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One Step Synthesis And Some Reactions Of 7-Hydrazino-3,4-Diphenyl- 2h-Pyrazolo [3,4-D] Pyridazine, Ahmet Şener
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.
Ftir And Ft-Raman Spectral Investigations On 4-Aminoquinaldine And 5-Aminoquinoline, N. Puviarasan, V. Arjunan, S. Mohan
Ftir And Ft-Raman Spectral Investigations On 4-Aminoquinaldine And 5-Aminoquinoline, N. Puviarasan, V. Arjunan, S. Mohan
Turkish Journal of Chemistry
The FTIR spectra of 4-aminoquinaldine and 5-aminoquinoline were recorded in solid phase on a Bruker IFS 66V spectrometer in the region 4000--400 cm^{-1}. The FT-Raman spectra of these compounds were also recorded in the same instrument with a FRA 106 Raman module. The molecules under investigation are considered to have a C_{S} point group by assuming the --NH_{2} and --CH_{3} groups as point masses. All the vibrations are both IR and Raman active. The simple general valance force field (SGVFF) is adopted for both inplane and out of plane vibrations. All the frequencies are assigned in terms of fundamentals, overtones …
Determination Of ^{90}Sr Accumulation In Human Teeth, Recep Acar, Orhan Acar
Determination Of ^{90}Sr Accumulation In Human Teeth, Recep Acar, Orhan Acar
Turkish Journal of Chemistry
The accumulation of ^{90}Sr in decayed or exfoliated human teeth was investigated by ultra low level beta counting. Fuming nitric acid and the necessary carriers and reagents were used for dissolving the samples, and the separation and purification of ^{90}Sr. The Ca contents of samples were determined by flame atomic absorption spectrometry with Zeeman-effect background correction. A mixture of K and La used as a matrix modifier was found to be preferable for the determination of Ca in samples. The optimum concentration and concentration ratio of K and La on the absorbance of Ca in the NIST certified reference material, …
^{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
^{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 Antimicrobial Activity Of Some Pyridyl And Naphthyl Substituted 1,2,4-Triazole And 1,3,4-Thiadiazole Derivatives, Khosrow Zamani, Khalil Faghihi, Taraneh Tofighi, Mohammad Reza Shariatzadeh
Synthesis And Antimicrobial Activity Of Some Pyridyl And Naphthyl Substituted 1,2,4-Triazole And 1,3,4-Thiadiazole Derivatives, Khosrow Zamani, Khalil Faghihi, Taraneh Tofighi, Mohammad Reza Shariatzadeh
Turkish Journal of Chemistry
Synthesis of new 1,2,4-tri and 1,3,4-thiadiazoles, bearing isomeric pyridyl and 1-naphthyl is reported using 1,4-disubstituted thiosemicarbazides in alkaline and acidic media, respectively. The methylthio and benzylthio derivatives of the synthesized triazoles are also reported. All of the synthesized compounds were characterized by their FT-IR, ^{1}H-NMR and mass spectral data. The antibacterial studies of some of the synthesized compounds against S. aureus} and E. coli} as MIC values are reported. None of them have important antibacterial activities.
Acylated Iridoid Glycosides From Verbascum Lasianthum, Zeli̇ha Ş. Akdemi̇r, İ. İrem Tatli, Erdal Bedi̇r, Ikhlas A. Khan
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
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
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 …
Chemical Constituents Of Linaria Aucheri, Di̇lek Erci̇l, M. Koray Sakar, Esther Del Olmo, Arturo San Feliciano
Chemical Constituents Of Linaria Aucheri, Di̇lek Erci̇l, M. Koray Sakar, Esther Del Olmo, Arturo San Feliciano
Turkish Journal of Chemistry
From the petroleum ether and methanol extracts of the aerial parts of Linaria aucheri (Scrophulariaceae) 6 known compounds: \beta-amyrin (1), ergost-7-en-3\beta-ol (2), stigmasta-5,22- E-dien-3\beta -ol (3), stigmast-5-en, 24S-3\beta-ol (4), antirrinoside (5) and linariin (6), were isolated and identified. The structures of these compounds have been elucidated by spectroscopic methods (UV, IR, ^{1}H NMR, ^{13}C NMR, DEPT-135 and GC-MS).
Cationic Rearrangements Of An Endo}-Cyclopropyl Methanol System Incorporated In A Benzonorbornadiene System, Abdullah Menzek, Melek Karakaya
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.
Synthesis And Some Reactions Of 4-Benzoyl-5-Phenyl-1-(2,4,6-Trichloro Phenyl)-1h-Pyrazole-3-Carboxylic Acid, Ahmet Şener, İshak Bi̇ldi̇ri̇ci̇
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.
Chalcogeno Ureas Derived From Bis(1,3-Diazepan-2-Ylidene), Yetki̇n Gök, Engi̇n Çeti̇nkaya
Chalcogeno Ureas Derived From Bis(1,3-Diazepan-2-Ylidene), Yetki̇n Gök, Engi̇n Çeti̇nkaya
Turkish Journal of Chemistry
A series of new electron rich olefins (=\overset{ } CNR(CH_2)_4\overset{ }NR)_2, 3, (a; R = CH_2C_6H_5, b; R = CH_2C_6H_4-OMe-p, c; R = CH_2C_6H_4-NMe_2-p) was generated via the condensation of RNH(CH_2)_4NHR with Me_2NCH (OMe)_2. The C=C bond cleavage reactions of 3 with S_8 and Se provide a simple and straightforward method for the synthesis of 1,3-diazepan-2-chalcogenones 4 and 5, respectively.
Mechanical And Light Transmittance Properties Of Locust Bean Gum Based Edible Films, Meltem Aydinli, Mehmet Tutaş, Ö. Altan Bozdemi̇r
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
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
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
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
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
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
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.
Synthesis, Characterization Of Some Co(Iii) Complexes With Vic-Dioxime Ligands And Their Antimicrobial Properties, Erdal Canpolat, Mehmet Kaya, Seher Gür
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.
Flame Atomic Absorption Spectrometric Determination Of Manganese In Alloys After Preconcentration Onto Amberlite Xad-4 Loaded With Saccharomyces Carlsbergensis, Sitki Baytak, A. Rehber Türker
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 …
Crystal Habit Modification Of Vitamin C (L-Ascorbic Acid) Due To Solvent Effects, Ali̇ Arslantaş, Walter C. Ermler, Rahmi̇ Yazici, Di̇lhan M. Kalyon
Crystal Habit Modification Of Vitamin C (L-Ascorbic Acid) Due To Solvent Effects, Ali̇ Arslantaş, Walter C. Ermler, Rahmi̇ Yazici, Di̇lhan M. Kalyon
Turkish Journal of Chemistry
Crystal morphologies are predicted for vitamin C (L-ascorbic acid) using attachment energy methods. The significant differences between predicted and observed morphologies when vitamin C is grown from water, isopropyl alcohol, acetone-water solution, and isopropyl alcohol-methanol solution are attributed to the effect of solvent on the growth rate of the various crystal habit faces. This effect, particularly the role of hydrogen bonding between solvent and crystal surface, is examined. Molecular modeling is combined with the results of simple experiments charting the habit shift of vitamin C as a function of the hydrogen bonding tendency of the solvent or solvent mixture. Attachment …
Synthesis And Some Reactions Of 4-Benzoyl-5-Phenyl-1-Pyridin-2-Yl-1h- Pyrazole-3-Carboxylic Acid, Ahmet Şener, Esvet Akbaş, M. Kasim Şener
Synthesis And Some Reactions Of 4-Benzoyl-5-Phenyl-1-Pyridin-2-Yl-1h- Pyrazole-3-Carboxylic Acid, Ahmet Şener, Esvet Akbaş, M. Kasim Şener
Turkish Journal of Chemistry
The 1H-pyrazole-3-carboxylic acid 2, obtained from the furandione 1 and 2-hydrazinopyridine, was decarboxylated to give 4-benzoyl-5-phenyl-1-pyridin-2-yl-pyrazole derivative 3. Some ester 4 derivatives of 2 were prepared by the Fischer esterification reactions of 2 with various alcohols. Cyclocondensation reactions of 2 with phenyl hydrazine or hydrazine hydrate led to the formation of derivatives of pyrazolo[3,4-d]pyridazine 5 derivatives.
Determination Of Selenium(Iv) Using O-Phenylenediamine By Differential Pulse Polarography/Interference Of Metal Ions, Recai̇ İnam, Çi̇ğdem Toprak
Determination Of Selenium(Iv) Using O-Phenylenediamine By Differential Pulse Polarography/Interference Of Metal Ions, Recai̇ İnam, Çi̇ğdem Toprak
Turkish Journal of Chemistry
A new sensitive and selective pulse polarographic method for the determination of Se(IV) next to interfering ions is described. This method is based on the highly sensitive peak formed by the reaction of Se(IV) with o-phenylenediamine in Britton-Robinson buffer solution (pH 2.5) at --0.08 V vs. SCE. The new peak due to the Se(IV)/o-PDA complex not only prevents the interference of Pb(II), Cd(II) and Sn(II) for selenium, but also increases its sensitivity. A linear calibration graph is obtained for Se(IV) at a concentration of 5.0 x 10^{-8} to 6.8 x 10^{-5} M with a correlation coefficient of 0.9988. The proposed …
A Convenient Synthesis Of 3,6-Disubstituted-1,4-Dihydro-[1,2,4,5]Tetrazines And Preparation Of New Acetic Acid Derivatives Containing 5-Oxo-4-Phenylamino- 4,5-Dihydro-[1,2,4]Triazole, Ahmet Demi̇rbaş
Turkish Journal of Chemistry
A series of compounds 8a-e, was synthesized by condensation of compounds 7a-e with ethyl bromoacetate. The treatment of compounds 8a-e with hydrazine hydrate afforded the corresponding hydrazide derivatives (9a-e). Subsequently, compounds 9a-e were converted to alkylidene hydrazides (10a-e). Moreover, upon heating in the presence of carboxylic acids, compounds 9a-e unexpectedly gave 1,4-dihydro-[1,2,4,5]tetrazine derivatives (11a-e).
Chemically Crosslinked N-Vinyl-2-Pyrrolidone/2-Hydroxyethyl Methacrylate (Vp/Hema) Copolymer For The Controlled Release Of Cyclic Oligopeptide, Bashir Ahmad, Shumaila Bashir, Shams-Un Nisa, M. B. Huglin
Chemically Crosslinked N-Vinyl-2-Pyrrolidone/2-Hydroxyethyl Methacrylate (Vp/Hema) Copolymer For The Controlled Release Of Cyclic Oligopeptide, Bashir Ahmad, Shumaila Bashir, Shams-Un Nisa, M. B. Huglin
Turkish Journal of Chemistry
Crosslinked copolymers of various compositions of N-vinyl-2-pyrrolidone (VP) and 2-hydroxyethyl methacrylate (HEMA) were prepared chemically in the presence of a crosslinking agent. The swelling mechanism was non-Fickian with about 86% conversion of feed composition to crosslinked copolymer. The reactivity ratios r_1 = 0.045 and r_2 = 3.07 for VP and HEMA indicate that HEMA is more reactive than VP in the reaction. Hydrophilicity, hydrophobicity and monomer composition in the copolymer controlled the drug release from the hydrogels.
A Sensitive Spectrophotometric Assay For Tinidazole And Metronidazole Using A Pd-C And Formic Acid Reduction System, Nandipura Dyavegowda Dinesh, Padmarajaiah Nagaraja, K. Subbegowda Rangappa
A Sensitive Spectrophotometric Assay For Tinidazole And Metronidazole Using A Pd-C And Formic Acid Reduction System, Nandipura Dyavegowda Dinesh, Padmarajaiah Nagaraja, K. Subbegowda Rangappa
Turkish Journal of Chemistry
A simple, sensitive and rapid spectrophotometric method for the determination of tinidazole (TZ) and metronidazole (MZ) in pure as well as in dosage form is described. The method is based on the reduction of the nitro group of drugs using a novel and versatile reduction system comprising 10% Pd-C and formic acid. The resulting amine was then subjected to a condensation reaction with sodium 1,2-naphthaquinone-4-sulfonate (NQS) to form red Schiff base with an absorption maximum at 510 nm. Beer's law was obeyed in the concentration ranges 2.0 to 45.0 \mu g mL^{-1} and 1.5 to 37.0 \mu g mL^{-1} with …
Facile Synthesis Of Hydantoin Derivatives Under Microwave Irradiation, Khalil Faghihi, Khosrow Zamani, Akbar Mobinikhaledi
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.
The Kinetics Of The Photochemical Reaction Of Methylene Green With Methylamine And Ethylamine, Rehana Saeed, Fahim Uddin, Zahida Khalid
The Kinetics Of The Photochemical Reaction Of Methylene Green With Methylamine And Ethylamine, Rehana Saeed, Fahim Uddin, Zahida Khalid
Turkish Journal of Chemistry
The photochemical reduction of methylene green with methylamine and ethylamine in 50% aqueous isopropanol was studied. The photochemical reduction was carried out in a special type of optical processor associated with a deoxygenating system, a temperature controlling unit and a magnetic stirring system. A monochromatic light of 657 nm wavelength was used for irradiation of oxygen free reaction solutions in a double walled reaction cell. The transmitted light was measured and recorded in terms of electrical signals with the help of a calibrated galvanometer. Acidities of the solutions were measured with the help of a spectrophotometer based on the Hammet …