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Full-Text Articles in Physical Sciences and Mathematics

Copolymerization Of N-Vinyl Pyrrolidone With Methyl Methacrylate By Ti(Iii)-Dmg Redox Initiator, Ajithkumar Manayan Parambil, Yashoda Malagar Puttaiahgowda, Prasannakumar Shankarappa Jan 2012

Copolymerization Of N-Vinyl Pyrrolidone With Methyl Methacrylate By Ti(Iii)-Dmg Redox Initiator, Ajithkumar Manayan Parambil, Yashoda Malagar Puttaiahgowda, Prasannakumar Shankarappa

Turkish Journal of Chemistry

Redox copolymerization of N-vinyl-2-pyrrolidone (NVP) with methyl methacrylate (MMA) was carried out using titanium(III)-- dimethylglyoxime [Ti(III)-DMG] redox initiator in aqueous sulfuric acid-alcohol media. The resulting copolymer was characterized by FTIR, ^1H-NMR, and ^{13}C-NMR spectroscopic methods and elemental analysis. Thermal properties of the copolymer were determined by differential scanning calorimetric technique and thermogravimetric analysis. The reactivity ratios of the monomers were computed by Fineman-Ross, Kelen-Tudos, and extended Kelen-Tudos methods at lower conversion. The reactivity ratios obtained r_1 (MMA) 1.69 and r_2 (NVP) 0.03 showed richer content of MMA than NVP in the copolymer having extreme ideal behavior. The distribution of monomer …


Design And Synthesis Of New 1,2,4-Triazole Derivatives Containing Morpholine Moiety As Antimicrobial Agents, Deni̇z Şahi̇n, Hacer Bayrak, Ahmet Demi̇rbaş, Nesli̇han Demi̇rbaş, Şengül Alpay Karaoğlu Jan 2012

Design And Synthesis Of New 1,2,4-Triazole Derivatives Containing Morpholine Moiety As Antimicrobial Agents, Deni̇z Şahi̇n, Hacer Bayrak, Ahmet Demi̇rbaş, Nesli̇han Demi̇rbaş, Şengül Alpay Karaoğlu

Turkish Journal of Chemistry

2-Morpholine-4ylethyl-3H-1,2,4-triazole-3-ones (2a, 2b) were obtained from the condensation between the corresponding ethoxycarbonylhydrazones and 2-morpholinoethanamine. 2a was converted to acetohydrazide (4) via the formation of an ester derivative (3). Treatment of 2a and 2b with several aryl sulfonyl chlorides afforded the corresponding 2-arylsulfonyl-1,2,4-triazole-3-ones (5a-c and 6). The reaction of hydrazide (4) with benzyl iso- and benzyl isothiocyanate produced the corresponding carboxamide (8a) and carbothioamide (8b). The basic treatment of 8b yielded 5-mercapto-4H-1,2,4-triazol-3-yl)methyl]-2,4-dihydro-3H-1,2,4-triazol-3-one (10). The synthesis of 1,3-thiazol-2(3H)-ylidene-1,2,4-triazol-1- ylacetohydrazide (11) and 1,3-oxazole-2(3H)-ylidene-1,2,4-triazole- 1-yl)acetohydrazide (9) derivatives was performed from the reaction of 8a and 8b with substituted phenacyl bromides. All the newly synthesized …


Titrimetric Determination Of Anionic Surfactant Content In Anionic/Nonionic Surfactant Mixture Solution By Anionic Surfactant Selective Electrode, Junwei Wang, Zhiping Du, Wanxu Wang, Wei Xue Jan 2012

Titrimetric Determination Of Anionic Surfactant Content In Anionic/Nonionic Surfactant Mixture Solution By Anionic Surfactant Selective Electrode, Junwei Wang, Zhiping Du, Wanxu Wang, Wei Xue

Turkish Journal of Chemistry

A new polyvinyl chloride (PVC) membrane electrode for determining the concentration of sodium dodecylsulfate (SDS) based on a neutral ion pair complex of dodecyltrimethylammonium-dodecylsulfate (DTA^+DS^-) as ionophore is described in this paper. The construction and characteristic performance of the PVC membrane electrode displays a Nernstian slope of --56.9 \pm 0.3 mV/decade in the concentration range of 2.0 \times 10^{-6} to 3.2 \times 10^{-3} mol L^{-1} and a detection limit of 1.6 \times 10^{-6} mol L^{-1}. The lifetime of the electrode is more than 3 months without showing significant change in the values of slope or linear concentration range. The electrode …


Facile And Rapid Synthesis Of Some Novel Polysubstituted Imidazoles By Employing Magnetic Fe_3o_4 Nanoparticles As A High Efficient Catalyst, Bahador Karami, Khalil Eskandari, Abdolmohammad Ghasemi Jan 2012

Facile And Rapid Synthesis Of Some Novel Polysubstituted Imidazoles By Employing Magnetic Fe_3o_4 Nanoparticles As A High Efficient Catalyst, Bahador Karami, Khalil Eskandari, Abdolmohammad Ghasemi

Turkish Journal of Chemistry

Multicomponent, one-pot, highly efficient, and environmentally adapted synthesis of some novel polysubstituted imidazoles by the use of various aldehydes, benzil, aliphatic, and aromatic primary amines and ammonium acetate in the presence of Fe_3O_4 nanoparticles as catalyst under solvent-free condition is explained. A highly efficient role of Fe_3O_4 nanoparticles as catalyst in this synthesis was shown. By this advantage, several polysubstituted imidazoles as pharmaceutical important molecules can be prepared in high yield and high purity. This method is very easy and rapid for the synthesis of imidazole derivatives. All products were deduced from their IR and NMR spectroscopic data. The Fe_3O_4 …


Determination Of Ultratrace Amounts Of Dichloro-Nitrobenzene And Dichloro-Nitroaniline In Water Samples Using Solidified Floating Organic Drop Microextraction (Sfodme) And Gas Chromatography, Shayessteh Dadfarnia, Mohammad Mirzaei, Ali Mohammad Haji Shabani, Batoul Ramazanzadeh Jan 2012

Determination Of Ultratrace Amounts Of Dichloro-Nitrobenzene And Dichloro-Nitroaniline In Water Samples Using Solidified Floating Organic Drop Microextraction (Sfodme) And Gas Chromatography, Shayessteh Dadfarnia, Mohammad Mirzaei, Ali Mohammad Haji Shabani, Batoul Ramazanzadeh

Turkish Journal of Chemistry

Solidified floating organic drop microextraction (SFODME) in combination with gas chromatography with an electron capture detector was used for separation/enrichment and determination of 2,5-dichloro-nitrobenzene, 2,3-dichloro-nitrobenzene, and 2,6-dichloro-4-nitroaniline in water samples. The main parameters affecting the performance of SFOME, such as solvent volume, extraction time, stirring rate, extraction temperature, sample volume, nature of the solvent and ionic strength were optimized. Under the optimum experimental conditions, good relative standard deviations of 7.5%, 6.9%, and 9.3% for 7 extractions and determination of 50 ng L^{-1} of 2,5-dichloro-nitrobenzene, 2,3-dichloro-nitrobenzene and 2,6-dichloro-4-nitroaniline were obtained, respectively. Enrichment factors of 1390, 1398, and 1362 and detection limits …


Synthesis And Application Of L-Proline And R-Phenylglycine Derived Organocatalysts For Direct Asymmetric Michael Addition Of Cyclohexanone To Nitroalkenes, Hayri̇ye Nevi̇n Naziroğlu, Abdulkadi̇r Sirit Jan 2012

Synthesis And Application Of L-Proline And R-Phenylglycine Derived Organocatalysts For Direct Asymmetric Michael Addition Of Cyclohexanone To Nitroalkenes, Hayri̇ye Nevi̇n Naziroğlu, Abdulkadi̇r Sirit

Turkish Journal of Chemistry

Novel R-phenylglycine derived organocatalysts were prepared from the reaction of Cbz-R-phenylglycine with indoline, pyrrolidine, or (S)-(-)-2-(diphenylmethyl)pyrrolidine in 3 steps. The asymmetric Michael addition of cyclohexanone to nitroolefins was investigated using R-phenylglycine derivatives along with L-prolinamides as chiral catalysts. The desired products were obtained in excellent yields with enantioselectivities up to 90% ee and diastereomeric ratio up to 98:2 of the syn }addition product.


A One-Pot Efficient Four-Component Reaction For The Synthesis Of 2-(Arylamino)-2-(5-Aryl-1-Ethenyl-1,3,4-Oxadiazol-2-Yl)Propyl Benzoate (Or 4-Bromobenzoate) Derivatives, Mohsen Valizadeh Holagh, Abel Mohammadali Oglu Maharramov, Mirza Aliakbar Oglu Allahverdiyev, Ali Ramazani, Yavar Ahmadi, Fatemeh Zeinali Nasrabadi, Ali Souldozi Jan 2012

A One-Pot Efficient Four-Component Reaction For The Synthesis Of 2-(Arylamino)-2-(5-Aryl-1-Ethenyl-1,3,4-Oxadiazol-2-Yl)Propyl Benzoate (Or 4-Bromobenzoate) Derivatives, Mohsen Valizadeh Holagh, Abel Mohammadali Oglu Maharramov, Mirza Aliakbar Oglu Allahverdiyev, Ali Ramazani, Yavar Ahmadi, Fatemeh Zeinali Nasrabadi, Ali Souldozi

Turkish Journal of Chemistry

Reactions of N-isocyaniminotriphenylphosphorane with 2-oxopropyl benzoate (or 2-oxopropyl 4-bromobenzoate) in the presence of 3-phenyl-2-propynoic acid and primary amines proceeded smoothly at room temperature and in neutral conditions to afford sterically congested 1,3,4-oxadiazole derivatives in high yields. The reaction proceeded smoothly and cleanly under mild conditions and no side reactions were observed.


Synthesis And Characterization Of Bis(Azine) Ligands And Metal Complexes: Dna-Interaction And Extraction Properties For Metals And Dichromate Anions, Sultan Kulaksizoğlu, Cansu Gökçe, Ramazan Güp Jan 2012

Synthesis And Characterization Of Bis(Azine) Ligands And Metal Complexes: Dna-Interaction And Extraction Properties For Metals And Dichromate Anions, Sultan Kulaksizoğlu, Cansu Gökçe, Ramazan Güp

Turkish Journal of Chemistry

Two new bis(bidentate) azine ligands were prepared by linking (1Z,1'Z)-1,1'-{butane-1,4-diylbis[oxyben-zene-4,1- diyl(1Z)eth-1-yl-1-ylidene]}dihydrazine to salicylaldehyde and pyridine-2-carbaldehyde, 1,4-bis{4-{(1E)-1-((2E)-(2- hydroxybenzene--2-ylmethy-lidene)hydrazonylidene)ethyl}phenoxy}butane (H_2L^1), and 1,4-bis{4-{(1E)-1-((2E)-(pyridine--2-ylmethylidene) hydrazonylidene)ethyl}phenoxy}butane (L^2), respecti- vely. Two kinds of copper(II) and nickel(II) complexes with different ligands were prepared. Reaction of H_2L^1 with Cu(II) and Ni(II) acetate with 1:1 molar ratio gave double stranded binuclear bis(azine) complexes with stoichiometry [M(L^1)]_2 containing {M^{II}N_2O_2} centers. On the other hand, 1:1 molar ratio reaction of Cu(II) and Ni(II) chloride with L^2 yielded mononuclear metal complexes with general stoichiometry [M(L^2)Cl_2] containing {M^{II}N_2N_2} centers. The structures of both bis(azine) ligands and complexes were identified by elemental analysis, infrared …


Chemical And Biotransformation Of Gelomulide F: A Rare Diterpene Lactone, Humaira Yasmeen Gondal, Muhammad Iqbal Choudhary Jan 2012

Chemical And Biotransformation Of Gelomulide F: A Rare Diterpene Lactone, Humaira Yasmeen Gondal, Muhammad Iqbal Choudhary

Turkish Journal of Chemistry

Chemical and biotransformations of a rare diterpene lactone, Gelomulide F (1), from the cytotoxic extract of leaves of Suregada multiflora were studied. Fermentation of compound 1 with Sachromyces cerevisiae transformed it to Gelomulide D (2) and E (3), whereas its treatment with 2N KOH yielded Gelomulide D (2). In addition, a novel compound (4) was obtained by its diastereo and chemoselective reduction with NaBH_4. All of these compounds were characterized on the basis of extensive ^1H-NMR, ^{13}C-NMR, 2D NMR, and mass spectral analyses.


Synthesis And Antioxidant And Antimicrobial Evaluation Of Novel 4-Substituted-1h-1,2,4-Triazole Derivatives, Sultan Baytaş, Evi̇n Kapçak, Tülay Çoban, Hati̇ce Özbi̇lge Jan 2012

Synthesis And Antioxidant And Antimicrobial Evaluation Of Novel 4-Substituted-1h-1,2,4-Triazole Derivatives, Sultan Baytaş, Evi̇n Kapçak, Tülay Çoban, Hati̇ce Özbi̇lge

Turkish Journal of Chemistry

A series of 4-benzyl/phenyl-3-(1-methyl-1H-indole-2-yl)-1H- 1,2,4-triazole-5(4H)-thione (4a,b) and 2-{4-[benzyl/phenyl-5- (substitutedbenzylthio)]-4H-1,2,4-triazole-3-yl}-1-methyl-1H-indole derivatives (5a-p) were synthesized and evaluated for their in vitro scavenging of DPPH and superoxide radical, and lipid peroxidation inhibition effects as well as their antimicrobial properties. DPPH radical scavenging capacity was found to be equipotent with BHT and found in compounds containing 1,2,4-triazole-5(4H)-thione moiety (4a,b). With regard to antimicrobial properties, compound 5k showed slight antimicrobial activity against all the test microorganisms.


Mwcnt/Nano-Zro_2 As A New Solid Phase Extractor: Its Synthesis, Characterization, And Application To Atomic Absorption Spectrometric Determination Of Lead, Orhan Murat Kalfa, Özcan Yalçinkaya, Ali̇ Rehber Türker Jan 2012

Mwcnt/Nano-Zro_2 As A New Solid Phase Extractor: Its Synthesis, Characterization, And Application To Atomic Absorption Spectrometric Determination Of Lead, Orhan Murat Kalfa, Özcan Yalçinkaya, Ali̇ Rehber Türker

Turkish Journal of Chemistry

Nanoscale ZrO_2 was synthesized on a multiwall carbon nanotube (MWCNT) and designed as a new solid phase extractor for metal ion preconcentration. The characterization of the synthesized material was achieved by transmission electron microscope (TEM) and X-ray diffraction (XRD). Then the new nanoscale material was applied to preconcentration of lead(II) from various matrices. Different experimental factors including pH of the sample solution, sample volume, flow rate of the sample solution, and volume and concentration of the eluent for the preconcentration step were examined. The effect of interfering ions on the recovery of the lead(II) was also investigated. The recovery of …


Synthesis And Structural And Electrochemical Characterization Of Novel Macrocyclic Vic-Dioxime Ligand And Its Mononuclear Transition And Nontransition Metal Complexes, Pervi̇n Deveci̇, Bi̇lge Taner, Zeynel Kiliç, Ali̇ Osman Solak, Emi̇ne Özcan Jan 2012

Synthesis And Structural And Electrochemical Characterization Of Novel Macrocyclic Vic-Dioxime Ligand And Its Mononuclear Transition And Nontransition Metal Complexes, Pervi̇n Deveci̇, Bi̇lge Taner, Zeynel Kiliç, Ali̇ Osman Solak, Emi̇ne Özcan

Turkish Journal of Chemistry

The reaction of N-(4-aminophenyl)aza-15-crown-5 (1) with anti-chlorophenylglyoxime (2) produces a novel azacrown ether containing vic-dioxime, N-(4-aminophenyl)aza-15-crown-5-phenylglyoxime (LH_2). LH_2 reacts with Ni(II), Cu(II), Co(II), Cd(II), and Zn(II) ions to yield the mononuclear transition and nontransition metal complexes [M(LH)_2] (M = Ni and Cu), [M(LH)_2(H_2O)_2] (M = Co), and [M(LH)(H_2O)(Cl)] (M = Cd and Zn). The structural features of LH_2 were studied using several techniques including elemental analysis, Fourier transform infrared spectroscopy (FT-IR), ultraviolet visible (UV-Vis), mass spectrometry (MS), 1-dimensional (1D) ^1H-NMR and ^{13}CNMR, distortionless enhancement by polarization transfer (DEPT) 2-dimensional (2D) heteronuclear single-quantum coherence (HSQC), and heteronuclear multiple-bond correlation (HMBC) techniques. …


Synthesis And Chemical Transformations Of Azonine Derivatives, Ahmed A. Fadda, Elsayed M. Afsah, Samir Bondock, Mohamed M. Hammouda Jan 2012

Synthesis And Chemical Transformations Of Azonine Derivatives, Ahmed A. Fadda, Elsayed M. Afsah, Samir Bondock, Mohamed M. Hammouda

Turkish Journal of Chemistry

No abstract provided.


Synthesis Of Linezolid-Like Molecules And Evaluation Of Their Antimicrobial Activities, Serap Başoğlu, Meltem Yolal, Ahmet Demi̇rbaş, Hakan Bektaş, Rza Abbasoğlu, Nesli̇han Demi̇rbaş Jan 2012

Synthesis Of Linezolid-Like Molecules And Evaluation Of Their Antimicrobial Activities, Serap Başoğlu, Meltem Yolal, Ahmet Demi̇rbaş, Hakan Bektaş, Rza Abbasoğlu, Nesli̇han Demi̇rbaş

Turkish Journal of Chemistry

3-Fluoro-4-(morpholin-4-yl)aniline (2), prepared from 3,4-difluoronitrobenzene, was converted to the corresponding Schiff base (3) by treatment with indol-3-carbaldehyde. The treatment of thiourea 4 and carbothioamide derivatives 9 with ethyl bromoacetate or 4-substituted phenacyl bromides generated the corresponding thiazolidinone (5 and 13) and thiazoline (6 and 12) derivatives, respectively. The acidic or basic treatment of carbothioamide 9 produced 1,3,4-thiadiazole (11) or 1,2,4-triazole (10) compounds, respectively. The structural assignments of the new compounds were based on elemental analysis and spectral (IR, ^1H-NMR, ^{13}C-NMR, and LC-MS) data. The antimicrobial activity study revealed that all compounds showed good antitubercular activities.


Ni_{55} Nanocluster: A Density Functional Theory Study Of The Binding Energy Of Nickel And Ethylene Adsorption, Nusret Duygu Yilmazer, Mehmet Ferdi̇ Fellah, Işik Önal Jan 2012

Ni_{55} Nanocluster: A Density Functional Theory Study Of The Binding Energy Of Nickel And Ethylene Adsorption, Nusret Duygu Yilmazer, Mehmet Ferdi̇ Fellah, Işik Önal

Turkish Journal of Chemistry

Ethylene adsorption on a Ni_{55} nanocluster was studied by means of the density functional theory (DFT)/B3LYP using the basis sets of 6-31G(d,p) and 86-411(41d)G in Gaussian 03. The Ni_{55} nanocluster was found to have a distorted icosahedral geometry, in accordance with the experimental findings. The binding energy value for the Ni_{55} nanocluster was calculated to be 3.51 eV/atom using equilibrium geometry calculations. The estimated bulk nickel binding energy was in reasonable agreement with the experimental value (4.85 versus 4.45 eV/atom). In addition, equilibrium geometry calculations were performed for ethylene adsorption on the Ni_{55} nanocluster for 2 different coordination numbers of …


Synthesis And Characterization Of Transition Metal Coordination Polymers Derived From 1,4-Benzenedicarboxylate And Certain Azoles, Aref A. M. Aly, Mahmoud Ghandour, Maged S. Alfakeh Jan 2012

Synthesis And Characterization Of Transition Metal Coordination Polymers Derived From 1,4-Benzenedicarboxylate And Certain Azoles, Aref A. M. Aly, Mahmoud Ghandour, Maged S. Alfakeh

Turkish Journal of Chemistry

A series of coordination polymers of the general formula {[M(BDC)(azoles)(H_2O)_m].xH_2O}_n (where M = Co(II), Ni(II), and Cu(II); BDC = 1,4-benzenedicarboxylate; azoles = 2-aminobenzothiazole, 2-aminothiazole, and 2-amino-4-methyl-thiazole; m = 0 or 1; and x = 1 or 2) were prepared and characterized. The complexes were characterized based on elemental analysis, infrared and electronic spectral studies, magnetic measurements, molar conductance, thermal analysis, X-ray diffraction, scanning electron microscopy, and biological activity. Thermogravimetry, derivative thermogravimetry, and differential thermal analysis were used to study the thermal decomposition of the complexes. The kinetic parameters were calculated making use of the Coats-Redfern and Horowitz-Metzger equations.


Hydrothermal Synthesis And Characterization Of Nanosized Transition Metal Chromite Spinels, Shahid Khan Durrani, Syed Zahid Hussain, Khalid Saeed, Yaqoob Khan, Mohammad Arif, Nisar Ahmed Jan 2012

Hydrothermal Synthesis And Characterization Of Nanosized Transition Metal Chromite Spinels, Shahid Khan Durrani, Syed Zahid Hussain, Khalid Saeed, Yaqoob Khan, Mohammad Arif, Nisar Ahmed

Turkish Journal of Chemistry

Homogeneous crystalline transition metal chromite spinels (MCr_2O_4, where M = Co, Mn, and Ni) were prepared by hydrothermal reaction of aqueous solutions containing the respective metal nitrate, chromium(III) nitrate, and sodium hydroxide in stoichiometric amounts at 180-200 °C and pH 10.5-11.5 for 11-13 h. The crystalline structure, microstructure, and thermal stability of the synthesized chromite products were analyzed by X-ray diffraction (XRD), scanning electron microscopy, thermogravimetry, and differential thermal analysis. The analysis results revealed that the CoCr_2O_4 and MnCr_2O_4 crystalline phases were thermally stable in the range of 750-800 °C. UV-visible studies showed that higher characteristic bands corresponded to the …


Solvent-Free Michael Addition Of 2-Cyclohexenone Under Ultrasonic Irradiation In The Presence Of Long Chain Dicationic Ammonium Salts, Aytek Öge, Murat Emrah Mavi̇ş, Çi̇ğdem Yolaçan, Feray Aydoğan Jan 2012

Solvent-Free Michael Addition Of 2-Cyclohexenone Under Ultrasonic Irradiation In The Presence Of Long Chain Dicationic Ammonium Salts, Aytek Öge, Murat Emrah Mavi̇ş, Çi̇ğdem Yolaçan, Feray Aydoğan

Turkish Journal of Chemistry

Long chain dicationic ammonium salts (1a-1c), easily prepared from tert-amines and dihaloalkanes, were successfully used as efficient phase-transfer catalysts in the Michael addition reaction of various active methylene compounds to 2-cyclohexenone without solvent under ultrasonic irradiation. The investigated dicationic salts were more effective than monocationic tetrabutylammonium bromide, with short reaction times and high yields. This methodology was established under phase-transfer catalytic conditions and ultrasonic effects with many advantages, including the easy and cost-effective synthesis of the catalyst, mild reaction conditions, short reaction times, good yields, simple work-up procedures, and environmental friendliness.


One-Pot Synthesis Of Fully Substituted 1,3,4-Oxadiazole Derivatives From Aromatic Carboxylic Acids, Cyclobutanone And N-Isocyaniminotriphenylphosphorane, Mohsen Valizadeh Holagh, Abel Mohammadali Oglu Maharramv, Mirza Aliakbar Oglu Allahverdiyev, Ali Ramazani, Yavar Ahmadi, Ali Souldozi Jan 2012

One-Pot Synthesis Of Fully Substituted 1,3,4-Oxadiazole Derivatives From Aromatic Carboxylic Acids, Cyclobutanone And N-Isocyaniminotriphenylphosphorane, Mohsen Valizadeh Holagh, Abel Mohammadali Oglu Maharramv, Mirza Aliakbar Oglu Allahverdiyev, Ali Ramazani, Yavar Ahmadi, Ali Souldozi

Turkish Journal of Chemistry

Reactions of N-isocyaniminotriphenylphosphorane with cyclobutanone in the presence of aromatic (or heteroaromatic) carboxylic acids proceeded smoothly at room temperature and in neutral conditions to afford sterically congested 1-(5-aryl-1,3,4-oxadiazol-2-yl)- 1-cyclobutanol derivatives in high yields. The reaction proceeded smoothly and cleanly under mild conditions and no side reactions were observed. The structures of the products were deduced from their IR, ^1HNMR, and ^{13}CNMR spectra, and mass spectrometry.


Synthesis, Characterization, And Antimicrobial Activity Of A New Pyrimidine Schiff Base And Its Cu(Ii), Ni(Ii), Co(Ii), Pt(Ii), And Pd(Ii) Complexes, Mehmet Gülcan, Mehmet Sönmez, İsmet Berber Jan 2012

Synthesis, Characterization, And Antimicrobial Activity Of A New Pyrimidine Schiff Base And Its Cu(Ii), Ni(Ii), Co(Ii), Pt(Ii), And Pd(Ii) Complexes, Mehmet Gülcan, Mehmet Sönmez, İsmet Berber

Turkish Journal of Chemistry

A new Schiff base, {1-[(5-bromo-2-hydroxy-benzylidene)- amino]-4-phenyl-2-thioxo-1,2-dihyro-pyrimidin-5-yl}-phenyl-methanone, was synthesized from N-amino pyrimidine-2-thione and 5-bromsalicylaldehyde. Metal complexes of the Schiff base were prepared from acetate salts of Cu(II), Ni(II), Co(II), Pd(II), and PtCl_2 in methanol. The chemical structures of the Schiff base ligand and its metal complexes were confirmed by spectroscopic analysis. All of the compounds were evaluated for their antimicrobial against 4 gram-positive bacteria, 1 gram-negative bacterium, and 3 yeast strains. The Schiff base and the Cu(II) and Co(II) complexes showed good biological activity against all tested bacteria and yeast strains.


Theory Of Adsorption Equilibria Analysis Based On General Equilibrium Constant Expression, Abdul Sattar Ali Khan Jan 2012

Theory Of Adsorption Equilibria Analysis Based On General Equilibrium Constant Expression, Abdul Sattar Ali Khan

Turkish Journal of Chemistry

Adsorption equilibria were analyzed on the basis of general equilibrium constant expression for the development of fundamental adsorption equations (Freundlich, Langmuir, and BET) in connection with the establishment of a general approach towards physical interpretations of adsorption parameters. Theoretically it was proved that Freundlich plot analysis cannot be used to find useful parameters such as the monolayer adsorption capacity of an adsorbent. The present theory also indicated that the adsorption process with known value of monolayer adsorption capacity can be studied for finding various equilibrium constants on the basis of the Fronaeus equation, which is commonly used in the complexation …


Determination Of Cadmium In High Salt Content Matrices By Flow Injection Cold Vapor Atomic Absorption Spectrometry, Orkun Alp, Hakan Demi̇röz, Osman Yavuz Ataman, Nusret Ertaş Jan 2012

Determination Of Cadmium In High Salt Content Matrices By Flow Injection Cold Vapor Atomic Absorption Spectrometry, Orkun Alp, Hakan Demi̇röz, Osman Yavuz Ataman, Nusret Ertaş

Turkish Journal of Chemistry

Flow injection cold vapor atomic absorption spectrometry (FI-CVAAS) was used for determination of cadmium in high salt matrices such as dialysis concentrates and textile leach solutions. The parameters such as acidity, concentration of reducing agent, reaction coil length, and carrier gas flow rate were investigated to obtain the best sensitivity. No significant background signal was observed even at high salt concentrations. Under the optimized conditions the limit of detection value (3s_b m^{-1}, where s_b is the standard deviation of the blank signals and m is the slope of the calibration graph) was found to be 0.05 ng mL^{-1} for an …


^{99m}Tc Labeled Levofloxacin As An Infection Imaging Agent: A Novel Method For Labeling Levofloxacin Using Cysteine\Cdot Hcl As Co-Ligand And In Vivo Study, Syed Ali Raza Naqvi, Malik Muhammad Ishfaq, Zulfiqar Ali Khan, Saeed Ahmad Nagra, Iftikhar Hussain Bukhari, Abdullah Ijaz Hussain, Nasir Mahmood, Sohail Anjum Shahzad, Asma Haque, Tanveer Hussain Bokhari Jan 2012

^{99m}Tc Labeled Levofloxacin As An Infection Imaging Agent: A Novel Method For Labeling Levofloxacin Using Cysteine\Cdot Hcl As Co-Ligand And In Vivo Study, Syed Ali Raza Naqvi, Malik Muhammad Ishfaq, Zulfiqar Ali Khan, Saeed Ahmad Nagra, Iftikhar Hussain Bukhari, Abdullah Ijaz Hussain, Nasir Mahmood, Sohail Anjum Shahzad, Asma Haque, Tanveer Hussain Bokhari

Turkish Journal of Chemistry

Levofloxacin was labeled with ^{99m}Tc using cysteine\cdot HCl as co-ligand and SnCl_2.2H_2O as reducing agent. The influence of various parameters such as amount of cysteine\cdot HCl, reducing agent, pH value, and reaction time on labeling process was studied. After optimizing the conditions the labeling was performed at pH 5 using 1 mg of levofloxacin, 500 \mu g of cysteine\cdot HCl, 50 \mu g of SnCl_2.2H_2O, and 15 min reaction time. The radiochemical purity was determined with the help of instant thin layer chromatography (ITLC) and reverse phase high performance liquid chromatography (RP-HPLC) which was more than 95% and was stable …


Synthesis Of Some New Urea And Thiourea Derivatives And Evaluation Of Their Antimicrobial Activities, Yildiz Gülkok, Tuba Bi̇çer, Fatma Kaynak Onurdağ, Selda Özgen, Mustafa Fethi̇ Şahi̇n, Deni̇z Songül Doğruer Jan 2012

Synthesis Of Some New Urea And Thiourea Derivatives And Evaluation Of Their Antimicrobial Activities, Yildiz Gülkok, Tuba Bi̇çer, Fatma Kaynak Onurdağ, Selda Özgen, Mustafa Fethi̇ Şahi̇n, Deni̇z Songül Doğruer

Turkish Journal of Chemistry

In the present study, 18 new compounds were synthesized, 9 of which were urea (9a-e, 10a-d) while the others were thiourea (11a-e, 12a-d) derivatives. These derivatives were prepared by the reaction of 6-amino-5-nonsubstituted/chloro-3-methyl-2(3H)- benzoxazolones used as key intermediates with the appropriate isocyanates and isothiocyanates. The chemical structures of new compounds were confirmed by ^1H-NMR, mass, and elemental analysis. The synthesized compounds were screened for their antibacterial and antifungal activities against some pathogenic strains. Compounds 9a, 9b, 9e, 10a, and 10c, urea derivatives, and compounds 12a and 12d, thiourea derivatives, exhibited a relatively good inhibitory profile against E. coli, with a …


Antimicrobial Properties And Dna Interactions Studies Of 3-Hetarylazoquinoline-2,4-Diol Compounds, Fatma Öztürk, Leyla Açik, İzzet Şener, Fi̇kret Karci, Emi̇ne Kiliç Jan 2012

Antimicrobial Properties And Dna Interactions Studies Of 3-Hetarylazoquinoline-2,4-Diol Compounds, Fatma Öztürk, Leyla Açik, İzzet Şener, Fi̇kret Karci, Emi̇ne Kiliç

Turkish Journal of Chemistry

The purpose of the present study was to evaluate the antimicrobial effects of 3-hetarylazoquinoline-2,4-diols (19), having substituted or unsubstituted thiazole, benzothiazole, benzimidazole, triazole, isoxazole, and thiadiazole moieties at the 3-position, on bacterial and yeast strains. In addition, compounds and DNA interaction with pUC18 plasmid DNA were studied. The biological effects of these molecules were compared with potential antibiotics ampicillin,~chloramfenicol (for bacteria), and ketoconozole (for yeast). According to the results, all compounds except 8 have mild to moderate activity against some of the bacterial strains tested, and none of the compounds have activity against the fungi C. tropicalis and C. albicans. …


Influence Of Reaction Parameters On The Synthesis Of Surfactant-Assisted Tin Oxide Nanoparticles, Muhammad Akhyar Farrukh, Prisca Tan, Rohana Adnan Jan 2012

Influence Of Reaction Parameters On The Synthesis Of Surfactant-Assisted Tin Oxide Nanoparticles, Muhammad Akhyar Farrukh, Prisca Tan, Rohana Adnan

Turkish Journal of Chemistry

Tin oxide nanoparticles were synthesized via hydrothermal method using a non-ionic surfactant, oleyl amine (OLM), in the presence of urea. The reactions were carried out at different calcination temperatures and varying concentrations of surfactant and urea. The effect of these reaction parameters on the particles' size, distribution, surface area, and the average pore diameter were investigated using X-ray diffraction analysis, transmission electron microscopy, scanning electron microscopy, energy dispersive X-ray analysis, thermogravimetric analysis, Brunauer-Emmett-Teller method, and Fourier transform infrared spectroscopy. Larger tin oxide nanoparticles were obtained with higher concentrations of urea. At the optimum experimental conditions, tin oxide nanoparticles with mean …


Polymers From Renewable Resources: Synthesis And Characterization Of Poly(2,5-Dihydro-2,5-Dimethoxy Furan), Hakan Çi̇ftçi̇, Zeki̇ Öktem, Hasan Nur Testereci̇ Jan 2012

Polymers From Renewable Resources: Synthesis And Characterization Of Poly(2,5-Dihydro-2,5-Dimethoxy Furan), Hakan Çi̇ftçi̇, Zeki̇ Öktem, Hasan Nur Testereci̇

Turkish Journal of Chemistry

The cationic polymerization of cis, trans-2,5-dihydro-2,5-dimethoxy furan (DHMF) was studied in the presence of HClO_4, in acetonitrile. Different reaction parameters were investigated such as initiator concentration and temperature with duration. Obtained polymers were soluble in dimethylsulfoxide (DMSO) and dimethylformamide (DMF) and the M_n value was calculated as 2700 g/mol by cryoscopy. The FT-IR and ^1H-NMR results indicate that the polymerization proceeds via ring opening. Thermal properties were studied by DSC and TGA.


Novel Biologically Active Glycosides From The Aerial Parts Of Cephalaria Gazipashensis, Nazli Böke Sarikahya, Süheyla Kirmizigül Jan 2012

Novel Biologically Active Glycosides From The Aerial Parts Of Cephalaria Gazipashensis, Nazli Böke Sarikahya, Süheyla Kirmizigül

Turkish Journal of Chemistry

Two new triterpene glycosides, 3-O-\beta-D-glucopyranosyl- (1\to 4)-\beta-D-xylopyranosyl-(1\to 3)-\alpha-L-rhamnopyranosyl- (1\to 3)-\alpha-L-arabinopyranosyl olean-12-ene 28-O-\beta -D- glucopyranosyl-(1\to 6)-\beta-D-glucopyranosyl ester (gazipashoside A, 1) and 3-O-\beta-D-glucopyranosyl-(1\to 4)-\beta-D-xylopyranosyl- (1\to 3)-\alpha-L-rhamnopyranosyl-(1\to 2)-\alpha-L-arabinopyranosyl hederagenin 28-O-\beta -D-glucopyranosyl-(1\to 6)-\beta-D-glucopyranosyl ester (gazipashoside B, 2), were isolated together with 11 known compounds including 7 triterpene, 1 flavonoid, and 3 iridoidal metabolites from the aerial parts of Cephalaria gazipashensis (Dipsacaceae). The structures of all compounds were elucidated by extensive evaluation of the spectroscopic data (1D- and 2D- NMR, HRESI-MS), as well as chemical examinations. The antimicrobial effects of all pure compounds were tested against gram-positive and gram-negative bacteria. The results indicated that the …


Simultaneous Determination Of Cr(Iii) And Cr(Vi) Using Differential Pulse Polarography And Application To Gerede River, Olcay Şendi̇l, Nabeel Mohammed, Güler Somer Jan 2012

Simultaneous Determination Of Cr(Iii) And Cr(Vi) Using Differential Pulse Polarography And Application To Gerede River, Olcay Şendi̇l, Nabeel Mohammed, Güler Somer

Turkish Journal of Chemistry

Determination of Cr(III) in the presence of Cr(VI) from one polarogram is not easy. No such procedure was found in the literature. In polarographic studies Cr(III) had a peak only in acidic medium, while Cr(VI) had either 1 or 2 peaks in both acidic and basic solutions. In solutions that contain these 2 ions, the peak obtained in acidic medium for Cr(III) will be the sum of both ions. Thus, Cr(III) cannot be determined directly from one polarogram. In this work, a new and simple polarographic method is established for the determination of Cr(III) and Cr(VI) by using only one …


Synthesis And Antimicrobial Evaluation Of Some Annelated Phthalazine Derivatives And Acyclo C-Nucleosides From 1-Chloro-4-(2,4,6-Trimethylphenyl) Phthalazine Precursor, Maher Abdel Aziz El-Hashash, Ahmed Youssef Soliman, Ibrahim Essam Elshamy Jan 2012

Synthesis And Antimicrobial Evaluation Of Some Annelated Phthalazine Derivatives And Acyclo C-Nucleosides From 1-Chloro-4-(2,4,6-Trimethylphenyl) Phthalazine Precursor, Maher Abdel Aziz El-Hashash, Ahmed Youssef Soliman, Ibrahim Essam Elshamy

Turkish Journal of Chemistry

A highly efficient and versatile synthetic approach to the synthesis of annelated phthalazine derivatives viz. 1,2,4-triazolo [3,4-a]phthalazine 11a,b, 14, 18, 19a,b, 29-31, 33, 1,2,4-triazino [3,4-a]phthalazine 25a,b-28, 1,3,5-triazino[4,3-a]phthalazine 22, tetrazolo[5,1-a] phthalazine 23, imidazophthalazine 9a,b,15, and pyrimidinophthlazine 6, 10, 16, 17, 20 is presented. Moreover, acyclo C-nucleoside and double headed acyclo C-nucleoside of 1,2,4-triazolo[3,4-a]phthalazine 12, 13 were obtained via heterocyclization reaction of 1-chloro-4-(2,4,6-trimethylphenyl) phthalazine (4) with gluconic acid hydrazide and galactaric acid bis hydrazide, respectively. The new compounds were synthesized with the objective of studying their antimicrobial activity.