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2005

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Articles 5041 - 5070 of 5573

Full-Text Articles in Physical Sciences and Mathematics

Kaurane Diterpenoids From Three Sideritis Species, Maurizio Bruno, Franco Piozzi, Nelly Apostolides Arnold, K. Hüsnü Can Başer, Nurhayat Tabanca, Neşe Kirimer Jan 2005

Kaurane Diterpenoids From Three Sideritis Species, Maurizio Bruno, Franco Piozzi, Nelly Apostolides Arnold, K. Hüsnü Can Başer, Nurhayat Tabanca, Neşe Kirimer

Turkish Journal of Chemistry

Some kaurane diterpenoids were isolated from 3 species of the genus Sideritis (Lamiaceae) growing in the Eastern Mediterranean region. Sideritis libanotica subsp. libanotica contained siderol 2 and sideridiol 3. Sideritis erythrantha var. erythrantha yielded sideridiol 3. Sideritis perfoliata gave siderol 2, sideridiol 3 and sideritriol 4. The products are known as they occur in another species of Sideritis growing in Italy and in other species growing also in Turkey. The products are isolated for the first time from these 3 species. The taxonomic significance of these results is discussed.

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Secondary Metabolites Of Phlomis Viscosa And Their Biological Activities, İhsan Çaliş, Hasan Kirmizibekmez, John A. Beutler, Ali̇ Arslan Dönmez, Funda Nuray Yalçin, Ekrem Kiliç, Meral Özalp, Peter Rüedi, Deni̇z Taşdemi̇r Jan 2005

Secondary Metabolites Of Phlomis Viscosa And Their Biological Activities, İhsan Çaliş, Hasan Kirmizibekmez, John A. Beutler, Ali̇ Arslan Dönmez, Funda Nuray Yalçin, Ekrem Kiliç, Meral Özalp, Peter Rüedi, Deni̇z Taşdemi̇r

Turkish Journal of Chemistry

Further phytochemical studies on the aerial parts of Phlomis viscosa (Lamiaceae) led to the isolation of 24 compounds: 3 iridoid glycosides, 10 phenylethanoid glycosides, a megastigmane glycoside and a hydroquinone glycoside, as well as 2 lignan glucosides and 7 neolignan glucosides, 1 of which is new (17b). Compound 17b was obtained as a minor component of an inseparable mixture (2:1) of 2 neolignan glucosides (17a/b), and characterized as 3',4-O-dimethylcedrusin 9-O-\beta -glucopyranoside. Full NMR data of the known 8-O-4' neolignan glucoside, erythro-1-(4-O-\beta-glucopyranosyl-3-methoxyphenyl)- 2-{2-methoxyl-4-[1-(E)-propene-3-ol]-phenoxyl}-propane-1,3-diol (18) are also reported. All isolated compounds were screened for cell growth inhibition versus 3 tumor cell lines …

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The Synthesis And Applications Of Cr-Doped Glymo And Glymo/Damo Surface Coating Systems For Absorbing Uv-Light By Sol-Gel Process, Meltem Asi̇ltürk, Funda Sayilkan, Gali̇p İçduygu, Hi̇kmet Sayilkan Jan 2005

The Synthesis And Applications Of Cr-Doped Glymo And Glymo/Damo Surface Coating Systems For Absorbing Uv-Light By Sol-Gel Process, Meltem Asi̇ltürk, Funda Sayilkan, Gali̇p İçduygu, Hi̇kmet Sayilkan

Turkish Journal of Chemistry

A new glass coating system, containing \gamma- glycidoxypropyltrimethoxysilane/Cr^{3+} (system I:GLYMO/ Cr^{3+}) and \gamma-glycidoxypropyltrimethoxysilane/N-aminoethyl-3- aminopropyltrimethoxysilane/Cr^{3+} (system II:GLYMO/DAMO/Cr^{3+}), was synthesized by the sol-gel technique for UV light absorption applications. UV-visible spectroscopy (UV-VIS) was utilized to investigate the optical properties of coating materials. Especially system II showed very low transmission in the UV wavelength regions (300--400 nm) after thermal treatment of the coated surface. The UV transmission property of surfaces did not change at 80, 100, 450 or 500 °C, but a T value as low as 0.07% was obtained between 150 and 450 °C.

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Cobalt Impregnated Alumina: Nitrogen Adsorption Study At 77 K, Riaz Qadeer, Sumeera Ikram Jan 2005

Cobalt Impregnated Alumina: Nitrogen Adsorption Study At 77 K, Riaz Qadeer, Sumeera Ikram

Turkish Journal of Chemistry

Alumina powder is impregnated with cobalt in the concentration range 5% to 20% (w/v) and is characterized by nitrogen adsorption at 77 K by continuous flow method using the Quantasorb sorption system. It was observed that cobalt metal on impregnation does not contribute any extra surface to alumina. Values of BET surface area determined from nitrogen adsorption data follow the sequence Co (20% w/v) - Al_2O_3 < Co (10% w/v) - Al_2O_3 < Co (5% w/v) - Al_2O_3 < Pure Al_2O_3. Pore size distribution curves demonstrate the mesoporous nature of cobalt impregnated alumina.

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Anhydrous Proton Conductive Polystyrene Sulfonic Acid Membranes, Ayhan Bozkurt Jan 2005

Anhydrous Proton Conductive Polystyrene Sulfonic Acid Membranes, Ayhan Bozkurt

Turkish Journal of Chemistry

A novel anhydrous proton conducting polymer electrolyte based on polystyrene sulfonic acid, PSSA and benzimidazole (BnIm) was synthesized. The PSSA-BnIm interactions were studied by FT-IR. The thermal properties of the blends were investigated by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). The proton conductivities of these materials were measured by AC impedance technique. The conductivities of these materials increase with increasing BnIm content and temperature and maximum conductivity was found to be approximately 5 \times 10^{-4} S/cm at 150 °C.

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Synthesis And Characterization Of New Triheterocyclic Compounds Consisting Of 1,2,4-Triazol-3-One, 1,3,4-Thiadiazole And 1,3,4-Oxadiazole Rings, Nesli̇han Demi̇rbaş Jan 2005

Synthesis And Characterization Of New Triheterocyclic Compounds Consisting Of 1,2,4-Triazol-3-One, 1,3,4-Thiadiazole And 1,3,4-Oxadiazole Rings, Nesli̇han Demi̇rbaş

Turkish Journal of Chemistry

A series of acetic acid derivatives (2a-c) was synthesized by the condensation of compounds 1a-c with chloroacetic acid. The treatment of carboxylic acid derivatives with thiosemicarbazide in phosphorus oxychloride and subsequent diazotation of the products (3a-c) afforded 5-alkyl-2-[(5-chloro-1,3,4-thiadiazol-2-yl)methyl]- 2,4-dihydro-3H-1,2,4-triazol-3-one derivatives (4a-c). The treatment of compounds 4a-c with thiourea produced 5-alkyl-2-[(5-mercapto-1,3,4- thiadiazol-2-yl)methyl]-2,4-dihydro-3H-1,2,4-triazol-3-one derivatives (5a-c). Subsequently, compounds 5a-c were converted to acid hydrazides by treatment with hydrazine hydrate after esterification (7a-e). Moreover, the reaction of compounds 7a-c with carbon disulfite in the presence of KOH afforded 5-alkyl-2-[(5-\{[(5- mercapto-1,3,4-oxadiazol-2-yl)methyl]thio\}-1,3,4-thiadiazol-2-yl)methyl]- 2,4-dihydro-3H-1,2,4-triazol-3-ones (8a-c).

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Color Reaction Of 2-(2-Quinolylazo)-5-Dimethylaminoaniline With Palladium And Its Application, Yunsen Si, Qiufen Hu, Zhangjie Huang, Guangyu Yang, Jiayuan Yin Jan 2005

Color Reaction Of 2-(2-Quinolylazo)-5-Dimethylaminoaniline With Palladium And Its Application, Yunsen Si, Qiufen Hu, Zhangjie Huang, Guangyu Yang, Jiayuan Yin

Turkish Journal of Chemistry

A new chromogenic reagent, 2-(2-quinolylazo)-5-dimethylaminoaniline (QADMAA) was synthesized. A sensitive, selective and rapid method for the determination of palladium based on the rapid reaction of palladium(II) with QADMAA was developed. In the presence of 0.5-2.5 mol L^{-1} of hydrochloric acid solution and cetyl trimethylammonium bromide medium QADMAA reacts with palladium to form a violet complex with a molar ratio of 1:2 (palladium to QADMAA). The molar absorptivity of the chelate is 1.35x10^5 L mol^{-1} cm^{-1} at 600 nm. Beer's law is obeyed in the range of 0.01 to 0.6 \mu g mL^{-1}. The detection limit is 1.2 \mu g L^{-1}. …

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The Atomic Absorption Spectrophotometric Method For Indirect Determination Of Nimodipine In Tablets, Mevlüde Canlica, Sezen İsli̇myeli̇ Jan 2005

The Atomic Absorption Spectrophotometric Method For Indirect Determination Of Nimodipine In Tablets, Mevlüde Canlica, Sezen İsli̇myeli̇

Turkish Journal of Chemistry

A simple indirect atomic absorption spectrophotometric (AAS) method is described for the analysis of nimodipine in tablet formulations. The method is based on the reduction of the antihypertensive drug substances including an aromatic nitro group by boiling them with cadmium metal in 0.05 N HC??l medium under CO_2 atmosphere for 1 h under reflux. The amounts of the drugs were calculated by determining the atomic absorbances of the released Cd^{+2}. The calibration graphs were plotted between the absorbance Cd^{+2} concentrations in the range of 0.242 to 1.209 \mu g.cm^{-3} for nimodipine. As a reference method, the spectrophotometric procedure was developed. …

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Synthesis Of Some New Isoxazolidines By 1,3-Dipolar Cycloaddition Reaction Of Nitrones And Olefins, Akbar Mobinikhaledi, Naser Forughifar, Zahra Kalate Jan 2005

Synthesis Of Some New Isoxazolidines By 1,3-Dipolar Cycloaddition Reaction Of Nitrones And Olefins, Akbar Mobinikhaledi, Naser Forughifar, Zahra Kalate

Turkish Journal of Chemistry

A series of new isoxazolidines 5a-j were synthesized by 1,3-dipolar cycloaddition reaction of different nitrones with substituted olefins under reflux condition. The yields of products following recrystallization from absolute ethanol were of the order of 40%-66%. IR, NMR and mass spectroscopies were used for identification of these compounds.

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Synthesis And Antimicrobial Evaluation Of Some New 2-(2-(P-Chlorophenyl) Benzimidazol-1-Yl Methyl)-5-Substituted Amino-[1,3,4]-Thiadiazoles, Gülgün Ayhan Kilcigi̇l, Canan Kuş, Nurten Altanlar, Süheyla Özbey Jan 2005

Synthesis And Antimicrobial Evaluation Of Some New 2-(2-(P-Chlorophenyl) Benzimidazol-1-Yl Methyl)-5-Substituted Amino-[1,3,4]-Thiadiazoles, Gülgün Ayhan Kilcigi̇l, Canan Kuş, Nurten Altanlar, Süheyla Özbey

Turkish Journal of Chemistry

Some 2-(2-(p-chlorophenyl)benzimidazol-1-ylmethyl)-5-substituted amino-[1,3,4]-thiadiazoles were synthesized and their in vitro antimicrobial activities were tested against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Candida albicans and Candida krusei. Compounds 1b and 12b which possess remarkable activity against C. albicans and marginal activity against C. krusei were found to be the most active compounds in this series. Single crystal X-ray diffraction analysis was performed for compound 8b.

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Flavonol Glycosides From Asperula Arvensis L., Zühal Güvenalp, L. Ömür Demi̇rezer Jan 2005

Flavonol Glycosides From Asperula Arvensis L., Zühal Güvenalp, L. Ömür Demi̇rezer

Turkish Journal of Chemistry

From the aerial parts of Asperula arvensis L. 9 known flavonol glycosides, namely quercetin (1), isoquercitrin [= quercetin 3-O-\beta-glucopyranoside] (2), hyperin [= quercetin 3-O-\beta -galactopyranoside] (3), quercetin 7-O-\beta-galactopyranoside (4), quercetin 4'-O-\beta-galactopyranoside (5), isorhamnetin 3-O-\beta -galactopyranoside (6), isorhamnetin 5-O-\beta-galactopyranoside (7), dihydrokaempferol 7-4'-dimethylether 3-O-\beta -glucopyranoside (8) and isorhamnetin 3-O-\alpha -rhamnopyranosyl (1''' \to 6'')-\beta -glucopyranosid (9), were isolated. The structures of the compounds were elucidated by high field 1D and 2D NMR and ESI-MS spectroscopies.

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Synthesis Of Some Novel Optically Active Isocoumarin And 3,4-Dihydroisocoumarin Containing L-Valine And L-Leucine Moieties, Khosrow Zamani, Khalil Faghihi, Satar Ebrahimi Jan 2005

Synthesis Of Some Novel Optically Active Isocoumarin And 3,4-Dihydroisocoumarin Containing L-Valine And L-Leucine Moieties, Khosrow Zamani, Khalil Faghihi, Satar Ebrahimi

Turkish Journal of Chemistry

Phthalic anhydride was reacted with L-Valine and L-Leucine in a mixture of acetic acid and pyridine at room temperature, and then was refluxed at 90-100 °C and N-phthaloyl-L-valine or N-phthaloyl-L-leucine were obtained in quantitative yields. The imide-acids were converted to N-phthaloyl-L-valine acid chloride and N-phthaloyl-L-leucine acid chloride by reaction with thionyl chloride. Then 2 new derivatives of the chiral isocoumarin with L-valine and L-leucine moieties were synthesised by the condensation reaction of homophthalic acid with respective imide-acid chloride. Furthermore these isocoumarins were converted to 2 new chiral substituted 3,4-dihydroisocoumarins. Biological screening tests reveal that the compounds (3a, 9a) have not …

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Synthesis And Antimicrobial Activities Of Some New Flavonyl Pro-Drug Esters Of Ampicillin, Meltem Ceylan Ünlüsoy, Nurten Altanlar, Rahmi̇ye Ertan Jan 2005

Synthesis And Antimicrobial Activities Of Some New Flavonyl Pro-Drug Esters Of Ampicillin, Meltem Ceylan Ünlüsoy, Nurten Altanlar, Rahmi̇ye Ertan

Turkish Journal of Chemistry

A new series of flavonyl pro-drug esters of ampicillin (Va-b) was prepared by condensing the appropriate bromomethyl flavone with ampicillin trihydrate potassium salt. Flavone derivatives and ampicillin both have good antibacterial activity. The synthesized compounds were tested for their antifungal and antibacterial activities in vitro. Both of the compounds were active against Candida krusei and Staphylococcus aureus.

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Synthesis And Structural Characterization Of The 2-[(O-Pyridyl)-Sulfanylmethyl]-Pyrimidine-Silver(I) Complex [Ag_2(Opsp)_2](No_3)_2, Li-Rong Wen, Ming Li, Gui-Long Zhao, Xue-Mei Li, Ou-Yang Pingkai, Shu-Sheng Zhang Jan 2005

Synthesis And Structural Characterization Of The 2-[(O-Pyridyl)-Sulfanylmethyl]-Pyrimidine-Silver(I) Complex [Ag_2(Opsp)_2](No_3)_2, Li-Rong Wen, Ming Li, Gui-Long Zhao, Xue-Mei Li, Ou-Yang Pingkai, Shu-Sheng Zhang

Turkish Journal of Chemistry

The new silver(I) complexe [Ag_2(opsp)_2](NO_3)_2 (1) was synthesized by the self-assembly of AgX (X = NO_3^-) with the versatile multidentate ligand opsp (opsp = 2-[(o-pyridyl)-sulfanylmethyl]- pyrimidine). X-ray single-crystal diffraction analyses show that 1 is dinuclear molecule. In 1, 1 opsp ligand acts in a bidentate mode with 2 nitrogen atoms from a pyridine ring and a pyrimidine ring coordinating to 2 Ag(I) atoms, and the Ag(I) center is 2-coordinated by 2 nitrogen atoms showing linear coordination geometry.

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A Concise Synthesis And The Antibacterial Activity Of 5,6-Dimethoxynaphthalene-2-Carboxylic Acid, Süleyman Göksu, Meti̇n Tansu Uğuz, Hasan Özdemi̇r, Hasan Seçen Jan 2005

A Concise Synthesis And The Antibacterial Activity Of 5,6-Dimethoxynaphthalene-2-Carboxylic Acid, Süleyman Göksu, Meti̇n Tansu Uğuz, Hasan Özdemi̇r, Hasan Seçen

Turkish Journal of Chemistry

5,6-Dimethoxynaphthalene-2-carboxylic acid was synthesized in 7 steps and with an overall yield of 46%. Bromination of 2-naphthol, and methylation with dimethyl sulfate followed by Friedel-Crafts acylation with AcCl gave 2-acetyl-5-bromo-6-methoxynaphthalene. 2-Acetyl-5-bromo-6-methoxynaphthalene was converted to 5-bromo-6- methoxynaphthalene-2-carboxylic acid by a haloform reaction. The esterification of the acid with methanol, methoxylation with NaOCH_3 in the presence of CuI and subsequent de-esterification with NaOH afforded 5,6-dimethoxynaphthalene-2-carboxylic acid. The 5-bromo-6-methoxynaphthalene-2-carboxylic acid and 5,6-dimethoxynaphthalene-2-carboxylic acid were found to have in vitro antibacterial activity against some pathogenic bacteria.

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Synthesis And In Vitro Antimicrobial And Cytotoxicity Activities Of 2-[(2-Nitro-1-Phenylalkyl)Thio]Benzoic Acid Derivatives, Mehtap Gökçe, Semra Utku, Erdoğan Berçi̇n, Berri̇n Özçeli̇k, Taner Karaoğlu, Ni̇ngur Noyanalpan Jan 2005

Synthesis And In Vitro Antimicrobial And Cytotoxicity Activities Of 2-[(2-Nitro-1-Phenylalkyl)Thio]Benzoic Acid Derivatives, Mehtap Gökçe, Semra Utku, Erdoğan Berçi̇n, Berri̇n Özçeli̇k, Taner Karaoğlu, Ni̇ngur Noyanalpan

Turkish Journal of Chemistry

In this research 14 compounds were tested for their antimicrobial activity. The synthesis of 7 compounds corresponding to 2-[(2-nitro-1-phenyl-propyl)thio]benzoic acids 4 has not been reported before and 7 compounds corresponding to 2-[(2-nitro-1-phenyl-ethyl) thio]benzoic acid 3 were reported by our research group. The antibacterial activity of the title compounds was evaluated by 2 Gram (+) (Staphylococcus aureus, Bacillus subtilis) and 2 Gram (-)(Pseudomonas aeruginosa, Escherichia coli) microorganisms. The antifungal activity of the compounds was also determined against yeast-like fungi (Candida albicans, C. krusei). For antibacterial activity, ampicillin and for antifungal activity, fluconazole and ketoconazole have been used as reference compounds. All …

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The Effect Of Metal Loading On Structural Characteristics And Low Temperature Co Oxidation Activity Of Coprecipitated Co/Al_2o_3, Şeyma Özkara, Ayşe Ni̇lgün Akin, Zülal Misirli, Ahmet Erhan Aksoylu Jan 2005

The Effect Of Metal Loading On Structural Characteristics And Low Temperature Co Oxidation Activity Of Coprecipitated Co/Al_2o_3, Şeyma Özkara, Ayşe Ni̇lgün Akin, Zülal Misirli, Ahmet Erhan Aksoylu

Turkish Journal of Chemistry

The effect of metal loading on structural properties and CO oxidation activity of coprecipitated Co/Al_2O_3 catalysts was investigated. The results indicated the participation of cobalt in the Co-Al skeleton for all coprecipitated samples. Environmental-SEM-EDXS studies showed that at loadings higher than ca. 15 wt.-%, cobalt formed layer-by-layer clusters on the surface; 16.8 wt.-% Co/Al_2O_3 displayed the highest activity and stability in CO oxidation.

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Synthesis And Characterization Of Nitrosyl[Tris(3,5dimethylpyrazolyl)Borato]Molybdenum Complexes Containing Aryloxo, Arylamido And Arylcyano Ligands, Işil Topaloğlu Sözüer, Seçki̇ner Dülger İrdem Jan 2005

Synthesis And Characterization Of Nitrosyl[Tris(3,5dimethylpyrazolyl)Borato]Molybdenum Complexes Containing Aryloxo, Arylamido And Arylcyano Ligands, Işil Topaloğlu Sözüer, Seçki̇ner Dülger İrdem

Turkish Journal of Chemistry

The complexes [MoTp*(NO)X(ZC_6H_4CN-p)] [Tp* = 3,5- dimethylpyrazolyl; X = Cl, Z = O and NH; X = I, Z = CN) were prepared and characterized using ^1H-NMR, IR, FAB mass spectroscopy and micro analysis.

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Synthesis, Characterization And Primary Antimicrobial Activity Evaluation Of 3-Phenyl-6-Methyl-4(3h)-Quinazolinone-2-Yl-Mercaptoacetic Acid Arylidenehydrazides, Aysel Gürsoy, Banu Ünal, Ni̇lgün Karali, Gülten Ötük Jan 2005

Synthesis, Characterization And Primary Antimicrobial Activity Evaluation Of 3-Phenyl-6-Methyl-4(3h)-Quinazolinone-2-Yl-Mercaptoacetic Acid Arylidenehydrazides, Aysel Gürsoy, Banu Ünal, Ni̇lgün Karali, Gülten Ötük

Turkish Journal of Chemistry

3-Phenyl-6-methyl-4(3H)-quinazolinone-2-yl-mercaptoacetic acid hydrazide (3) was reacted with substituted aldehydes in absolute ethanol to obtain a new series, 3-phenyl-6-methyl-4(3H)-quinazolinone- 2-yl-mercaptoacetic acid arylidenehydrazides (4a-q). The structures of 4a-q were elucidated by elemental analyses and from spectrometric (UV, IR, ^1H-NMR, ^{13}C-NMR and EIMS) data. Then 4a-q were evaluated for antibacterial, antifungal and antitubercular activities. No significant activity was observed against the selected microorganisms.

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Synthesis And Isolation Of New Regioisomeric 4-Thiazolidinones And Their Anticonvulsant Activity, Aysel Gürsoy, Nalan Terzi̇oğlu Jan 2005

Synthesis And Isolation Of New Regioisomeric 4-Thiazolidinones And Their Anticonvulsant Activity, Aysel Gürsoy, Nalan Terzi̇oğlu

Turkish Journal of Chemistry

Two regioisomer series, 2-(3-ethyl-4(3H)-quinazolinone-2- ylmercaptoacetylhydrazono)-3-alkyl/3-aryl-5-methyl-4-thiazolidinones (12-21) and 2-arylimino-3-(3-ethyl-4(3H)-quinazolinone-2-ylmercaptoacetylamino)- 5-methyl-4-thiazolidinones (22-26), were synthesized by the cyclization of 1-(3-ethyl-4(3H)-quinazolinone-2-ylmercaptoacetyl)-4-alkyl/aryl thiosemicarbazides (1-11) with ethyl 2-bromopropionate in the presence of anhydrous sodium acetate in anhydrous ethanolic medium. The structures of 12-26 were confirmed by analytical and spectral data (IR, ^1H-NMR and EIMS). Selected members of the thiosemicarbazides and thiazolidinones were subjected to anticonvulsant activity tests by the National Institute of Neurological Disorders and Stroke MD, USA.

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Examination Of Some Organic Explosives By Ion Mobility Spectrometry (Ims), Hülya Koyuncu, Ertan Seven, Ayla Çalimli Jan 2005

Examination Of Some Organic Explosives By Ion Mobility Spectrometry (Ims), Hülya Koyuncu, Ertan Seven, Ayla Çalimli

Turkish Journal of Chemistry

The increase in terrorist activities committed using explosives in recent years has generated the need for improved analytical methods that can accurately and quickly identify explosives and their residues. In this study such an analytical method is evaluated. In the first phase of the study, standard solutions and a standard mixture solution of TNT (2,4,6-trinitrotoluene), RDX (1,3,5-trinitro-1,3,5-triazocyclohexane), PETN (pentaerythritoltetranitrate) and TETRYL (2,4,6-trinitrophenylmethylnitramine) were examined using ion mobility spectrometry (IMS). In the second phase, qualitative analysis of a real explosion residue was carried out and the explosive material used in the bomb was identified by analysing the acetone extract. In the …

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A Novel Method For The Spectrophotometric Determination Of Thallium Using Methiomeprazine Hydrochloride, Hoskere D. Revanasiddappa, Telangusadhushetty N. Kiran Kumar Jan 2005

A Novel Method For The Spectrophotometric Determination Of Thallium Using Methiomeprazine Hydrochloride, Hoskere D. Revanasiddappa, Telangusadhushetty N. Kiran Kumar

Turkish Journal of Chemistry

A new, simple, sensitive, and rapid spectrophotometric method is proposed for the determination of trace amounts of thallium(III). The method is based on the oxidation of methiomeprazine hydrochloride by thallium(III) in phosphoric acid medium to give a blue radical cation, having a maximum absorption at 645 nm. Beer's law is valid over the concentration range 0.5--4.0 \mu g mL^{-1}, with molar absorptivity and Sandell's sensitivity of 3.2 \times 10^4 L mol^{-1} cm^{-1} and 0.0064 \mu g cm^{-2}, respectively. The detection limit of thallium determination is 0.01 \mu g mL^{-1}. The tolerance limits for interfering ions are discussed. All variables were …

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Non-Steroidal Anti-Inflammatory Drugs (Nsaids) As Donor Ligands In Organotin(Iv) Derivatives: Synthesis, Spectroscopic Characterization And Biological Applications, Saira Shahzadi, Khadija Shahid, Saqib Ali, Mohammad Mazhar, Amin Badshah, Ejaz Ahmed, Abdul Malik Jan 2005

Non-Steroidal Anti-Inflammatory Drugs (Nsaids) As Donor Ligands In Organotin(Iv) Derivatives: Synthesis, Spectroscopic Characterization And Biological Applications, Saira Shahzadi, Khadija Shahid, Saqib Ali, Mohammad Mazhar, Amin Badshah, Ejaz Ahmed, Abdul Malik

Turkish Journal of Chemistry

Some new di- and tri-organotin(IV) derivatives of 4 different non-steroidal anti-inflammatory drugs (NSAIDs) with the general formulae R_2SnL_2 and R_3SnL (where R = n-C_{8}H_{17} and C_6H_5CH_2) and L = 2-[(2,3-dimethylphenyl)amino]benzoic acid, 2-(2-fluoro-4-biphenyl)propionic acid, 2-(4-isobutylphenyl) propionic acid and 2-(3-benzoylphenyl)-propionic acid were synthesized. These compounds were structurally characterized by infrared and multinuclear NMR (^1H, ^{13}C, ^{119}Sn) spectroscopies and mass spectrometry. The isotopic effect of tin was studied by comparison of experimental data with the simulated isotopic pattern using the Chemtool software package. These compounds were also screened against different animal and plant pathogens to study their biological activity. LD_{50} data show that …

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Synthesis And Spectral Investigations Of Some Platinum Metals Ions Coordination Compounds Of 4[N-(Furan-2'-Carboxalidene)Amino]Antipyrine Thiosemicarbazone And 4[N-(3',4',5'-Trimethoxybenzalidene)Amino]Antipyrine Thiosemicarbazone, Ram K. Agarwal, Surendra Prasad Jan 2005

Synthesis And Spectral Investigations Of Some Platinum Metals Ions Coordination Compounds Of 4[N-(Furan-2'-Carboxalidene)Amino]Antipyrine Thiosemicarbazone And 4[N-(3',4',5'-Trimethoxybenzalidene)Amino]Antipyrine Thiosemicarbazone, Ram K. Agarwal, Surendra Prasad

Turkish Journal of Chemistry

The present work describes the synthesis and spectral properties of some platinum metals chlorides coordination compounds of 4[N-(-(furan-2'-carboxalidene)amino]antipyrine thiosemicarbazone (FFAAPTS) and 4[N-(3',4',5'-trimethoxybenzalidene)amino]antipyrine thiosemicarbazone (TMBAAPTS). All the compounds have the general composition MCl_2(L) (M = Pd^{2+} or Pt^{2+} ; L = FFAAPTS or TMBAAPTS) or MCl_3(L) (M = Ru^{3+} , Rh^{3+} or Ir^{3+} ; L = FFAAPTS or TMBAAPTS). All the complexes were characterized by elemental analyses, molar conductance, molecular weight, magnetic measurements, and infrared and electronic spectra. The infrared spectra suggest that both the thiosemicarbazones behave as neutral tridentate (N,N,S) ligands. The magnetic and electronic spectra suggest that Pd^{2+} and …

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New Complexes Of Organotin(Iv) 2-(N-Maleoylamino)-2-Methylpropanoate: Synthesis, Spectroscopic Characterization And Biological Activity, Sajjad Ahmad, Saqib Ali, Saira Shahzadi, Fiaz Ahmed, Khalid Mohammed Khan Jan 2005

New Complexes Of Organotin(Iv) 2-(N-Maleoylamino)-2-Methylpropanoate: Synthesis, Spectroscopic Characterization And Biological Activity, Sajjad Ahmad, Saqib Ali, Saira Shahzadi, Fiaz Ahmed, Khalid Mohammed Khan

Turkish Journal of Chemistry

Organotin(IV) complexes of 2-(N-maleoylamino)-2-methylpropanoate were prepared by treating the ligand acid with diorganotin dichloride and triorganotin chloride in 1:2 and 1:1 molar ratios, respectively. These reactions proceeded smoothly to completion and the complexes formed were characterized by elemental analysis, infrared, multinuclear NMR (^1H, ^{13}C, ^{119}Sn) and mass spectrometry. The biological activities of the tin complexes were studied by screening the compounds against various animal and plant pathogens. These results show that triorganotin(IV) carboxylates are more active against the animal and plant pathogens tested as compared to diorganotin dicarboxylates.

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Synthesis, Spectral And Thermal Investigations Of Some Oxovanadium(Iv) Complexes Of Hydrazones Of Isonicotinic Acid Hydrazide, Ram K. Agarwal, Lakshman Singh, Deepak K. Sharma, Ritu Singh Jan 2005

Synthesis, Spectral And Thermal Investigations Of Some Oxovanadium(Iv) Complexes Of Hydrazones Of Isonicotinic Acid Hydrazide, Ram K. Agarwal, Lakshman Singh, Deepak K. Sharma, Ritu Singh

Turkish Journal of Chemistry

A new series of 12 complexes of oxovanadium(IV) with hydrazones of isonicotinic acid hydrazide, namely N-isonicotinamido-3',4',5'-trimethoxybenzalaldimine (INH-TMB) and N-isonicotinamido-2'-furanaldimine (INH-FUR) with the general formula VOX_2.nL (X = Cl, Br, I, NCS, NO_3, n = 1; X = ClO_4, n = 2; L = INH-TMB or INH-FUR) were synthesized and characterized on the basis of analytical, conductance, molecular weight, magnetic moment, infrared and electronic spectral data. The infrared data of the complexes reveal the bidendate nature of both ligands and coordination to carbonyl-oxygen and azomethinic-nitrogen atoms. The probable coordination number of the central metal is 5. Thermal stabilities of the complexes …

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Fast Oxidation Of Lactams To Cyclic Imides Using Microwave Irradiation, Avat Arman Taherpour, Hamid Reza Mansuri Jan 2005

Fast Oxidation Of Lactams To Cyclic Imides Using Microwave Irradiation, Avat Arman Taherpour, Hamid Reza Mansuri

Turkish Journal of Chemistry

Since polar reactants can adsorb microwave irradiation, chemists can utilize the microwave oven for some organic reactions. In this paper, we report a rapid conversion of lactams to cyclic imides using peracetic acid (CH_3-CO_3H) and manganic chloride (MnCl_2) in ethyl acetate (CH_3-COOEt) as a solvent and under microwave irradiation (90 W, 5 min) in good yields.

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Synthesis Of Some New Dihalophenyl- And Dihalobenzylisocoumarins And Their (Dl)-3,4-Dihydroderivatives, Zahid Shafiq, Muhammad Arfan, Nasim Hasan Rama, Shahid Hameed, Ghulam Abbas, Muhammad Tahir Hussain Jan 2005

Synthesis Of Some New Dihalophenyl- And Dihalobenzylisocoumarins And Their (Dl)-3,4-Dihydroderivatives, Zahid Shafiq, Muhammad Arfan, Nasim Hasan Rama, Shahid Hameed, Ghulam Abbas, Muhammad Tahir Hussain

Turkish Journal of Chemistry

3-Dihalophenyl- and dihalobenzylisocoumarins (3a-c) were synthesized by condensation of homophthalic acid (1) with dihalobenzoyl- and dihalophenylacetyl chlorides (2a-c), respectively. The alkaline hydrolysis of these isocoumarins (2a-c) afforded keto-acids (4a-c). (dl)-3-(Dihalophenyl)- and (dl)-3-(dihalobenzyl)- 3,4-dihydroisocoumarins (6a-c) were obtained by reduction of keto-acids (4a-c) to racemic hydroxy-acids (5a-c) followed by cyclodehydration using acetic anhydride.

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Pyranocoumarins From Seseli Gummiferum Subsp. Corymbosum Growing In Turkey, Alev Tosun, Nazi̇re Özkal, Masaki Baba, Toru Okuyama Jan 2005

Pyranocoumarins From Seseli Gummiferum Subsp. Corymbosum Growing In Turkey, Alev Tosun, Nazi̇re Özkal, Masaki Baba, Toru Okuyama

Turkish Journal of Chemistry

Seseli gummiferum Pall. ex Sm. subsp. corymbosum (Boiss. & Heldr.) P.H. Davis (Syn: S. corymbosum Boiss. & Heldr.) (Umbelliferae) collected in southern Anatolia was investigated for the presence of coumarins. A new angular-type pyranocoumarin, corymbocoumarin (1), along with 5 known coumarins (2-6) were isolated from the aerial parts of this plant. Corymbocoumarin (1) was established to be (-)-(3'S,4'S)-3' -acetoxy-4'-isovaleryloxy-3',4' -dihydroseselin (1) and coumarins 2-6 were identified as (-)-(3'S,4'S) -3'-acetoxy-4' -angeloyloxy-3' ,4' -dihydroseselin (2), (+)-(3' S,4' S)-3' -hydroxy-4' -angeloyloxy-3', 4' -dihydroseselin (d-laserpitin) (3), (-)-(3' S,4' S)-3' -angeloyloxy-4' -hydroxy-3', 4' -dihydroseselin (4), 3' -acetoxy-4' -isobutyloxy-3', 4' -dihydroseselin (5) and osthole (6), respectively, …

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Determination Of Cadmium, Copper, Iron, Manganese, Lead And Zinc In Lichens And Botanic Samples By Electrothermal And Flame Atomic Absorption Spectrometry, Orhan Acar, Sümer Özvatan, Murat İli̇m Jan 2005

Determination Of Cadmium, Copper, Iron, Manganese, Lead And Zinc In Lichens And Botanic Samples By Electrothermal And Flame Atomic Absorption Spectrometry, Orhan Acar, Sümer Özvatan, Murat İli̇m

Turkish Journal of Chemistry

Within the framework of the International Atomic Energy Agency (IAEA) Analytical Quality Control Service (AQCS) Chemistry Unit a research program was initiated for the identification of trace elements such as Cd, Cu, Fe, Mn, Pb and Zn in IAEA lichen-338 for a proficiency test (PT). This was to evaluate the possibility of using lichens as biomonitors of trace elements in atmospheric pollution. Pyrolysis and atomization temperatures, atomization and background profiles, detection limits and characteristic masses of analytes in lichen samples with Ni, Ni + Pd and Ni + Pd + tartaric acid (TA) modifier mixture, and without any modifiers were …

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