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Performance Comparison Between Monolithic C18 And Conventional C18 Particle-Packed Columns In The Liquid Chromatographic Determination Of Propranolol Hcl, Sami El Deeb, Hermann Watzig Jan 2006

Performance Comparison Between Monolithic C18 And Conventional C18 Particle-Packed Columns In The Liquid Chromatographic Determination Of Propranolol Hcl, Sami El Deeb, Hermann Watzig

Turkish Journal of Chemistry

Monolithic and conventional particle-packed columns were applied for the determination of propranolol hydrochloride in the presence of its 2 main degradation products, 3-(1-naphthyloxy)-propane-1,2- diol and 4-isopropyl-1,7-bis-(1-naphthyloxy)-4-azaheptane-2,6-diol. The separations were investigated on monolithic columns at flow rates from 1 to 9 mL/min. Fast and efficient separation was obtained by monolithic columns. The analysis time was decreased by about 5-fold on monolithic columns at a flow rate of 4 mL/min, while maintaining sufficient resolution between propranolol and its degradation products. The method was validated using a set of 3 monolithic columns and compared to a conventional (Superspher) C18 column. The precision for …


Synthesis Of Vic-Dioxime Derivatives With Hydrazone Side Groups And Their Metal Complexes, İlknur Babahan, Hüseyi̇n Anil, Nursabah Sarikavakli Jan 2006

Synthesis Of Vic-Dioxime Derivatives With Hydrazone Side Groups And Their Metal Complexes, İlknur Babahan, Hüseyi̇n Anil, Nursabah Sarikavakli

Turkish Journal of Chemistry

Two novel vic-dioxime (L^1H_2, L^2H_2) compounds bearing hydrazone side groups and their transition metal complexes Ni(II), Co(II), Cu(II), and Zn(II) were synthesized. The vic-dioxime ligands bearing hydrazone side groups were synthesized by reacting anti-glyoximehydrazine (GH_2) with 4-nitroacetophenone and 4-methylacetophenenone, respectively. Ligands form mononuclear complexes [(LH)_2M] with a metal to ligand ratio of 1:2 with M=Co(II)(H_2O)_2, Ni(II), and Cu(II). Zn(II) forms complexes [(LH)(H_2O)(Cl)Zn] with a metal to ligand ratio of 1:1. The Co(II) complexes of the ligands are proposed to be octahedral with water molecules as axial ligands, the Ni(II) and Cu(II) complexes are proposed to be square planar, and the …


Synthesis Of Some New Functionalized Octasilsesquioxane Hybrid Nanoclusters. Iii. Potential Of The Octameric Clusters As Hydraulic Lubricating Fluids, Enock O. Dare Jan 2006

Synthesis Of Some New Functionalized Octasilsesquioxane Hybrid Nanoclusters. Iii. Potential Of The Octameric Clusters As Hydraulic Lubricating Fluids, Enock O. Dare

Turkish Journal of Chemistry

The reaction of suitable organic compounds such as \omega -halo-1-alkenes, allyltrichlorosilane or 2-methyl-3-butyn-2-ol in combination with a well-defined inorganic silsesquioxane, H_8Si_8O_{12} A cores, leads to covalently bound organic-inorganic hybrid materials in high yields. The hydraulic fluid properties of these viscous hybrid materials were evaluated and compared with those of some commercially available hydraulic fluids: Mobil EAL 224H, Super-V (AP) and Puroil SHO. The results showed that most silsesquioxane semi-liquids possess hydraulic fluid properties comparable to those of the 3 commercial lubricants.


Synthesis, Crystal Structure And Antifungal/Antibacterial Activity Of Some Novel Highly Functionalized Benzoylaminocarbothioyl Pyrrolidines, H. Ali̇ Döndaş, Yahya Nural, Ni̇zami̇ Duran, Colin Kilner Jan 2006

Synthesis, Crystal Structure And Antifungal/Antibacterial Activity Of Some Novel Highly Functionalized Benzoylaminocarbothioyl Pyrrolidines, H. Ali̇ Döndaş, Yahya Nural, Ni̇zami̇ Duran, Colin Kilner

Turkish Journal of Chemistry

A series of novel highly functionalized benzoylaminocarbothioyl pyrrolidines were prepared from benzoylisothiocyanate and substituted pyrrolidines in excellent yield. The crystal structure of the novel 1-benzoylaminocarbothioyl-5-(naphthyl)- pyrrolidine-2,3,4-tricarboxylicacid trimethyl ester (3a) was determined by X-ray crystal structure analysis. The synthesized compounds were characterized and screened for their in vitro antibacterial and antifungal activities and toxicity. The prepared compounds were tested against the standard strains: Escherichia coli (ATCC 25922), Enterobacter cloacae (ATCC 13047), Enterococcus faecalis (ATCC 29212), Pseudomonas aeruginosa (ATCC 27853), Staphylococcus aureus (ATCC 29213) and Staphylococcus epidermidis (ATCC 12228) and the yeasts Candida albicans (ATCC 90028), Candida krusei (ATCC 6258), Candida parapsilosis …


Superabsorbency, Ph-Sensitivity And Swelling Kinetics Of Partially Hydrolyzed Chitosan-G-Poly(Acrylamide) Hydrogels, Ali Pourjavadi, Gholam Reza Mahdavinia Jan 2006

Superabsorbency, Ph-Sensitivity And Swelling Kinetics Of Partially Hydrolyzed Chitosan-G-Poly(Acrylamide) Hydrogels, Ali Pourjavadi, Gholam Reza Mahdavinia

Turkish Journal of Chemistry

Acrylamide (AAm) monomer was directly grafted onto chitosan using ammonium persulfate (APS) as an initiator and methylenebisacrylamide (MBA) as a crosslinking agent under an inert atmosphere. Two factors affecting the swelling capacity of the obtained hydrogel, AAm and MBA concentrations, were studied. The polymer structures were characterized by FTIR spectroscopy. Water absorbencies of the hydrogels were compared between before and after the alkaline hydrolysis treatment. Saponification of chitosan-g-poly(acrylamide) (chitosan-g-PAAm) with a hot sodium hydroxide solution gave rise to a high water absorbency. Swelling of the hydrogel samples in saline solution (0.15 mol/L NaCl, CaCl_2 and AlCl_3) was examined. Swelling capacity …


Synthesis And Vibrational Spectroscopic Study Of Some Metal(Ii) Halide And Tetracyanonickelate Complexes Of Isonicotinic Acid, Ahmet Ataç, Fehmi̇ Bardak Jan 2006

Synthesis And Vibrational Spectroscopic Study Of Some Metal(Ii) Halide And Tetracyanonickelate Complexes Of Isonicotinic Acid, Ahmet Ataç, Fehmi̇ Bardak

Turkish Journal of Chemistry

The M(IN)_2Ni(CN)_4 [where M: Cu, Mn, Zn, IN: Isonicotinic acid, abbreviated to M-Ni-IN] tetracyanonickelate and some metal halide complexes with the following stoichiometries: Cu(IN)X_2 (X:Br,I), Cd(IN)_2X_2, (X:Cl,Br), and Zn(IN)_4X_2 (X:Br,I) were synthesized for the first time. Their FT-IR spectra were reported in the 4000-400 cm^{-1} region. Vibrational assignments were given for all the observed bands. The analysis of the vibrational spectra indicates that there are some structure-spectrum correlations. For a given series of isomorphous complexes, the sum of the difference between the values of the vibrational modes of uncoordinated isonicotinic acid that were coordinated to the metal ion isonicotinic acid …


Electrochemical Copolymerization Of Thiophene Containing Pseudo-Polyether Cages With Pyrrole, Ati̇lla Ci̇haner, Ahmet M. Önal Jan 2006

Electrochemical Copolymerization Of Thiophene Containing Pseudo-Polyether Cages With Pyrrole, Ati̇lla Ci̇haner, Ahmet M. Önal

Turkish Journal of Chemistry

Conducting copolymers were synthesized via the electrochemical oxidation of pyrrole (Py) in the presence of the monomer 1,12-bis(2-thienyl)-2,5,8,11-tetraoxadodecane (I). The presence of monomer I in the electrolytic solution greatly changed the CV behavior of Py during its potensiodynamic polymerization. The electroactivity of poly(I-co-Py) increased with the increasing amount of I in the comonomer mixture. Copolymer films were prepared via constant potential electrolysis in an electrolytic solution containing 0.1 M tetrabutylammonium hexafluorophosphate (TBAPF_6) dissolved in acetonitrile. The spectroelectrochemical properties of the films were investigated using UV-VIS spectroscopy.


Attempted Synthesis Of 1-Cyclohepta-1,2-Dien-1-Ylbenzene And Wurtz-Like Condensation Products In The Reaction Of 1-(2,3-Dibromocyclohept-1-En-1-Yl)Benzene With Zinc, Mustafa Ceylan, Yakup Budak, M. Burcu Gürdere Jan 2006

Attempted Synthesis Of 1-Cyclohepta-1,2-Dien-1-Ylbenzene And Wurtz-Like Condensation Products In The Reaction Of 1-(2,3-Dibromocyclohept-1-En-1-Yl)Benzene With Zinc, Mustafa Ceylan, Yakup Budak, M. Burcu Gürdere

Turkish Journal of Chemistry

7,7-Dibromo-1-phenylbicyclo[4.1.0]heptane 4 was synthesized and its thermal and silver ion-catalyzed rearrangements were studied. Alcohol 8 was converted to 1-(2,3-dibromocyclohept-1-en-1-yl)benzene 6. The zinc-mediated elimination of 1-(2,3-dibromocyclohept-1-en-1-yl)benzene 6 resulted in the formation of 2 isomeric Wurtz-like condensation products 15 and 16 (whose structural assignments were based on ^1H-and ^{13}C-NMR spectral data) instead of the expected 1-cyclohepta-1,2-dien-1-ylbenzene 14.


A New Flame-Retardant Polyamide Containing Phosphine Oxide And N,N-(4,4-Diphenylether) Moieties In The Main Chain: Synthesis And Characterization, Khalil Faghihi Jan 2006

A New Flame-Retardant Polyamide Containing Phosphine Oxide And N,N-(4,4-Diphenylether) Moieties In The Main Chain: Synthesis And Characterization, Khalil Faghihi

Turkish Journal of Chemistry

A new flame-retardant polyamide containing phosphine oxide moieties in the main chain was synthesized from the solution polycondensation reaction of bis(3-aminophenyl) phenyl phosphine oxide with N,N-(4,4-diphenylether) bis trimellitimide, using thionyl chloride, N-methyl-2-pyrolidone, and pyridine as condensing agents. This new polymer was obtained in high yield (92%), has high inherent viscosity (0.73 dL/g), and was characterized by elemental analysis, FT-IR spectroscopy, thermal gravimetric analysis (TGA and DTG), and solubility testing. Furthermore, another polyamide was prepared by the solution polycondensation reaction of N,N-(4,4-diphenylether) bis trimellitimide with 1,4-phenylene diamine, and its flame-retardant behavior was compared to that of the previous one.


The Impact Of Polyacrylamide Molecular Weight On Its Adsorption Behavior At The Gold/Acidic Solution Interface, Dragica B. Chamovska, Toma P. Grchev, Maja V. Cvetkovska Jan 2006

The Impact Of Polyacrylamide Molecular Weight On Its Adsorption Behavior At The Gold/Acidic Solution Interface, Dragica B. Chamovska, Toma P. Grchev, Maja V. Cvetkovska

Turkish Journal of Chemistry

Adsorption isotherms for polyacrylamide (PAA) on polycrystalline gold, from sulfuric acid (potential range 0-2.0 V/she; 293 K), were obtained by means of cyclic voltammetry with simultaneous monitoring of the double-layer capacity. The Frumkin isotherm indicates that relatively strong attractive forces are present (a = 0.8-1.0), and the Gibbs energies range between 43 and 56 kJ mol^{-1}. The coverage (\theta) of the metal surface with polymer molecules depends on the molar concentration of PAA, as well as on its molecular weight, and the size of the statistical polymer coil in the solution (R_G = 7.49 \times 10^{-3} \times M_n^{0.64}/nm). The adsorption …


The Mechanism And Crystal Structure Of 2-Methoxy-2-Methyl-4-Phenyl-3,4,4a, 10b-Tetrahydro-2h,5h-Pyrano[3,2-C]Chromen-5-One. Acetal Of Warfarin Acid, Saira Shahzadi, Saqib Ali, Irum Asif, Rizwana Ashraf, Guo-Xin Jin Jan 2006

The Mechanism And Crystal Structure Of 2-Methoxy-2-Methyl-4-Phenyl-3,4,4a, 10b-Tetrahydro-2h,5h-Pyrano[3,2-C]Chromen-5-One. Acetal Of Warfarin Acid, Saira Shahzadi, Saqib Ali, Irum Asif, Rizwana Ashraf, Guo-Xin Jin

Turkish Journal of Chemistry

Acetal of warfarin acid has been synthesized via a hemi acetal intermediate and structurally characterized by X-ray diffraction. The crystal structure shows that the title compound was formed by the hydrolysis of warfarin acid in methanol at pH 3, with space group P2_1/n and unit cell parameters a = 5.859 (17), b =16.745 (5), c = 16.402 (5) Å, \alpha = 90.00; \beta = 94.853 (4), and \gamma = 90.00°.


Cerium(Iii) Ion-Selective Electrodes Based On 1,4,7-Trithiacyclononane, Hamid Reza Pouretedal, Abolfazl Semnani, Mohammad Hossein Keshavarz Jan 2006

Cerium(Iii) Ion-Selective Electrodes Based On 1,4,7-Trithiacyclononane, Hamid Reza Pouretedal, Abolfazl Semnani, Mohammad Hossein Keshavarz

Turkish Journal of Chemistry

Novel plasticized polymeric membrane (PPME) and coated platinum wire (CPWE) electrodes based on 1,4,7-trithiacyclononane and oleic acid, as a good lipophilic additive for highly selective determination of Ce^{3+} ions, have been developed. The electrodes exhibit a Nernstian slope of 19.4 mV/decade (for both electrodes) over a wide Ce^{3+} ion concentration range, from 5.0 \times 10^{-6}-5.0 \times 10^{-2} M and 1.0 \times 10^{-7}-1.0 \times 10^{-2} M for PPME and CPWE, respectively. The limits of detection were 3.5 \times 10^{-6} and 8.0 \times 10^{-8} M for PPME and CPWE, respectively. The electrodes possess a fast response time of 15 s, can be …


Synthesis And Properties Of Triazol-5-One Substituted Phthalocyanines By Microwave Irradiation, Bahatti̇n Kahveci̇, Selami̇ Şaşmaz, Musa Özi̇l, Ci̇han Kantar, Başak Koşar, Orhan Büyükgüngör Jan 2006

Synthesis And Properties Of Triazol-5-One Substituted Phthalocyanines By Microwave Irradiation, Bahatti̇n Kahveci̇, Selami̇ Şaşmaz, Musa Özi̇l, Ci̇han Kantar, Başak Koşar, Orhan Büyükgüngör

Turkish Journal of Chemistry

Triazol-5-one substituted phthalocyanines were prepared quickly by the reaction of 4-nitrophthalonitrile with anhydrous metal salts in DBU (1,8-diazabicyclo[5,4,0]undec-7-ene) and DMAE (dimethylaminoethanol) by microwave irradiation. Microwave yields were higher than those of the conventional synthesis methods. All of these complexes are insoluble in polar solvents such as ethanol, ethyl acetate and chloroform. The characterization of the compounds was accomplished by elemental analysis, ^1H NMR (for I and II), ^{13}C NMR (for I and II), IR and UV-Vis spectral data. In addition, the structure of the starting material (I) was determined by single crystal diffraction.


Synthesis, Spectroscopic (Ft-Ir, ^1h, ^{13}C, Mass Spectrometry), And Biological Investigation Of Five-Coordinated Germanium-Substituted Tricyclohexyl Antimony Dipropionates: Crystal Structure Of Tricyclohexylantimony Dibromide, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Kieran C. Molloy, Sarim Dastgir, Farkhanda Shaheen Jan 2006

Synthesis, Spectroscopic (Ft-Ir, ^1h, ^{13}C, Mass Spectrometry), And Biological Investigation Of Five-Coordinated Germanium-Substituted Tricyclohexyl Antimony Dipropionates: Crystal Structure Of Tricyclohexylantimony Dibromide, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Kieran C. Molloy, Sarim Dastgir, Farkhanda Shaheen

Turkish Journal of Chemistry

A series of five-coordinated germanium-substituted tricyclohexylantimony dipropionates have been synthesized and characterized by different instrumental techniques, such as elemental analyses, FT-IR, multinuclear NMR (^1H, ^{13}C) and mass spectrometry. These compounds have also been screened against different microbes and they showed good activity against different bacteria that was comparable to the reference drugs. The crystal structure of the precursor (C_6H_{11})_3SbBr_2 is reported here, which showed that the antimony atom in an asymmetric unit exists in trigonal bipyramidal geometry, having space group C2/c with the monoclinic crystal system.


Synthesis And Anticancer Evaluation Of Some New Unsymmetrical 3,5-Diaryl-4h-1,2,4-Triazole Derivatives, Olcay Beki̇rcan, Bahi̇tti̇n Kahveci̇, Murat Küçük Jan 2006

Synthesis And Anticancer Evaluation Of Some New Unsymmetrical 3,5-Diaryl-4h-1,2,4-Triazole Derivatives, Olcay Beki̇rcan, Bahi̇tti̇n Kahveci̇, Murat Küçük

Turkish Journal of Chemistry

A series of 4-arylidenamino-4H-1,2,4-triazole derivatives (3-11) were synthesized from the treatment of 4-amino-4H-1,2,4-triazoles (2) with certain aldehydes. Compounds 3-11 were reduced with NaBH_4 to afford the corresponding 4-arylmethylenamino-4H-1,2,4-triazoles (12-20). Compounds 1-10 and 12-19 were characterized by elemental analyses and ^1H NMR, ^{13}C NMR, IR and UV spectral data. Compounds 11 and 20 were characterized by ^1H NMR, ^{13}C NMR, IR and mass spectral data. Compounds 14, 16, 17, and 18 were tested for anticancer activities. Compound 17, chosen for its higher anticancer activity in the preliminary tests with the cancer cell lines of MCF7, NCI-H460, and SF-268, exhibited remarkable anticancer …


Synthesis And Characterization Of Metal Complexes Of Cu(Ii), Ni(Ii), Zn(Ii), Co(Ii), Mn(Ii) And Cd(Ii) With Tetradentate Schiff Bases, Jianning Liu, Bo-Wan Wu, Bing Zhang, Yongchun Liu Jan 2006

Synthesis And Characterization Of Metal Complexes Of Cu(Ii), Ni(Ii), Zn(Ii), Co(Ii), Mn(Ii) And Cd(Ii) With Tetradentate Schiff Bases, Jianning Liu, Bo-Wan Wu, Bing Zhang, Yongchun Liu

Turkish Journal of Chemistry

4-(Benzeneazo)salicylaldehyde was synthesized with aniline, sodium nitrite and salicylaldehyde. Two tetradentate ligands, N,N'-bis[4-(benzeneazo) salicylaldehyde]-o-phenylenediamine (H_2L) and N,N'-bis[4-(benzeneazo) salicylaldehyde]ethylenediamine (H_2L') were formed by the 2:1 molar condensation of 4-(benzeneazo) salicylaldehyde with o-phenylenediamine or ethylenediamine. Their Cu(II), Ni(II), Zn(II), Co(II), Mn(II) and Cd(II) complexes were synthesized and characterized by elemental analysis, molar conductivity measurements, and infrared and electronic spectral data. Two ligands and their Ni(II) and Zn(II) complexes were further identified using ^1H NMR spectra. The results suggest that the metal is bonded to the ligand through the phenolic oxygen and the imino nitrogen.


Kinetics And Mechanism Of Oxidation Of 1,3--Butylene Glycol By Dihydroxyditellutoargentate(Iii) In Alkaline Medium, Jin-Huan Shan, Shu-Ying Huo, Shi-Gang Shen, Han-Wen Sun Jan 2006

Kinetics And Mechanism Of Oxidation Of 1,3--Butylene Glycol By Dihydroxyditellutoargentate(Iii) In Alkaline Medium, Jin-Huan Shan, Shu-Ying Huo, Shi-Gang Shen, Han-Wen Sun

Turkish Journal of Chemistry

The kinetics of oxidation of 1,3--butlene glycol (\beta - BG) by dihydroxyditelluto- argentate(III) were studied spectrophotometrically between 298.2 and 313.2 K in alkaline medium. The reaction rate showed pseudo-first order dependence in oxidant and fractional order in \ss-BG. The pseudo-first order rate constant k_{obs} increased with an increase in the concentration of OH^- and a decrease in the concentration of TeO_4^{2-} . There was a negative salt effect and no free radicals were detected. Thus, the dihydroxymonotelluratoargentate(III) species is assumed to be the active species. The activation parameters along with the rate constants of the rate-determining step were calculated.


A Novel Alkaloid From Stapelia Hirsuta, Marwan Shabana, Mariam Gonaid, Maha Mahmoud Salama, Essam Abdel-Sattar Jan 2006

A Novel Alkaloid From Stapelia Hirsuta, Marwan Shabana, Mariam Gonaid, Maha Mahmoud Salama, Essam Abdel-Sattar

Turkish Journal of Chemistry

A novel alkaloid (1,8,8-trimethyl-5,8-dihydro-1H-pyrano[3,4-b]pyridine-4,6-dione) was isolated from the chloroformic traction obtained from the total alcoholic extract of the aerial parts of Stapelia hirsuta L. In addition, apigenin, luteolin and \beta-sitosterol-3-O-\beta-D- glucopyranoside were also isolated.


Synthesis Of A Ruthenium Complex Bound To A Polyimide Matrix: Investigating The Catalytic Properties In A Hydrosilylation Reaction, Turgay Seçki̇n, Süleyman Köytepe, İsmai̇l Özdemi̇r, Beki̇r Çeti̇nkaya Jan 2006

Synthesis Of A Ruthenium Complex Bound To A Polyimide Matrix: Investigating The Catalytic Properties In A Hydrosilylation Reaction, Turgay Seçki̇n, Süleyman Köytepe, İsmai̇l Özdemi̇r, Beki̇r Çeti̇nkaya

Turkish Journal of Chemistry

3,6-Bis(dimethylamino)acridine(hexamethylbenzene)dichlororuthenium(II) was used as a tricyclic heteroatomic monomer to prepare polyimides from the corresponding dianhyrides by solution condensation. The ruthenium complex monomer was synthesized starting from [RuCl_2(HMB)]_2 and 3-6-bis(dimethylamino)acridine. The polymers had inherent viscosities of 1.77 to 2.11 and were soluble in most polar solvents. The glass transition temperatures were in the range of 204 to 298 °C and the 10% weight loss in the range of 506-626 °C, depending upon the structure of the dianhyride monomer. The catalytic activity of the polyimides tested in a hydrosilylation reaction of acetophenone was up to 90%. Leaching of ruthenium into the reaction …


Structure Of 1-(Thiophen-2-Ylmethyl)-2-(Thiophen-2-Yl)-1h-Benzimidazole, Necmi̇ Dege, Memet Şekerci̇, Süleyman Servi̇, Muharrem Di̇nçer, Ünzi̇le Demi̇rbaş Jan 2006

Structure Of 1-(Thiophen-2-Ylmethyl)-2-(Thiophen-2-Yl)-1h-Benzimidazole, Necmi̇ Dege, Memet Şekerci̇, Süleyman Servi̇, Muharrem Di̇nçer, Ünzi̇le Demi̇rbaş

Turkish Journal of Chemistry

The title compound, C_{16}H_{12}N_2S_2, crystallizes in the monoclinic space group P2_1/n with Z = 4, a = 8.950 (5) Å, b = 9.141 (5) Å, c = 17.429 (5) Å and \beta = 93.638 (5)°. The benzimidazole ring is essentially planar. The crystal structure is stabilized by intermolecular C---H ... N and C---H ... \pi contacts.


Studies On 2-Ethyl-3-Carbmethoxy-4-Aryl-5-Oxo-1,4,5,6,7,8-Hexahydroquinoline Derivatives And Calcium Modulatory Activities, Ci̇hat Şafak, Elvan Doğan, Kevser Erol Jan 2006

Studies On 2-Ethyl-3-Carbmethoxy-4-Aryl-5-Oxo-1,4,5,6,7,8-Hexahydroquinoline Derivatives And Calcium Modulatory Activities, Ci̇hat Şafak, Elvan Doğan, Kevser Erol

Turkish Journal of Chemistry

Twelve new compounds having a 2-ethyl-3-carbmethoxy-4-aryl-5-oxo-1,4,5,6,7,8-hexahydroquinoline structure were synthesized, characterized and screened for their calcium modulatory activities. The calcium antagonistic activities of the compounds were investigated by tests performed on isolated rat ileum and lamb carotid artery. Compounds 1, 4, 8 and 9 showed considerable activity.


Heterocyclic Synthesis Using Nitrilimines: Part 5. Synthesis Of Some Novel Spiro Heterocycles, Hany M. Dalloul, Peter H. Boyle Jan 2006

Heterocyclic Synthesis Using Nitrilimines: Part 5. Synthesis Of Some Novel Spiro Heterocycles, Hany M. Dalloul, Peter H. Boyle

Turkish Journal of Chemistry

A new class of spiro-triazoles (4a-m) were synthesized from the reaction of corresponding nitrilimines 2 with substituted heterocyclic benzoylhydrazones 3 in good yields. The spectral data of the new synthesized compounds are in full agreement with their molecular structure.


Synthesis Of New 3-Pyrrolin-2-One Derivatives, Nezi̇re Saygili, Ayşegül Altunbaş, Akgül Yeşi̇lada Jan 2006

Synthesis Of New 3-Pyrrolin-2-One Derivatives, Nezi̇re Saygili, Ayşegül Altunbaş, Akgül Yeşi̇lada

Turkish Journal of Chemistry

Six new 3-pyrrolin-2-one derivatives were synthesized via the condensation reaction of amino acid esters (2a-f) with 2,5-dimethoxy-2,5-dihydrofurane (1) in acidic medium. This simple one-pot reaction furnished the corresponding pyrrolinones (3a-f) in acceptable yields.


Construction Of A Homonaphthazarin Skeleton And Synthesis Of Hydroquinone-Annelated Cycloheptatriene Derivatives, Emi̇n Şengül, Abdullah Menzek, Meti̇n Balci Jan 2006

Construction Of A Homonaphthazarin Skeleton And Synthesis Of Hydroquinone-Annelated Cycloheptatriene Derivatives, Emi̇n Şengül, Abdullah Menzek, Meti̇n Balci

Turkish Journal of Chemistry

1,4-Dihydroxy-7,8-dihydro-5H-benzo[a]cycloheptene-5,9(6H)- dione (7) was synthesised from hydroquinone and glutaric acid chloride via an acylation reaction. The reaction of dione (7) with bromine followed by treatment with NEt_3 gave homonaphthazarin 8 as well as the brominated derivatives 9 and 10. Reduction of 1,4-dimethoxy-7,8-dihydro-5H-benzo[a]cycloheptene-5,9(6H)-dione (16) with LiAlH_4 gave 2 isomeric alcohols, 17 and 18. Reaction of these alcohols with SOCl_2 followed by HCl elimination with NEt_3 afforded dimethoxybenzocycloheptatriene 19 as the sole product. For the synthesis of the isomeric cycloheptatriene 20, the double bond in 19 was isomerised with KOt-Bu.


Synthesis Of N-Alkylnaphthalenes Via Semicarbazones, Gülay Zengi̇n, John W. Huffman Jan 2006

Synthesis Of N-Alkylnaphthalenes Via Semicarbazones, Gülay Zengi̇n, John W. Huffman

Turkish Journal of Chemistry

A number of 1-n-alkylnaphthalenes were prepared via the respective semicarbazones. The semicarbazones were reduced by modified Wolff-Kishner reductions to give 1-n-alkylnaphthalenes in excellent yields as manageable yellow or orange viscous oils. The semicarbazones were prepared from ketones, which are the addition products of Grignard reagents to nitriles. This study offers an excellent preparative method for the synthesis of 1-n-alkylnaphthalenes from semicarbazones, via a 3-step procedure.


Formation Of Yttrium(Iii) Complexes With Salicylic Acid Derivatives In Aqueous Solution, Rahmi̇ye Aydin, Ulvi̇ye Özer Jan 2006

Formation Of Yttrium(Iii) Complexes With Salicylic Acid Derivatives In Aqueous Solution, Rahmi̇ye Aydin, Ulvi̇ye Özer

Turkish Journal of Chemistry

Complexes of yttrium(III) formed with 5-sulphosalicylic acid, 5-SSA (H_3L), and 5-nitrosalicylic acid, 5-NSA (H_2L), were investigated in 0.1 mol.dm^{-3} sodium perchlorate ionic medium at 25.0 \pm 0.1 °C potentiometrically for various molar ratios of Y(III) to these salicylic acid, SA (H_2L), derivatives. Y(III) forms YL and YL_2^{3-} type complexes with 5-SSA that have rather high stabilities (log \beta _1 = 7.91 \pm 0.01 and log \beta _2 = 14.56 \pm 0.06). In the Y(III):5-NSA system, YL^+ and YL_2^- type complexes appear with high stabilities (log \beta _1 = 7.39 \pm 0.02 and log \beta _2 = 13.50 \pm 0.07). Y(III):5-SSA …


Rheology Of Polyaniline Dispersions In Acrylic Resin, Nicoleta Plesu, Smaranda Iliescu, Gheorghe Ilia, Adriana Popa, Cornelia Muntean Jan 2006

Rheology Of Polyaniline Dispersions In Acrylic Resin, Nicoleta Plesu, Smaranda Iliescu, Gheorghe Ilia, Adriana Popa, Cornelia Muntean

Turkish Journal of Chemistry

Acrylic dispersions based on polyaniline were obtained and characterised. The polyaniline was obtained by chemical polymerisation of aniline in different organic acid containing phosphorous, in the presence of ammonium-peroxidisulphate as oxidant agent. The blends were obtained by mechanical dispersion of polyaniline in commercially available acrylic resin. The flow behaviour of these dispersions at different shear rates was studied. Furthermore, the resulting acrylic dispersions were analysed by IR spectroscopy, and were characterised in terms of their electrical resistance and rheological behaviour


Heterogeneous Electron Transfer Rate Constants Of Viologen Monocations At A Platinum Disk Electrode, Naheed Kaukab Bhatti, M. Sadiq Subhani, Ather Yaseen Khan, Rumana Qureshi, Abdur Rahman Jan 2006

Heterogeneous Electron Transfer Rate Constants Of Viologen Monocations At A Platinum Disk Electrode, Naheed Kaukab Bhatti, M. Sadiq Subhani, Ather Yaseen Khan, Rumana Qureshi, Abdur Rahman

Turkish Journal of Chemistry

Experimental values of rate constants for the heterogeneous transfer of electrons to methyl viologen, diquat viologen, benzyl viologen and n-butyl viologen monocations were determined. The process was studied at the surface of a platinum disk in mixtures of water with different aprotic solvents at different temperatures. Theoretical rate constants were evaluated using Marcus' equation, which also contains barrier crossing probability and nuclear frequency. A comparison was made between the theoretical and experimental values of rate constants.


Surface Modification Of Glass Beads With An Aminosilane Monolayer, Gülşi̇n Arslan, Mustafa Özmen, Beni̇z Gündüz, Xunli Zhang, Mustafa Ersöz Jan 2006

Surface Modification Of Glass Beads With An Aminosilane Monolayer, Gülşi̇n Arslan, Mustafa Özmen, Beni̇z Gündüz, Xunli Zhang, Mustafa Ersöz

Turkish Journal of Chemistry

Surface modification of glass beads with a self-assembled monolayer of (3-Aminopropyl)-triethoxysilane (APTES) was investigated. Characterisation of the self-assembled monolayer was confirmed by a reaction between amine terminal groups and thionylchloride of Rhodamine-B dye using fluorescence microscopy. Quantitative 3-dimensional profiling was obtained for all modification processes by converting microscopic images to numerical values. The reaction steps were also analysed using infrared spectroscopy (FTIR).


Optimization Of The Nonaqueous Capillary Electrophoresis Separation Of Metal Ions Using Mixture Design And Response Surface Methods, Cevdet Demi̇r, Yasi̇n Yücel Jan 2006

Optimization Of The Nonaqueous Capillary Electrophoresis Separation Of Metal Ions Using Mixture Design And Response Surface Methods, Cevdet Demi̇r, Yasi̇n Yücel

Turkish Journal of Chemistry

Mixture experimental design was used to enhance the separation selectivity of metal ions in nonaqueous capillary electrophoresis. The separation of cations (Ag, Fe, Cr, Mn, Cd, Co, Pb, Ni, Zn and Cu) was achieved using imidazole as UV co-ion for indirect detection. Acetic acid was chosen as an electrolyte because its cathodic electroosmotic flow permits faster separation. The composition of organic solvents is important to achieve the best separation of all metal ions. Simplex lattice design and response surface methods have proved to be an effective tool to optimize the composition of organic solvents in nonaqueous capillary electrophoresis. Full and …