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Full-Text Articles in Chemistry

A New Approach To The Ring Opening Reactions Of 2,7,7-Trimethyl-3,3-Dibromotricyclo[4.1.1.0^{2,4}]Octane, Zeki̇ Şenol, Ömer Zai̇m, Meti̇n Balci Jan 2005

A New Approach To The Ring Opening Reactions Of 2,7,7-Trimethyl-3,3-Dibromotricyclo[4.1.1.0^{2,4}]Octane, Zeki̇ Şenol, Ömer Zai̇m, Meti̇n Balci

Turkish Journal of Chemistry

The reaction of \alpha-pinene and dibromocarbene produced a fairly unstable product, 2,7,7-trimethyl-3,3-dibromotricyclo[4.1.1.0^{2,4}]octane, from which 3-bromo-7,7-dimethyl-2-methylenebicyclo[4,1,1]oct-3-ene and 3-bromo-2,7,7-trimethylbicyclo [4,1,1]octa-2,4-diene were obtained in chloroform at room temperature and in various other media and conditions. Two new compounds, 3-bromo-2,7,7-trimethylbicyclo [4.1.1]oct-3-en-2-ol and 2-(4-bromo-5-methylcyclohepta-3,5-dien-1-yl) propan-2-ol, were observed in aqueous acetone in addition to the previous two. The stability and formation mechanism of the formed products are discussed


Triterpene Saponins From Nigella Sativa L., Mustafa Kemal Taşkin, Özgen Alankuş Çalişkan, Hüseyi̇n Anil, Hassan Abou-Gazar, Ikhlas A. Khan, Erdal Bedi̇r Jan 2005

Triterpene Saponins From Nigella Sativa L., Mustafa Kemal Taşkin, Özgen Alankuş Çalişkan, Hüseyi̇n Anil, Hassan Abou-Gazar, Ikhlas A. Khan, Erdal Bedi̇r

Turkish Journal of Chemistry

Three known triterpene glycosides were isolated from the MeOH extract of dried and powdered seeds of Nigella sativa. The structures of the compounds were established as 3-O-[\beta-D-xylopyranosyl- (1 \to 3)-\alpha-L-rhamnopyranosyl-(1 \to 2)-\alpha -L-arabinopyranosyl]- 28-O-[\alpha-L-rhamnopyranosyl-(1 \to 4)-\beta-D-glucopyranosyl-(1 \to 6)- \beta-D-glucopyranosyl]-hederagenin (1), 3-O-[\alpha -L-rhamnopyranosyl- (1 \to 2)-\alpha-L-arabinopyranosyl]-28-O-[\alpha -L-rhamnopyranosyl-(1 \to 4)- \beta-D-glucopyranosyl-(1\to 6)-\beta-D-glucopyranosyl]-hederagenin (2), and 3-O-[\beta-D-xylopyranosyl- (1\to 3)-\alpha-L-rhamnopyranosyl-(1\to 2)-\alpha- L-arabinopyranosyl]-hederagenin (3) by means of chemical and spectral methods. Compound 2 was isolated for the first time from the genus Nigella.


The Crystal And Molecular Structure Of New Hydrogen Dinitrate Of Nitrato(2,2',2''-Terpyridyl)Platinum(Ii) Ion, [Pt(Terpy)Ono_2][H(Ono_2)_2], Abdurrahman Şengül Jan 2005

The Crystal And Molecular Structure Of New Hydrogen Dinitrate Of Nitrato(2,2',2''-Terpyridyl)Platinum(Ii) Ion, [Pt(Terpy)Ono_2][H(Ono_2)_2], Abdurrahman Şengül

Turkish Journal of Chemistry

The title compound, C_{15}H_{12}N_6O_9Pt, consists of [Pt(terpy)ONO_2]^+ cation and [H(ONO_2)_2]^- anion, in which 2 nitrate groups are linked by a strong hydrogen bond [O \cdots O 2449(1) Å]. In the cation, the terpyridine is coordinated to Pt as a tridentate ligand and the fourth position is occupied by the nitrate ion's oxygen. The coordination around Pt is square-planar. The coordinated nitrate moiety adopts a distorted trigonal-planar configuration. It belongs to the space group P \bar{1} with a = 8.605(2), b = 10.220(3) Å, c = 10.517(2) Å and \alpha = 89.51(1), \beta = 82.78(2), \gamma = 76.90(2)°.


Synthesis, Characterization And Genotoxicity Of Platinum(Ii)Complexes With Subtituted Benzimidazole Ligands, Özteki̇n Algül, Berri̇n Özçeli̇k, Ufuk Abbasoğlu, Fatma Gümüş Jan 2005

Synthesis, Characterization And Genotoxicity Of Platinum(Ii)Complexes With Subtituted Benzimidazole Ligands, Özteki̇n Algül, Berri̇n Özçeli̇k, Ufuk Abbasoğlu, Fatma Gümüş

Turkish Journal of Chemistry

Five Pt(II) complexes with the ligands 2-ethyl-/ or-benzyl-/ or-phenoxymethyl- and 1-methyl-2-hydroxymethyl- and 1-methyl-2-phenyl- benzimidazoles were synthesized and characterized by elemental analysis, and IR and ^1H-NMR spectra and evaluated for their in vitro genotoxic activities by Rec-Assay test. Based on the data obtained in this study, the Pt(II) complexes tested might be taken into consideration as promising antitumor compounds.


An Atropisomeric Chiral 2,2'-Bipyridyl-3,3'-Dicarboxylic Acid And Corresponding Platinum(Ii) Complex, Abdurrahman Şengül Jan 2004

An Atropisomeric Chiral 2,2'-Bipyridyl-3,3'-Dicarboxylic Acid And Corresponding Platinum(Ii) Complex, Abdurrahman Şengül

Turkish Journal of Chemistry

2,2'-Bipyridyl-3,3'-dicarboxylic acid (H_2BDC) spontaneously resolves on crystallization from water, giving monohydrated crystals of the space group P2_12_12_1. In any individual crystal, all the atropisomeric-skewed molecules are of one hand; however, on dissolution in water, optical activity is lost. Strong hydrogen bonding leads to a helical structure, via O--H ... N links, and 3 further strong bonds between water and carboxylate groups produce a framework structure. The pK_a values measured for H_2BDC (3.18 \pm 0.04 and 4.59 \pm 0.02 at 20 \pm 1 °C, in dilute aqueous solution) agree with the zwitterionic form. The reaction of H_2BDC with potassium tetrachloroplatinate(II) in …


Cationic Rearrangements Of An Endo}-Cyclopropyl Methanol System Incorporated In A Benzonorbornadiene System, Abdullah Menzek, Melek Karakaya Jan 2004

Cationic Rearrangements Of An Endo}-Cyclopropyl Methanol System Incorporated In A Benzonorbornadiene System, Abdullah Menzek, Melek Karakaya

Turkish Journal of Chemistry

Chloride 18 (47%) and alcohol 21 (44%) were isolated from the reaction of alcohol 20 with SOCl_2. Cyclopropylcarbinyl -- cyclopropylcarbinyl rearrangement leads to chloride 22, which hydrolyses on separation to give alcohol 21. Chloride 18 results from cyclopropyl -- allylcarbinyl rearrangement, followed by a 1,2 -- aryl shift (sequential rearrangement). Syntheses of compounds 23 and 24 support the structures. The behaviour of 20 differs from that of exo isomer 14, probably due to the nature of the intermediates in these reactions.


Facile Synthesis Of Hydantoin Derivatives Under Microwave Irradiation, Khalil Faghihi, Khosrow Zamani, Akbar Mobinikhaledi Jan 2004

Facile Synthesis Of Hydantoin Derivatives Under Microwave Irradiation, Khalil Faghihi, Khosrow Zamani, Akbar Mobinikhaledi

Turkish Journal of Chemistry

The rapid and highly efficient synthesis of hydantoin derivatives 3(a-f) was achieved under microwave irradiation by using a domestic microwave oven from the reactions of cyanohydrin derivatives 2(a-f) with ammonium carbonate. The reaction proceeded rapidly (2-5 min.), and as a result a series of hydantoin derivatives 3(a-f) were obtained in high yields. All of the synthesized compounds were fully characterized by their melting point, ^1H-NMR, FTIR spectroscopy and elemental analyses. Cyanohydrin derivatives 2(a-f) were also prepared from the ketone derivatives 1(a-f) with potassium cyanide in the presence of sodium metabisulfite in an additional reaction.


Anionic Polymerization Of Methyl Methacrylate As Promoted By A N-Butyl Lithium-Pyridazine-Polyether Alkoxide Based Complex Initiator System, Z. Tim Hamaudi, Ni̇han Nugay, Turgut Nugay Jan 2004

Anionic Polymerization Of Methyl Methacrylate As Promoted By A N-Butyl Lithium-Pyridazine-Polyether Alkoxide Based Complex Initiator System, Z. Tim Hamaudi, Ni̇han Nugay, Turgut Nugay

Turkish Journal of Chemistry

Polymerization of methyl methacrylate was conducted using a n-butyl lithium/pyridazine system as initiator in tetrahydrofuran (THF) and toluene. Special attention was focused on using some lithium polyether alkoxides as polymerization is promoted at ambient temperatures. The positive effects of these \mu /\sigma -type ligands such as lithium 2-(2-methoxyethoxy)ethoxide and lithium 2-(methoxy)ethoxide on controlling the living character, molecular weight, stereoregularity and yield of the produced polymers were all demonstrated. It was found that initiator/lithium-2-(methoxy)ethoxide in a 1/10 ratio gives the most controlled polymerization. All products were then characterized by size exclusion chromatography (SEC), proton nuclear magnetic resonance (^1H NMR) and differential …


Synthesis, Characterization Of Some Co(Iii) Complexes With Vic-Dioxime Ligands And Their Antimicrobial Properties, Erdal Canpolat, Mehmet Kaya, Seher Gür Jan 2004

Synthesis, Characterization Of Some Co(Iii) Complexes With Vic-Dioxime Ligands And Their Antimicrobial Properties, Erdal Canpolat, Mehmet Kaya, Seher Gür

Turkish Journal of Chemistry

In this study, 6 different new vic-dioxime ligands and their mononuclear complexes with Co(III) have been synthesized. The structures of these compounds were identified by using elemental analyses, IR, ^{1}H and ^{13}C NMR, electronic spectra, magnetic susceptibility measurements and conductivity. In addition, the thermal characterizations and antimicrobial activities of the ligands and their complexes have been investigated.


An Efficient Synthesis Of Substituted 4-Aryl-3-Cyano-2-Amino Thiophenes By A Stepwise Gewald Reaction, Ferhan Tümer, Duygu Eki̇nci̇, Kani̇ Zi̇lbeyaz, Ümi̇t Demi̇r Jan 2004

An Efficient Synthesis Of Substituted 4-Aryl-3-Cyano-2-Amino Thiophenes By A Stepwise Gewald Reaction, Ferhan Tümer, Duygu Eki̇nci̇, Kani̇ Zi̇lbeyaz, Ümi̇t Demi̇r

Turkish Journal of Chemistry

The title compounds were efficiently synthesised starting from aryl methyl ketones in 3 steps. Knoevenagel condensation of aryl methyl ketones with malononitrile gave the corresponding crotonitriles (5a-f). Methyl groups of the crotonitriles (5a-f) were then efficiently brominated by refluxing and lightening the reaction media to give bromocrotonitriles (6a-f). The bromocrotonitriles (6a-f) were finally cyclised by treatment with NaSH to give the title compounds.


Synthesis And Reactivity Of Tetrahydroimidazo [1,5-B][1,2,4]Oxadiazol- 2(1h)-Thiones, Necdet Coşkun, Fatma Ti̇rli̇ Tat Jan 2004

Synthesis And Reactivity Of Tetrahydroimidazo [1,5-B][1,2,4]Oxadiazol- 2(1h)-Thiones, Necdet Coşkun, Fatma Ti̇rli̇ Tat

Turkish Journal of Chemistry

1,3-Dipolar cycloaddition of imidazoline 3-oxides 1 with methylisothiocyanate proceeds regio- and diastereoselectively to give tetrahydroimidazo[1,5-b][1,2,4]oxadiazol-2(1H)-thiones 3 in high yields. The cis configuration of the adducts was proved by our double cis elimination test as well as by NOESY experiments. Adducts 3a-c undergo ring opening at reflux in acetonitrile to give imidazoles while 3d-e undergo retro dipolar cycloaddition to give the starting nitrones 1d-e. The imidazooxadiazol-2-thiones 3a-e were treated with concentrated HCl in ethanol at 50 °C to give the corresponding 4H-[1,2,4]oxadiazole-5-thione only in cases in which the substituent at C-6 is an aryl.


Kinetics And Mechanism Of Oxidation Of N--Propanolamine By Dihydroxydiperiodatonickelate(Iv) In Alkaline Medium, Jin-Huan Shan, Jing Qian, Ming-Zhu Gao, Shi-Gang Shen, Han-Wen Sun Jan 2004

Kinetics And Mechanism Of Oxidation Of N--Propanolamine By Dihydroxydiperiodatonickelate(Iv) In Alkaline Medium, Jin-Huan Shan, Jing Qian, Ming-Zhu Gao, Shi-Gang Shen, Han-Wen Sun

Turkish Journal of Chemistry

The kinetics of oxidation of n--Propanolamine (n-PA) by dihydroxy diperiodato-nickelate(IV) (DPN) in alkaline medium was studied with spectrophotometry in a temperature range of 293.2-308.2 K. The reaction was found to be pseudo first-order with respect to DPN and fractional order to n-PA. The rate conatant k_{obs}, rose with an increase in the concentration of OH^{-} and a decrease in the concentration of IO_{4}^{-}. Added salts did not affect the rate and no free radical was detected. From the evaluation of linear data, a reaction mechanism is proposed which involves a pre-equilibrium of an adduct formation between n-PA and dihydroxymonoperiodatonickelate(IV) (MPN), …


Synthesis, Spectral Characterization And Biological Applications Of Tri- And Diorganotin(Iv) Derivatives Of 2-[N-(2,6-Dichloro-3-Methylphenyl)Amino]Benzoic Acid, Sohail Mahmood, Saqib Ali, Moazzam Hussain Bhatti, Mohammad Mazhar, Khadija Shahid, Khalid Mohammed Khan, Ghulam Mustafa Maharvi Jan 2004

Synthesis, Spectral Characterization And Biological Applications Of Tri- And Diorganotin(Iv) Derivatives Of 2-[N-(2,6-Dichloro-3-Methylphenyl)Amino]Benzoic Acid, Sohail Mahmood, Saqib Ali, Moazzam Hussain Bhatti, Mohammad Mazhar, Khadija Shahid, Khalid Mohammed Khan, Ghulam Mustafa Maharvi

Turkish Journal of Chemistry

A series of tri- and diorganotin(IV) compounds with the general formulae R_{3}SnL and R_{2}SnL_{2} (where R = Me, n-Bu, Ph and L = 2-[N-(2,6-dichloro-3-methylphenyl)-amino]benzoate) were synthesized. These compounds were characterized by different instrumental methods such as infrared, multinuclear NMR (^{1}H, ^{13}C, ^{119}Sn) and mass spectrometry. The spectroscopic investigation illustrates that the carboxylate group acts as a bidentate in solid state and as a monodentate in solution. Biological screening tests reveal that the investigated compounds have potential as antibacterial agents.


New Adsorbents From Ti(Opr^{N})_{4} By The Sol-Gel Process: Synthesis, Characterization And Application For Removing Some Heavy Metal Ions From Aqueous Solution, Funda Sayilkan, Hi̇kmet Sayilkan, Sema Erdemoğlu, Şadi̇ye Şener, Murat Akarsu Jan 2004

New Adsorbents From Ti(Opr^{N})_{4} By The Sol-Gel Process: Synthesis, Characterization And Application For Removing Some Heavy Metal Ions From Aqueous Solution, Funda Sayilkan, Hi̇kmet Sayilkan, Sema Erdemoğlu, Şadi̇ye Şener, Murat Akarsu

Turkish Journal of Chemistry

New adsorbents were synthesized by the sol-gel process from the product of a hydrolysis reaction and its coated form of titanium(IV)-n-propoxide for removing some heavy metal ions from aqueous solution. Titanium(IV)-n-propoxide was uncatalyst hydrolyzed with different amounts of water at room temperature and was found to react in a 1:1.6 ratio (mole of Ti:mole of H_{2}O). It was found that the condensation following the hydrolysis reaction was alcohol condensation. The hydrolysis-condensation product was characterized in detail by GC, Karl-Fischer coulometric titrator, NIR-spectroscopy, FT-IR spectroscopy, TG-DTA and elemental analysis. The hydrolysis-condensation product of titanium(IV)-n-propoxide was calcinated at 900 °C after drying …


One Step Synthesis And Some Reactions Of 7-Hydrazino-3,4-Diphenyl- 2h-Pyrazolo [3,4-D] Pyridazine, Ahmet Şener Jan 2004

One Step Synthesis And Some Reactions Of 7-Hydrazino-3,4-Diphenyl- 2h-Pyrazolo [3,4-D] Pyridazine, Ahmet Şener

Turkish Journal of Chemistry

The 7-hydrazino-3,4-diphenyl-2H-pyrazolo-[3,4-d]-pyridazine 3, obtained in 2 different ways consisting of the reactions of anhydrous hydrazine with 4-benzoyl-5-phenyl-2,3-dihydro-2,3-furandione 1 or 3,4-diphenyl-2H-pyrazolo-[3,4-d]-pyridazin-7(6H)-one 2, was converted into hydrazone derivatives 4 by the reactions of 3 with various salicylaldehydes.


Effect Of Radiation On The Persistent Length Of A Chain, B. L. Oksengendler, Ni̇gora Turaeva, I. N. Ruban, S. Sh. Rashidova Jan 2004

Effect Of Radiation On The Persistent Length Of A Chain, B. L. Oksengendler, Ni̇gora Turaeva, I. N. Ruban, S. Sh. Rashidova

Turkish Journal of Chemistry

The effect of radiation on the persistent length of a chain in a water solution of polymer is considered in the work. This effect is suggested to be related to the breaking of the hydrogen bonds in hydrate layers around the chain. The kinetic equation of the breakage of the hydrogen bonds is defined and the stationary solution is found with the help of the equation. The expression of average value of the persistent length of the chain at a fixed average number of broken bonds is determined by means of the Poisson distribution. We found that the persistent length …


^{1}H, ^{13}C, ^{119}Sn Nmr, Mass, Mössbauer And Biological Studies Of Tri-,Di- And Chlorodiorganotin(Iv) Carboxylates, Hajra Masood, Saqib Ali, Mohummad Mazhar, Saira Shahzadi, Khadija Shahid Jan 2004

^{1}H, ^{13}C, ^{119}Sn Nmr, Mass, Mössbauer And Biological Studies Of Tri-,Di- And Chlorodiorganotin(Iv) Carboxylates, Hajra Masood, Saqib Ali, Mohummad Mazhar, Saira Shahzadi, Khadija Shahid

Turkish Journal of Chemistry

The reaction of 2-[(2,3-dimethylphenyl)amino]benzoic acid (HL) with tri- and diorganotin(IV) chlorides yielded complexes of the type R_{3}SnL and R_{2}SnL_{2} (R = n-C_{4}H_{9}, C_{6}H_{5}, C_{6}H_{5}CH_{2}, n-C_{8}H_{17}). The compounds R_{2}SnClL were obtained by a redistribution reaction between R_{2}SnL_{2} and R_{2}SnCl_{2}. All the compounds were characterized by CHN analysis, infrared, multinuclear NMR, mass and Mössbauer spectroscopy. The possible mode of carboxylate group bonding in solid as well as in solution is proposed on the basis of infrared, Mössbauer and NMR (^{1}H, ^{13}C, ^{119}Sn) spectroscopy.


Synthesis And Characterization Of Cu(Ii) Complexes Of Two Ligands Derived From Malonyl Dichloride, Nevi̇n Karaböcek, Serdar Karaböcek, Hasan Mazlum, İsmai̇l Deği̇rmenci̇oğlu, Keri̇m Serbest Jan 2004

Synthesis And Characterization Of Cu(Ii) Complexes Of Two Ligands Derived From Malonyl Dichloride, Nevi̇n Karaböcek, Serdar Karaböcek, Hasan Mazlum, İsmai̇l Deği̇rmenci̇oğlu, Keri̇m Serbest

Turkish Journal of Chemistry

Two different mononucleating ligands incorporating N_{4} and N_{2}S_{2} donor units, 2-(1,3-benzothiazole-2-yl-methyl)-1,3-benzothiazole (L^{1}) and N,N'-bis-(2-amino-phenyl)-malonamide (H_{2}L^{2}) were synthesized by a new method from malonyl dichloride as starting material, and their mononuclear copper(II) complexes were prepared and characterized by elemental analyses, ^{1}H- and ^{13}C-NMR, IR, magnetic moments and mass spectral studies. Elemental analyses, and stochiometric and spectroscopic data of the metal complexes indicate that the metal ions are coordinated to the nitrogen and sulfur atoms and the data support the proposed structure of L^{1}, H_{2}L^{2} and their mononuclear copper(II) complexes. Moreover, the copper(II) complexes of L^{1} and H_{2}L^{2} have a 1:1 metal …


Acylated Iridoid Glycosides From Verbascum Lasianthum, Zeli̇ha Ş. Akdemi̇r, İ. İrem Tatli, Erdal Bedi̇r, Ikhlas A. Khan Jan 2004

Acylated Iridoid Glycosides From Verbascum Lasianthum, Zeli̇ha Ş. Akdemi̇r, İ. İrem Tatli, Erdal Bedi̇r, Ikhlas A. Khan

Turkish Journal of Chemistry

From the roots of Verbascum lasianthum Boiss. ex Bentham 4 catalpol derivatives, 6-O-(\alpha-L-rhamnopyranosyl)-catalpol (1), verbascoside A [= 6-O-(4''-O-trans-p-methoxycinnamoyl)-\alpha -L-rhamnopy- ranosylcatalpol] (2), pulverulentoside I [= 6-O-(3''-O-acetyl-2''-O-trans-p-methoxycinnamoyl)-\alpha -L-rham-nopyranosylcatalpol] (3), and buddlejoside A_{5} [= 6-O-(2''-O-acetyl-3''-O-trans-p-methoxycinnamoyl)-\alpha -L-rhamnopyranosylcatalpol] (4), as well as aucubin (5) and an aucubin derivative, unduloside III [= 6-O-(3''-O-trans-p-methoxycinnamoyl)- \alpha-L-rhamnopyranosylaucubin] (6), were isolated and characterized. The structure elucidation of the compounds was established on the basis of spectroscopic evidence. Buddlejoside A_{5} (4) was found for the first time in the genus Verbascum.


Saponin, Iridoid, Phenylethanoid And Monoterpene Glycosides From Verbascum Pterocalycinum} Var. Mutense, İ. İrem Tatli, Zeli̇ha Ş. Akdemi̇r, Erdal Bedi̇r, Ikhlas A. Khan Jan 2004

Saponin, Iridoid, Phenylethanoid And Monoterpene Glycosides From Verbascum Pterocalycinum} Var. Mutense, İ. İrem Tatli, Zeli̇ha Ş. Akdemi̇r, Erdal Bedi̇r, Ikhlas A. Khan

Turkish Journal of Chemistry

Ilwensisaponin C (= 3-O-{[\alpha-L-rhamnosyl-(1 \to 4)-(\beta-D-glucopyranosyl-(1 \to 3)]-\beta-D-glucopyranosyl]-(1 \to 2)-\beta-fucopyranosyl}-11-methoxy-olean-12-ene-3\beta, 23, 28-triol) (1), ilwensisaponin A (= mimengoside A = 3-O-{[\alpha-L-rhamnosyl-(1 \to 4)-(\beta-D-glucopyranosyl-(1 \to 3)]-\beta -D-glucopyranosyl]-(1 \to 2)-\beta-fucop- yranosyl}-13\beta, 28-epoxyolean-11-ene-3\beta, 23-diol) (2), ajugol (3), picroside IV (= 6^\prime-O-trans- p-hydroxycin- namoylcatalpol) (4), verbascoside {= acteoside, [\beta -(3,4-dihydroxyphenyl)-ethyl]-(3^{\prime-O-\alpha-L-rhamnopyra- nosyl)-(4^{\prime-O-caffeoyl)-\beta-D-glucopyranoside} (5) and 1-(\beta -D-glucopyranosyl)-8-hydroxy-3, 7-dimethyl-oct-2(E), 6(E)- dienoate (6) were isolated from the flowers of Verbascum pterocalycinum var. mutense Hub.-Mor. The structures of the compounds were determined primarily from 1D and 2D NMR experiments. This is the first phytochemical study performed on V. pterocalycinum var. mutense and the first report of the presence of 1-(\beta …


Synthesis Of Some New Pyridylethylated Benzoxa(Thia)Zolinones With Analgesic Activitiy, Nesri̇n Gökhan, Göknur Aktay, Hakki Erdoğan Jan 2004

Synthesis Of Some New Pyridylethylated Benzoxa(Thia)Zolinones With Analgesic Activitiy, Nesri̇n Gökhan, Göknur Aktay, Hakki Erdoğan

Turkish Journal of Chemistry

Eighteen new 3-[2-(2-/4-pyridyl)ethyl]benzoxazolinone (benzothiazolinone) derivatives were synthesized by reacting 2-/4-vinylpyridine and appropriate benzoxazolinones and benzothiazolinones. The analgesic activities of these compounds were investigated by modified Koster and hot-plate tests. Test results revealed that most of the compounds at 100 mg/kg dose levels have higher analgesic activities than acetylsalicylic acid. Compounds with bromo substituents on the phenyl ring in the 6-position of the main ring seemed to show less activity than those with fluorinated ones. Compound 6b showed remarkably high activity in the hot-plate test, although it was inactive in the Koster test. However compound 3a had statistically significant high peripheral …


Synthesis And Some Reactions Of 4-Benzoyl-5-Phenyl-1-(2,4,6-Trichloro Phenyl)-1h-Pyrazole-3-Carboxylic Acid, Ahmet Şener, İshak Bi̇ldi̇ri̇ci̇ Jan 2004

Synthesis And Some Reactions Of 4-Benzoyl-5-Phenyl-1-(2,4,6-Trichloro Phenyl)-1h-Pyrazole-3-Carboxylic Acid, Ahmet Şener, İshak Bi̇ldi̇ri̇ci̇

Turkish Journal of Chemistry

Furandione 1 was reacted with 2,4,6-trichlorophenylhydrazine to give the 1H-pyrazole-3-carboxylic acid 2 together with a new pyridazinone derivative 3. Then 2 was converted into the corresponding ester 5 or amide 6 derivatives, respectively, via reactions of its acid chloride 4 with various alcohols or N-nucleophiles. Nitrile derivative 7 was obtained by dehydration of 6a in a mixture of SOCl_2 and DMF. Condensation reactions of 2 with some hydrazines led to the formation of pyrazolo [3,4-d] pyridazinone 8 derivatives.


Mechanical And Light Transmittance Properties Of Locust Bean Gum Based Edible Films, Meltem Aydinli, Mehmet Tutaş, Ö. Altan Bozdemi̇r Jan 2004

Mechanical And Light Transmittance Properties Of Locust Bean Gum Based Edible Films, Meltem Aydinli, Mehmet Tutaş, Ö. Altan Bozdemi̇r

Turkish Journal of Chemistry

The behavior of locust bean gum (LBG) under heat was investigated by thermogravimetric (TG), differential thermogravimetric (DTG) and differential scanning calorimetric (DSC) methods. It was observed from the TG, DTG and DSC curves that LBG does not melt and is stable up to 300 °C, although exothermic degradation occurs at higher temperatures. The effect of the amount and molecular weight of polyethylene glycol (PEG) on the light transmittance and mechanical properties of these edible films was also examined. Haze increased and the luminous transmittance and total light transmittance values decreased with both the quantity and molecular weight of PEG. On …


The Synthesis Of Substituted 4,4'-Thiobis(Aminophenylglyoxime) And Their Polymeric Metal Complexes With Cu(Ii), Ni(Ii) And Co(Ii) Salts, Ahmet Coşkun, İbrahi̇m Karataş Jan 2004

The Synthesis Of Substituted 4,4'-Thiobis(Aminophenylglyoxime) And Their Polymeric Metal Complexes With Cu(Ii), Ni(Ii) And Co(Ii) Salts, Ahmet Coşkun, İbrahi̇m Karataş

Turkish Journal of Chemistry

4,4'-Bis(chloroacetyl)diphenyl thioether (HL) was synthesized from chloroacetyl chloride and diphenyl thioether in the presence of AlCl_3 as catalyst in a Friedel-Crafts reaction. Subsequently, its keto oxime (H_2L) and glyoxime (H_4L) derivatives were also prepared. Then 3 new substituted 4,4'-thiobis(aminophen- ylglyoxime) (H_4L^{1 - 3}) were synthesized from 4,4'-thiobis(chlorophenylglyoxime) and the corresponding amines. The Ni(II), Cu(II) and Co(II) complexes of these ligands were prepared. The structures of these ligands and their complexes were identifed by FT-IR, ^1H NMR and ICP-AES spectral data, elemental analyses and magnetic measurements.


Determination Of Trace Amounts Of Iodide By An Inhibition Kinetic Spectrophotometric Method, Ramazan Gürkan, Ni̇lgün Bi̇çer, M. Hi̇kmet Özkan, Mehmet Akçay Jan 2004

Determination Of Trace Amounts Of Iodide By An Inhibition Kinetic Spectrophotometric Method, Ramazan Gürkan, Ni̇lgün Bi̇çer, M. Hi̇kmet Özkan, Mehmet Akçay

Turkish Journal of Chemistry

In this study, the reaction between Co(III)-EDTA and hypophosphite ion, catalyzed by Pd(II), was chosen as the indicator reaction. The inhibition kinetics of this catalytic reaction were investigated in the presence of iodide ion and the possibility of its analytical application was evaluated. Catalyzers other than PdCl_2 (Pt, Au and Ni salts) were assayed for the indicator reaction and it was observed that these catalysts have no effect on the reaction. The important variables that affected the reaction rate were investigated and the optimum conditions giving maximum sensitivity were established. The calibration graph, prepared following the inhibition kinetic method, gave …


Sorption Preconcentration And Determination Of Molybdenum(Vi) By Diffuse Reflection Spectroscopy, Olga N. Kononova, Sergey V. Kachin, Anastasiya E. Chaikovskaya, Alexander G. Kholmogorov, Olga P. Kalyaki̇na Jan 2004

Sorption Preconcentration And Determination Of Molybdenum(Vi) By Diffuse Reflection Spectroscopy, Olga N. Kononova, Sergey V. Kachin, Anastasiya E. Chaikovskaya, Alexander G. Kholmogorov, Olga P. Kalyaki̇na

Turkish Journal of Chemistry

The present work focuses on the preconcentration of molybdenum and its determination in aqueous solutions by means of diffuse reflection spectroscopy. The preconcentration of Mo(VI) was carried out using the macroporous strong basic anion exchanger AV-17-10P synthesized on the basis of styrene and divinylbenzene. The method for Mo determination with this collector in industrial solutions and natural water was developed using solid-phase spectroscopy. The colored surface compound to be determined was obtained by a preceding Mo(VI) sorption on the resin and by subsequent treatment of the concentrate obtained with definite amounts of pyrocatechol violet. The calibration curve is linear at …


Determination Of Fluoride In Various Samples And Some Infusions Using A Fluoride Selective Electrode, Şeri̇fe Tokalioğlu, Şenol Kartal, Uğur Şahi̇n Jan 2004

Determination Of Fluoride In Various Samples And Some Infusions Using A Fluoride Selective Electrode, Şeri̇fe Tokalioğlu, Şenol Kartal, Uğur Şahi̇n

Turkish Journal of Chemistry

The determination of fluoride in some environmental samples was performed using a fluoride ion-selective electrode. Fluoride concentrations were determined in drinking waters (from different provinces, districts and villages in Turkey), fruit juices, bottled water samples, toothpastes and tooth powders, liquors of Turkish coffee, coffee, linden, rose hip, and various brand tea infusions, and dust samples collected from the Erciyes University campus car park. The average fluoride concentration in 39 drinking waters was 0.21 mg L^{-1} (0.02--1.42 mg L^{-1}); the level of dissolved fluoride in the dust samples was 1.39 \pm 0.09 \mu g g^{-1}; the fluoride concentrations in liquors taken …


The Effect Of Cultural Conditions On The Variations Of Sod, Cat And Gsh-Px Activities And Lpo Levels In The Filamentous Fungus Fusarium Equiseti, Hülya Ayar Kayali, Leman Tarhan Jan 2004

The Effect Of Cultural Conditions On The Variations Of Sod, Cat And Gsh-Px Activities And Lpo Levels In The Filamentous Fungus Fusarium Equiseti, Hülya Ayar Kayali, Leman Tarhan

Turkish Journal of Chemistry

The changes in the activity of cellular detoxifying defence enzymes such as SOD, CAT and GSH-Px against superoxide anion radical and hydrogen peroxide, and in LPO levels in the filamentous fungus, Fusarium equiseti were measured under growth condition. Experiments were performed comparing changes in glycerol and saccharose (5-25 g/L) as carbon sources, and in glycine, peptone (5-35 g/L) as nitrogen sources in an AFM medium. While SOD activities correlate well with respect to the increase in the glycerol concentration (r = 0.437, p < 0.001), CAT activities showed negative correlation (r = -0.663, p < 0.001). The increase in SOD and CAT activities of F. equiseti correlated with increases in saccharose concentration. When glycerol and saccharose were used as carbon sources, the maximum SOD, CAT and GSH-Px enzymes activities and the minimum LPO level were determined in the medium containing 15 g/L of saccharose on the 12^{th} day at 66.61, 182.79, 1.045 IU/mg and 1.41 nmol MDA/ gr wet weight, respectively. The effects of peptone and glycine as nitrogen sources were also investigated: 53.4% and 48.03% decreases were observed in the SOD and CAT activities of F. equiseti in the presence of 10 g/L of peptone in the culture medium. The presence of 15 g/L of glycine caused 5.30% and 69.90% decreases in the SOD and CAT activities in comparison to the presence of 15 g/L of saccharose, respectively. On the other hand, LPO levels increased in proportion to the decrease in antioxidant enzyme activities in glycine and peptone supplemented media.


3-Hydroxy Fatty Acids From The Flowers Of Hypericum Lysimachioides Var. Lysimachioides, Hasan Çeti̇n Özen, Mehmet Başhan, Zuhal Toker, Cumali̇ Keski̇n Jan 2004

3-Hydroxy Fatty Acids From The Flowers Of Hypericum Lysimachioides Var. Lysimachioides, Hasan Çeti̇n Özen, Mehmet Başhan, Zuhal Toker, Cumali̇ Keski̇n

Turkish Journal of Chemistry

Fatty acid methyl esters in the leaves and flowers of Hypericum lysimachioides var. lysimachioides (Guttiferae) were analyzed by gas chromatography and gas chromatography-mass spectrometry. The flowers of H. lysimachioides var. lysimachioides produced unusual 3-hydroxy fatty acids [3-hydroxy- tetradecanoic acid (3-OH-C14:0) and 3-hydroxy-octadecanoic acid (3-OH-C18:0)], along with other normal fatty acids. Major components were linolenic and palmitic acids for both leaves and flowers.


Flame Atomic Absorption Spectrometric Determination Of Manganese In Alloys After Preconcentration Onto Amberlite Xad-4 Loaded With Saccharomyces Carlsbergensis, Sitki Baytak, A. Rehber Türker Jan 2004

Flame Atomic Absorption Spectrometric Determination Of Manganese In Alloys After Preconcentration Onto Amberlite Xad-4 Loaded With Saccharomyces Carlsbergensis, Sitki Baytak, A. Rehber Türker

Turkish Journal of Chemistry

A sensitive and simple enrichment method using microorganisms as an adsorbent is described for the determination of trace manganese in alloys. Manganese was determined by flame atomic absorption spectrometry after preconcentration onto Amberlite XAD-4 loaded with Saccharomyces carlsbergensis. The optimum values of pH, amount of adsorbent, amount of microorganism, eluent type and volume of sample solution were determined for the quantitative recovery (>95%) of manganese. Results have been compared with those obtained without using microorganisms. Under optimum conditions, recoveries were 98 \pm 3% with microorganisms and 68 \pm 2% without microorganisms for manganese at a 95% confidence level. The …