydrazinecarbothioamide derivatives 4h and 4f exhibited the highest activity against M. canis (MIC: 2 \mu g mL^{-1} and 4 \mu g …


Antioxidant, Anticholinesterase, And Antimicrobial Activities And Fatty Acid Constituents Of Achillea Cappadocica Hausskn. Et Bornm., Abdulselam Ertaş, Mehmet Boğa, Nesri̇n Haşi̇mi̇, Yeter Yeşi̇l, Ahmet Ceyhan Gören, Gülaçti Topçu, Ufuk Kolak Jan 2014

Antioxidant, Anticholinesterase, And Antimicrobial Activities And Fatty Acid Constituents Of Achillea Cappadocica Hausskn. Et Bornm., Abdulselam Ertaş, Mehmet Boğa, Nesri̇n Haşi̇mi̇, Yeter Yeşi̇l, Ahmet Ceyhan Gören, Gülaçti Topçu, Ufuk Kolak

Turkish Journal of Chemistry

This study was the first fatty acid analysis and biological activity report on an endemic Achillea species, Achillea cappadocica Hausskn. et Bornm. The major compounds in the fatty acid were identified as oleic (34.7 %), palmitic (23.1 %), and linoleic acids (20.6 %). The methanol and water extracts indicated higher ABTS cation radical scavenging activity than that of \alpha-tocopherol and BHT at 100 \mu g/mL. The acetone extract showed 70.62 % inhibitory activity against butyrylcholinesterase at 200 \mu g/mL. The acetone and methanol extracts exhibited moderate antimicrobial activity.


Convenient Synthesis Of New Polysubstituted Isoindole-1,3-Dione Analogues, Ayşe Tan, Mustafa Zahri̇tti̇n Kazancioğlu, Derya Aktaş, Özlem Gündoğdu, Ertan Şahi̇n, Nurhan Ki̇shali, Yunus Kara Jan 2014

Convenient Synthesis Of New Polysubstituted Isoindole-1,3-Dione Analogues, Ayşe Tan, Mustafa Zahri̇tti̇n Kazancioğlu, Derya Aktaş, Özlem Gündoğdu, Ertan Şahi̇n, Nurhan Ki̇shali, Yunus Kara

Turkish Journal of Chemistry

Three new polysubstituted isoindole-1,3-diones were prepared from 2-ethyl-5-hydroxy-3a,4,5,7a-tetrahydro-isoindole-1,3-dione. The reaction of 2-ethyl-5-hydroxy-3a,4,5,7a-tetrahydro-isoindole-1,3-dione with m-CPBA gave the corresponding epoxide. The triacetate derivative was obtained via cis-hydroxylation using OsO_4, followed by acetylation. An aromatic derivative, a secondary reaction product, was also formed during the acetylation. Finally, a tricyclic derivative from 2-ethyl-5-hydroxy-3a,4,5,7a-tetrahydro-isoindole-1,3-dione was synthesized via dichloroketene addition under microwave irradiation. The exact structures of epoxide and tricyclic derivatives were determined by X-ray diffraction analysis.


Poly(Vinyl Chloride) Functionalization By Aliphatic And Aromatic Amines: Application To The Extraction Of Some Metal Cations, Fayçel Ammari, Faouzi Meganem Jan 2014

Poly(Vinyl Chloride) Functionalization By Aliphatic And Aromatic Amines: Application To The Extraction Of Some Metal Cations, Fayçel Ammari, Faouzi Meganem

Turkish Journal of Chemistry

The aim of this study was to evaluate the efficiency of 3 new polymers obtained by functionalization of a commercial poly(vinyl chloride) by grafting amino-alkyl and amino-aryl groups to extract some metal cations from aqueous solutions. The percentage of extraction was determined by comparing the initial electrical conductivity of the aqueous solution containing the studied metal and that of the aqueous solution at the extraction equilibrium. One of the obtained polymers gave an extraction ratio of Sn^{2+} = 87.1 %, which highlight the importance of the substitution of chlorine atoms by diethylenetriamine groups. These results were compared with those obtained …


Aqueous Dabco, An Efficient Medium For Rapid Organocatalyzed Knoevenagel Condensation And The Gewald Reaction, Mohammad Saeed Abaee, Somayeh Cheraghi Jan 2014

Aqueous Dabco, An Efficient Medium For Rapid Organocatalyzed Knoevenagel Condensation And The Gewald Reaction, Mohammad Saeed Abaee, Somayeh Cheraghi

Turkish Journal of Chemistry

In the presence of water and 1,4-diazabicyclo[2.2.2]octane, several aldehydes and cyclic ketones underwent efficient Knoevenagel condensation with malononitrile and ethyl cyanoacetate to produce the respective \alpha.\beta-unsaturated systems within fairly short time periods. As a result, high yields of conjugated products were easily obtained. Products could be engaged in a Gewald reaction, either stepwise or in situ, to produce efficiently their respective 2-aminothiophenes within 4--7 h.


Thermal Conversion Of Glycerol To Value-Added Chemicals: Pyridine Derivatives By One-Pot Microwave-Assisted Synthesis, Duygu Bayramoğlu, Gökay Gürel, Ali̇ Sinağ, Mustafa Güllü Jan 2014

Thermal Conversion Of Glycerol To Value-Added Chemicals: Pyridine Derivatives By One-Pot Microwave-Assisted Synthesis, Duygu Bayramoğlu, Gökay Gürel, Ali̇ Sinağ, Mustafa Güllü

Turkish Journal of Chemistry

One-pot syntheses of the value-added heterocyclic compounds 3-methylpyridine and pyridine using a renewable chemical, glycerol, were achieved in acidic medium by thermal conversion reactions. Condensation/cyclization reactions of the thermal degradation products of glycerol were investigated in situ using different ammonia and acidic moiety producing inorganic ammonium salts under pyrolysis or microwave heating conditions. The reaction parameters were studied in detail and satisfying product yields up to 72 % were obtained under optimized conditions. Structural identification of all compounds was accomplished by spectroscopic methods.


Qsar Study Of Chalcone Derivatives As Anti-Leishmania Agents, Maryam Iman, Asghar Davood, Nasim Banarouei Jan 2014

Qsar Study Of Chalcone Derivatives As Anti-Leishmania Agents, Maryam Iman, Asghar Davood, Nasim Banarouei

Turkish Journal of Chemistry

Quantitative structure activity relationship analyses were used to identify the ideal physicochemical characteristics of potential chalcone derivatives as anti-Leishmania agents. The HyperChem program was used to build chalcone structures and to perform conformational analyses through the semiempirical method followed by the PM3 force field. Dragon calculated a large number of molecular descriptors. Multilinear regression was used for quantitative structure activity relationship modeling. Based on our computational studies, 4 descriptors, SEigv, RDF125v, RDF055u, and O-058, can affect the activity of chalcone derivatives.


Binding Of Flavanone With \Beta-Cd/Ctdna: A Spectroscopic Investigation, Chandrasekaran Sowrirajan, Sameena Yousuf, Muthu Vijayan Enoch Israel Vijayaraj Jan 2014

Binding Of Flavanone With \Beta-Cd/Ctdna: A Spectroscopic Investigation, Chandrasekaran Sowrirajan, Sameena Yousuf, Muthu Vijayan Enoch Israel Vijayaraj

Turkish Journal of Chemistry

The inclusion complexation of flavanone with \beta-cyclodextrin was studied by ultraviolet absorption, steady state fluorescence, time-resolved fluorescence, and 2D ROESY nuclear magnetic resonance spectroscopic techniques. A 1:1 stoichiometric ratio was determined for the inclusion of flavanone with \beta-cyclodextrin. The Stern--Volmer constant for the accessible fraction of the binding of flavanone with \beta-cyclodextrin, and the binding constant for the flavanone--\beta-cyclodextrin complex are reported. The flavanone--\beta-cyclodextrin inclusion complex was characterized by 2D ROESY NMR spectroscopy. The binding of flavanone with ctDNA and the effect of \beta-cyclodextrin on the binding of flavanone to ctDNA were studied by absorption and fluorescence techniques. Binding constants …


Simultaneous Determination Of Dexpanthenol, Lidocaine Hydrochloride, And Mepyramine Maleate In Combined Pharmaceutical Gel By Capillary Electrophoresis, Gülden Akyil, Hayri̇ye Eda Şatana Kara, Sezen Yarimkaya Baş, Nusret Ertaş, Ni̇lgün Günden Göğer Jan 2014

Simultaneous Determination Of Dexpanthenol, Lidocaine Hydrochloride, And Mepyramine Maleate In Combined Pharmaceutical Gel By Capillary Electrophoresis, Gülden Akyil, Hayri̇ye Eda Şatana Kara, Sezen Yarimkaya Baş, Nusret Ertaş, Ni̇lgün Günden Göğer

Turkish Journal of Chemistry

A new capillary electrophoresis method was developed for the simultaneous determination of dexpanthenol (DEX), lidocaine (LID), and mepyramine (MEP) in pharmaceutical preparations. The best results were obtained using 20 mM (pH 3.0) phosphate buffer as the background electrolyte. Separation was obtained using a fused-silica capillary (75 \mu m internal diameter, 50 cm total length, 41 cm effective length) and a potential of +30 kV at 20 °C. Standards and samples were injected using a pressure injection at 50 mbar for 5 s and the analytes were monitored at a detection wavelength of 200 nm. Under optimum conditions, migration times were …


Ultrarapid Catalytic Reduction Of Some Dyes By Reusable Novel Erythromycin-Derived Silver Nanoparticles, Yasmeen Junejo, Abdulhadi̇ Baykal Jan 2014

Ultrarapid Catalytic Reduction Of Some Dyes By Reusable Novel Erythromycin-Derived Silver Nanoparticles, Yasmeen Junejo, Abdulhadi̇ Baykal

Turkish Journal of Chemistry

A novel green approach for the synthesis of silver nanoparticles using erythromycin as a reducing/capping agent is presented. Erythromycin-derived silver nanoparticles were characterized by ultraviolet-visible spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy, X-ray powder diffraction, and Fourier transform infrared spectroscopy. Monodispersed silver nanoparticles showed excellent and promising catalytic activity for reduction of 3 differently charged dyes (eosin B, methylene blue, and rose bengal) in the presence of NaBH_4. The study revealed that 100% reduction of these dyes can be achieved efficiently in just 150--250 s. They were easily recovered from the reaction medium and were reused 5 times, …


Synthesis And Characterization Of Magnesium Borate Minerals Of Admontite And Mcallisterite Obtained Via Ultrasonic Mixing Of Magnesium Oxide And Various Sources Of Boron: A Novel Method, Azmi̇ Seyhun Kipçak, Emek Moroydor Derun, Sabri̇ye Pi̇şki̇n Jan 2014

Synthesis And Characterization Of Magnesium Borate Minerals Of Admontite And Mcallisterite Obtained Via Ultrasonic Mixing Of Magnesium Oxide And Various Sources Of Boron: A Novel Method, Azmi̇ Seyhun Kipçak, Emek Moroydor Derun, Sabri̇ye Pi̇şki̇n

Turkish Journal of Chemistry

Magnesium borates can be used as detergent compounds or hydrocarbon catalyzers and in the ceramics industry for superconductor material manufacture owing to their high elastic coefficient and resistance to corrosion at high temperatures. In the present study, the synthesis of magnesium borate was facilitated via a novel ultrasonic method of mixing and the identification and characterization of the material were carried out via X-Ray diffraction (XRD), Fourier transform infrared (FT-IR), and Raman spectroscopies, and the B_2O_3 content was determined through titration. The surface morphology was investigated using scanning electron microscopy (SEM). The results of the XRD analysis identified the synthesized …


Synthesis, Anticandidal Activity, And Cytotoxicity Of Some Thiazole Derivatives With Dithiocarbamate Side Chains, Leyla Yurttaş, Yusuf Özkay, Fati̇h Demi̇rci̇, Gamze Göger, Şafak Ulusoylar Yildirim, Usama Abu Mohsen, Ömer Öztürk, Zafer Asim Kaplancikli Jan 2014

Synthesis, Anticandidal Activity, And Cytotoxicity Of Some Thiazole Derivatives With Dithiocarbamate Side Chains, Leyla Yurttaş, Yusuf Özkay, Fati̇h Demi̇rci̇, Gamze Göger, Şafak Ulusoylar Yildirim, Usama Abu Mohsen, Ömer Öztürk, Zafer Asim Kaplancikli

Turkish Journal of Chemistry

Some thiazole derivatives bearing dithiocarbamic acid esters were synthesized in order to investigate their anticandidal activity and cytotoxicity. The structures of the obtained final compounds (6a--j) were confirmed by spectral data (IR, ^1H NMR, ^{13}C NMR, and MS) and elemental analysis. The anticandidal activity of the compounds was determined (6a--j) using the microbroth dilution method and their cytotoxicity was evaluated according to the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay against normal cells. Contrary to expectations, weak antifungal activity was observed with IC_{50} values ranging between 30 and 403 \mu g/mL.


Performance Degradation Of Li_Xfepo_4 (X = 0, 1) Induced By Postannealing, Xiaofei Sun, Youlong Xu, Xiaoyu Zheng, Xiangfei Meng, Rui Zhang Jan 2014

Performance Degradation Of Li_Xfepo_4 (X = 0, 1) Induced By Postannealing, Xiaofei Sun, Youlong Xu, Xiaoyu Zheng, Xiangfei Meng, Rui Zhang

Turkish Journal of Chemistry

Olivine LiFePO_4 has been studied for more than a decade as a promising cathode material for rechargeable lithium batteries. However, the low electric conductivity and tap density still hinder its large-scale commercialization. Micro-sized LiFePO_4 is prepared by an optimized hydrothermal method in this paper. The influence of postannealing on the physicochemical properties of LiFePO_4 and FePO_4 is investigated to understand the plausible mechanism for performance degradation. It is found that postannealing even chemical delithiation greatly affects the particle size, morphology, pore distribution, surface area, and probably the lattice strain of Li_xFePO_4 (x = 0, 1). Consequently, the electrochemical performances of …


Synthesis Of Tertiary Propargylic Phosphonates By Addition Of Trialkynylaluminum Reagents To Acyl Phosphonates And Investigation Of Their Antimicrobial Activities, Muhammed Shakhawoat Hossain, Sidika Polat Çakir, Ayşe Betül Karaduman, Mustafa Yamaç, Ayhan Sitki Demi̇r Jan 2014

Synthesis Of Tertiary Propargylic Phosphonates By Addition Of Trialkynylaluminum Reagents To Acyl Phosphonates And Investigation Of Their Antimicrobial Activities, Muhammed Shakhawoat Hossain, Sidika Polat Çakir, Ayşe Betül Karaduman, Mustafa Yamaç, Ayhan Sitki Demi̇r

Turkish Journal of Chemistry

A series of propargylic alcohols containing phosphonates was synthesized by addition reactions of tris-(propynyl) and tris-(phenylethynyl)aluminum reagents to acyl phosphonates in good yields. Aromatic moieties of the acyl phosphonates with electron-withdrawing groups generally resulted in better isolated chemical yield. Selected propargylic phosphonates were tested for antimicrobial activities. Compounds 3a and 3h showed noticeable antifungal activity, especially against molds.


Rosmarinic Acid: A Potent Carbonic Anhydrase Isoenzymes Inhibitor, Meryem Topal, İlhami̇ Gülçi̇n Jan 2014

Rosmarinic Acid: A Potent Carbonic Anhydrase Isoenzymes Inhibitor, Meryem Topal, İlhami̇ Gülçi̇n

Turkish Journal of Chemistry

Rosmarinic acid is a water-soluble ester of caffeic acid and 3,4-dihydroxyphenyllactic acids, and is mainly found in plant species including Boraginaceae and Lamiaceae. In this research, we determined the inhibition property of rosmarinic acid on carbonic anhydrase isoenzymes I and II (hCA I and II) purified from human erythrocytes by using Sepharose-4B affinity column chromatography. hCA I and II isoenzymes were obtained with a yield of 57.9% and 67.2% and 76.5- and 509.3-fold purification of each isoenzyme, respectively. In order to show the purity of the isoenzymes, SDS-PAGE was performed and one band was observed. In vitro inhibition of both …


Electrochemistry Of Fe(Iv) And Mn(Iv) Corroles Containing Meso-Dichlorophenyl Substituents And The Use Of These Compounds As Catalysts For The Electroreduction Of Dioxygen In Acid Media, Lina Ye, Zhongping Ou, Deying Meng, Mingzhu Yuan, Yuanyuan Fang, Karl M. Kadish Jan 2014

Electrochemistry Of Fe(Iv) And Mn(Iv) Corroles Containing Meso-Dichlorophenyl Substituents And The Use Of These Compounds As Catalysts For The Electroreduction Of Dioxygen In Acid Media, Lina Ye, Zhongping Ou, Deying Meng, Mingzhu Yuan, Yuanyuan Fang, Karl M. Kadish

Turkish Journal of Chemistry

Two meso-dichlorophenyl substituted metallocorroles were synthesized and characterized as to their electrochemical and spectroelectrochemical properties in dichloromethane, benzonitrile, and pyridine containing 0.1 M tetra-n-butylammonium perchlorate (TBAP) as supporting electrolyte. The examined compounds are represented as (Cl_2Ph)_3CorFe^{IV}Cl and (Cl_2Ph)_3CorMn^{IV}Cl where (Cl_2Ph)_3Cor is the trianion of 5,10,15-tri(2,4-dichlorophenyl)corrole. Each metallocorrole was examined as to its catalytic activity for the electoreduction of dioxygen when coated on an edge-plane pyrolytic graphite electrode in 1.0 M HClO_4. Cyclic voltammetry combined with linear sweep voltammetry at a rotating disk electrode (RDE) and a rotating ring disk electrode (RRDE) was utilized to evaluate the catalytic activity for the …


Td-Dft Calculations And Mcd Spectroscopy Of Porphyrin And Phthalocyanine Analogues: Rational Design Of Photosensitizers For Pdt And Nir Region Sensor Applications, John Mack, Martijn Wildervanck, Tebello Nyokong Jan 2014

Td-Dft Calculations And Mcd Spectroscopy Of Porphyrin And Phthalocyanine Analogues: Rational Design Of Photosensitizers For Pdt And Nir Region Sensor Applications, John Mack, Martijn Wildervanck, Tebello Nyokong

Turkish Journal of Chemistry

Geometry optimizations and TD-DFT calculations have been carried out on series of fused-ring-expanded phthalonitriles, phthalocyanines, and aza-dipyrromethene boron difluoride (aza-BODIPY) dyes and trends in their optical and redox properties have been analyzed. The potential utility of fused-ring-expanded phthalocyanine and aza-BODIPY analogues for photodynamic therapy and near infrared region sensor applications is assessed on this basis. Recent attempts to prepare fused-ring-expanded aza-BODIPY analogues with benzene, pyrazine, and naphthalene rings have demonstrated that the properties of aza-BODIPYs vary markedly when different fused ring systems are added to the \beta-carbons of the pyrrole rings. A comparison of the TD-DFT calculations demonstrates that, as …