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- 3-dioxin-4-one (1)
- 3-diphenylphenyl phosphine oxide) bistrimellitimide diacid chloride (1)
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- 3-oxopropanenitrile (1)
- 4' -diazaflavone (1)
- 4' -diazaflavonium bromide (1)
Articles 1 - 30 of 74
Full-Text Articles in Physical Sciences and Mathematics
Electrocatalytic Oxidation Of D-Glucose Using A Cd Ad-Atom-Modified Au(111) Electrode In Alkaline Solution, Zekerya Dursun, Sami Ben Aoun, Isao Taniguchi
Electrocatalytic Oxidation Of D-Glucose Using A Cd Ad-Atom-Modified Au(111) Electrode In Alkaline Solution, Zekerya Dursun, Sami Ben Aoun, Isao Taniguchi
Turkish Journal of Chemistry
Au(111) single crystal electrodes were modified by underpotential deposition (UPD) of Cd ad-atoms with different coverages, which were used for the electrocatalytic oxidation of glucose in alkaline media. The catalytic activity of the electrodes was dependent on how the Cd ad-atoms covered the surface. Under the presented experimental conditions the monolayer (ML) Cd ad-atom-covered Au(111) electrode had the best catalytic activity on D-glucose oxidation, in terms of both potential shifts and peak current increases, as compared to the 0.11, 0.5, and 2 ML covered and bare Au(111) electrodes. Double layer capacity measurements revealed that the shifts of the potential of …
Synthesis And Antimicrobial Evaluation Of Novel Di-Triazoles And 4-Arylidene Amino 4,5 Dihydro-1h-[1,2,4] Triazole-5-One Derivatives, Yasemi̇n Ünver, Esra Düğdü, Kemal Sancak, Mustafa Er, Şengül Alpay Karaoğlu
Synthesis And Antimicrobial Evaluation Of Novel Di-Triazoles And 4-Arylidene Amino 4,5 Dihydro-1h-[1,2,4] Triazole-5-One Derivatives, Yasemi̇n Ünver, Esra Düğdü, Kemal Sancak, Mustafa Er, Şengül Alpay Karaoğlu
Turkish Journal of Chemistry
A series of novel di-[3(thiophen-2-yl-methyl)-4,5-dihydro-1H- [1,2,4]triazole-5-one-4yl]n-alkanes (2a-h) were obtained by the reaction of N'-1-ethoxy-2-thiophen-2-yl-ethylydene hydrazino carboxylic acid ethyl ester (1) and diamines. Compound 3 was reacted with aldehydes and 4-(arylidene-amino)-3-thiophen-2-yl-methyl-4,5-dihydro-1H-[1,2,4] triazole-5-ones (4, 5, and 8) with Schiff base character were synthesized. (4-(arylidene-amino)-5-oxo-3-thiophen-2-yl-methyl-4,5- dihydro-1H-[1,2,4]triazole-1-yl)-acetic acid ethyl esters (6, 7, and 9) were obtained by the reaction of 4-(arylidene-amino)-3-thiophen-2-yl- methyl-4,5-dihydro-1H-[1,2,4]triazole-5-ones (4, 5, and 8) and ethyl bromoacetate. The structures of the new compounds were inferred through IR, ^1H/^{13}C NMR, elemental analyses, and mass spectral data. Compound 8i was characterized by IR, ^1H/^{13}C NMR, elemental analyses, mass, and X-ray spectral techniques. Geometry optimization …
The Crystal Structure Of 2-Nitro-N-(4-Nitrophenyl)Benzamide, Aamer Saeed, Shahid Hussain, Ulrich Flörke
The Crystal Structure Of 2-Nitro-N-(4-Nitrophenyl)Benzamide, Aamer Saeed, Shahid Hussain, Ulrich Flörke
Turkish Journal of Chemistry
2-Nitro-N-(4-nitrophenyl)benzamide was synthesized and characterized by spectroscopy and elemental analysis. The crystal structure was determined from single-crystal X-ray diffraction data. It crystallizes in the orthorhombic space group, P 2_12_12_1, with unit cell dimensions a = 8.9443(10) Å, b = 9.7147(11) Å, and c = 13.8016(16) Å. The dihedral angle between the 2 aromatic rings is 82.32(4)^{\circ}. The N2 and N3 nitro groups are oriented with respect to their attached phenyl rings at dihedral angles of 1.97(3)^{\circ} and 15.73(3)^{\circ}, respectively. The intramolecular C-H{\ldots}O hydrogen bond results in the formation of a non-planar 6-membered ring. In the crystal structure, intermolecular N-H...O hydrogen …
Biologically Active Transition Metal Chelates With A 2-Thiophenecarboxaldehyde-Derived Schiff Base: Synthesis, Characterization, And Antibacterial Properties, Cezar Spinu, Maria Pleniceanu, Cristian Tigae
Biologically Active Transition Metal Chelates With A 2-Thiophenecarboxaldehyde-Derived Schiff Base: Synthesis, Characterization, And Antibacterial Properties, Cezar Spinu, Maria Pleniceanu, Cristian Tigae
Turkish Journal of Chemistry
Metal complexes, ML_2Cl_2, where M is Fe(II), Co(II), Ni(II), Cu(II), Zn(II), or Cd(II), and L is the Schiff base formed by condensation of 2-thiophenecarboxaldehyde with 2-aminopyridine, N-(2-thienylmethylidene)-2-aminopyridine (TNAPY) have been prepared and characterized by elemental analysis, and magnetic and spectroscopic measurements. Elemental analysis of the chelates suggests the stoichiometry is 1:2 (metal-ligand). Infrared and NMR spectra of the complexes agree with the coordination to the central metal atom through the nitrogen of the azomethine (-HC=N-) group and the sulfur atom of the thiophene ring. Magnetic susceptibility data coupled with electronic and ESR spectra suggest a distorted octahedral structure for the …
Determination Of Iridoid Glycosides From Four Turkish Lamium Species By Hplc-Esi/Ms, Funda Nuray Yalçin, Duygu Kaya, İhsan Çaliş, Tayfun Ersöz, Erhan Palaska
Determination Of Iridoid Glycosides From Four Turkish Lamium Species By Hplc-Esi/Ms, Funda Nuray Yalçin, Duygu Kaya, İhsan Çaliş, Tayfun Ersöz, Erhan Palaska
Turkish Journal of Chemistry
An HPLC-ESI/MS method that enables fast detection and identification of iridoid glycosides is described. Eleven iridoid glycosides known to occur in the genus Lamium-lamalbide, sesamoside, 6-\beta-OH ipolamiide, shanzhiside methyl ester, dehydropenstemoside, barlerin (= 8-O-acetylshanzhiside methyl ester), 6-O-syringyl-8-O- acetylshanzhiside methyl ester, lamerioside, lamiide, eriobioside, and ipolamiide, were identified by means of their retention time and ESI/MS data. This method was successfully applied to the identification of the iridoid composition of the n-butanol extracts of Lamium eriocephalum Bentham subsp. eriocephalum, L. garganicum L. subsp. pulchrum R. Mill, L. garganicum L. subsp. laevigatum Arcangeli, and L. purpureum L. var. purpureum from the Turkish …
The Kinetics And Mechanism Of Ruthenium(Iii)-Catalyzed Oxidation Of Tris(2-Amino Ethyl)Amine By Hexacyanoferrate(Iii) In Aqueous Alkaline Medium, Radhey Mohan Naik, Abhishek Srivastava, Amit Kumar Verma
The Kinetics And Mechanism Of Ruthenium(Iii)-Catalyzed Oxidation Of Tris(2-Amino Ethyl)Amine By Hexacyanoferrate(Iii) In Aqueous Alkaline Medium, Radhey Mohan Naik, Abhishek Srivastava, Amit Kumar Verma
Turkish Journal of Chemistry
The kinetics of ruthenium(III)-catalyzed oxidation of TREN, i.e. tris(2-amino ethyl)amine(3-hydrochloride) by an outer sphere electron transfer oxidant, potassium hexacyanoferrate(III), was investigated spectrophotometrically in aqueous alkaline medium. The extent of the reaction was followed by registering a decrease in absorbance at 420 nm (\lambda_{max} of Fe(CN)_6^{3-}) due to its consumption as a function of [OH^-], ionic strength, [Fe(CN)_6^{3-}], [TREN], and temperature by varying only one variable at a time and keeping all other variables constant. The rate data indicate that the reaction exhibited first order dependence in [oxidant] and at a lower concentrations of reductant. The overall reaction follows second order …
Interaction Of Mefenamic Acid With Cobalt(Ii) Ions In Aqueous Media: Evaluation Via Classic And Response Surface Methods, Mohammad Edrissi, Nima Razzaghi Asl, Behrooz Madjidi
Interaction Of Mefenamic Acid With Cobalt(Ii) Ions In Aqueous Media: Evaluation Via Classic And Response Surface Methods, Mohammad Edrissi, Nima Razzaghi Asl, Behrooz Madjidi
Turkish Journal of Chemistry
Mefenamic acid reacts with cobalt(II) ions in aqueous alkaline medium to form a highly stable deep brown complex at ambient temperature. The complexation process was optimized in terms of pH, temperature, agitation rate, and contact time using classical studies. A response surface method based on Box-Behnken design was used to statistically model the complexation reaction and investigate factor effects along with their interactions. A quadratic model was developed using experimental data with a correlation coefficient of 0.9609. Numerical optimization was performed to achieve the optimum solutions of factor combinations. The results of the classical investigation and statistical method were in …
Novel Analogues Of 2-Pyrazoline: Synthesis, Characterization, And Antimycobacterial Evaluation, Ahmet Özdemi̇r, Gülhan Turan Zitouni, Zafer Asim Kaplancikli
Novel Analogues Of 2-Pyrazoline: Synthesis, Characterization, And Antimycobacterial Evaluation, Ahmet Özdemi̇r, Gülhan Turan Zitouni, Zafer Asim Kaplancikli
Turkish Journal of Chemistry
Fourteen new 1-[(N,N-disubstitutedthiocarbamoylthio)acetyl]- 3-(2-thienyl)-5-aryl-2-pyrazoline derivatives were synthesized by reacting 1-(chloroacetyl)-3-(2-thienyl)-5-aryl-2-pyrazolines and appropriate sodium salts of N,N-disubstituted dithiocarbamoic acids in acetone. The structures of the synthesized compounds were confirmed by UV, IR, ^1H-NMR, and FAB^+-MS spectral data. The compounds were evaluated for in vitro antimycobacterial activity against Mycobacterium tuberculosis H37Rv using the BACTEC 460 radiometric system and BACTEC 12B medium. The preliminary results showed that all of the tested compounds were inactive against the test organism.
Preparation And Potentiometric Study Of Promethazine Hydrochloride Selective Electrodes And Their Use In Determining Some Drugs, Nabil S. Nassory, Shahbaz A. Maki, Bashaer A. Al-Phalahy
Preparation And Potentiometric Study Of Promethazine Hydrochloride Selective Electrodes And Their Use In Determining Some Drugs, Nabil S. Nassory, Shahbaz A. Maki, Bashaer A. Al-Phalahy
Turkish Journal of Chemistry
Promethazine hydrochloride selective electrodes were constructed based on promethazine-phosphotun- gstic acid ion pair in PVC matrix membrane. The plasticizers used were di-butyl phosphate (DBP), tri-n-butyl phosphate (TBP), o-nitro phenyl octyl ether (ONPOE), and di-n-butyl phthalate (DBPH). The electrodes based on DBP, TBP, and ONPOE gave the same linear range between 1 x 10^{-4} and 1 x 10^{-1} M, while the one based on DBPH ranged between 5 x 10^{-4} and 1 x 10^{-1}M. The slopes for linear range ranged from 40 to 56 mV/decade with correlation coefficients lying between 0.9984 and 0.9993. The best detection limit was 2 x 10^{-5}M …
Potentiometric Utility Of The New Solid-State Sensor Based On Crowned Ionophore For The Determination Of K^+, Bariş Kemer, Mustafa Özdemi̇r
Potentiometric Utility Of The New Solid-State Sensor Based On Crowned Ionophore For The Determination Of K^+, Bariş Kemer, Mustafa Özdemi̇r
Turkish Journal of Chemistry
All solid-state contact poly vinyl chloride (PVC) membrane potassium-selective electrode has been developed. The construction of the ion selective electrode membrane was organized using ionophore 4,4'-bis[4''-phenoxy(15-crown-5) methyl]benzyl in PVC cocktail. The potentiometric performance characteristics of the electrode were investigated by a computerized system. The electrode was found highly selective to K^+ ions over a wide variety of other cations. The electrode almost exhibited a Nernstian response (\ge 55 (\pm15) mV/decade of K activity) to K^+ within the concentration range 1.5 x 10^{-1} - 1.0 \times 10^{-5} M. The operational pH range of the electrode was 5--7. The response time of …
Langmuir Aggregation Of Congo Red On Cpc And Its Application, Xiang-Hu Liu, Jiao-Rong Ren, Ya-Nan Huang, Jing Bai, Hong-Wen Gao
Langmuir Aggregation Of Congo Red On Cpc And Its Application, Xiang-Hu Liu, Jiao-Rong Ren, Ya-Nan Huang, Jing Bai, Hong-Wen Gao
Turkish Journal of Chemistry
In this paper, microsurface adsorption-spectral correction technique (MASCT) was used to research the interaction between negatively charged sodium diphenyl diazo-bis-\alpha -naphthylamine-4-sulfonate (Congo Red, CR) and positively charged cetylpyridinium chloride (CPC) in a pH 2.03 BR buffer solution. The experiment results indicate that CR was absorbed on the surface of CPC mainly through electrostatic attraction. This aggregation obeys the Langmuir isothermal adsorption equation. The maximal binding number of CR to CPC was calculated to be 1.2 and the adsorption constant was about 2.03 \times 10^5 L/mol. This CR-CPC binding product is insensitive to a concentrated electrolyte solution, but higher temperature influences …
Electrocatalytic Oxidation Of Hydroxylamine At A Quinizarine Modified Glassy Carbon Electrode: Application To Differential Pulse Voltammetry Detection Of Hydroxylamine, Mohammad Mazloumardakani, Payam Ebrahimi Karami, Hossein Naeimi, Bibifatemeh Mirjalili
Electrocatalytic Oxidation Of Hydroxylamine At A Quinizarine Modified Glassy Carbon Electrode: Application To Differential Pulse Voltammetry Detection Of Hydroxylamine, Mohammad Mazloumardakani, Payam Ebrahimi Karami, Hossein Naeimi, Bibifatemeh Mirjalili
Turkish Journal of Chemistry
The electrocatalytic behavior of hydroxylamine was studied on a glassy carbon electrode modified by electrodeposition of quinizarine, using cyclic voltammetry, chronoamperometry, and rotating disk voltammetry as diagnostic techniques. Cyclic voltammetry showed that the catalytic current of the system depends on the concentration of hydroxylamine. The magnitude of the peak current for quinizarine increased sharply in the presence of hydroxylamine and proportional to hydroxylamine concentration. The diffusion coefficient of hydroxylamine and the catalytic rate constant for the catalytic reaction of quinizarine with hydroxylamine were also estimated using a rotating disk electrode experiment. The kinetics parameters of this process were calculated, and …
Synthesis And Antifungal Activity Of Some Novel N-(4-Phenyl-3-Aroylthiazol-2(3h)-Ylidene) Substituted Benzamides, Aamer Saeed, Sabah Zaman, Maryam Jamil, Bushra Mirza
Synthesis And Antifungal Activity Of Some Novel N-(4-Phenyl-3-Aroylthiazol-2(3h)-Ylidene) Substituted Benzamides, Aamer Saeed, Sabah Zaman, Maryam Jamil, Bushra Mirza
Turkish Journal of Chemistry
Variously substituted N-(4-phenyl-3-aroylthiazol-2(3H)-ylidene)benzamides (2a-t) were prepared by base-catalyzed cyclization of corresponding 1-aroyl-3-aryl thioureas with acetophenone in the presence of bromine. Some of the synthesized compounds were assayed in vitro for their antifungal activity and were found to exhibit low to moderate activity.
Thermal Decomposition Of Metal Complexes Of Type Mlx_2 (M = Co(Ii), Cu(Ii), Zn(Ii), And Cd(Ii); L = Die; X = No_3^{1-}) By Tg-Dta-Dtg Techniques In Air Atmosphere, Muhammad Arshad, Saeed Ur-Rehman, Ammad Hussain Qureshi, Khalid Masud, Muhammad Arif, Aamer Saeed, Riaz Ahmed
Thermal Decomposition Of Metal Complexes Of Type Mlx_2 (M = Co(Ii), Cu(Ii), Zn(Ii), And Cd(Ii); L = Die; X = No_3^{1-}) By Tg-Dta-Dtg Techniques In Air Atmosphere, Muhammad Arshad, Saeed Ur-Rehman, Ammad Hussain Qureshi, Khalid Masud, Muhammad Arif, Aamer Saeed, Riaz Ahmed
Turkish Journal of Chemistry
The nitrate complexes of transition metals with 1,2-diimidazoloethane (DIE) of the general formula M(DIE)(NO_3)_2, where M = Co(II), Cu(II), Zn(II), and Cd(II), were synthesized. The compositions of metal complexes and ligand were investigated by elemental analysis in order to ensure their purity and the structure elucidations were based on conductivity measurements, room temperature magnetic moment studies, proton NMR, and electronic and IR spectra. The thermal behavior of these complexes possessing distorted tetrahedral geometry and their ligand was studied by means of thermoanalytical techniques in static air atmosphere in order to determine their mode of decomposition and thermal stability. All these …
The Synthesis And Antimicrobial Activity Of \\\\Gamma-Butyrolactone Derivatives, Slobodan Sukdolak, Slavica Solujic-Sukdolak, Nenad Vukovic, Tanja Milosevic
The Synthesis And Antimicrobial Activity Of \\\\Gamma-Butyrolactone Derivatives, Slobodan Sukdolak, Slavica Solujic-Sukdolak, Nenad Vukovic, Tanja Milosevic
Turkish Journal of Chemistry
This paper examines the synthesis of \gamma-butyrolactone compounds 2, 3, 4, 5, and 9, and their potential antimicrobial nature and ability. The structures of all the compounds mentioned above were determined and confirmed with elemental analyses, and IR, ^1H-NMR, and ^{13}C-NMR spectroscopy. The in vitro antimicrobial activity of compounds 2, 3, 4, 5, and 9 was examined and evaluated against the following pathogens: Enterobacter aerogenes, Enterobacter cloacae, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus agalactiae, Aspergillus niger, and Candida albicans. Compound 5 (20 mg/mL) demonstrated high antimicrobial activity against S. epidermidis, which was closely comparable to the antimicrobial …
Studies On The Chemical Constituents Of Thymus Serpyllum, Shahid Aziz, . Habib-Ur-Rehman
Studies On The Chemical Constituents Of Thymus Serpyllum, Shahid Aziz, . Habib-Ur-Rehman
Turkish Journal of Chemistry
Phytochemical investigations on the methanolic extract of Thymus serpyllum resulted in the isolation of 2 new compounds, 3-ketopentatriacontanoic acid (1) and 27-ketotriacontanol (2). The extract also afforded 3 known compounds, 3 \beta-hydroxyolean-12-en- 28-oic acid (3), 3-O-\beta-D-glucopyranosyl-sitosterol (4), and dihydroursonic acid (5), detected for the first time from Thymus serpyllum. The structures of the new compounds were elucidated by spectroscopic methods, while the known compounds were identified on the basis of their spectral data and literature evidence. The hexane and ethyl acetate soluble portions of the methanolic extract showed significant antifungal activity, whereas the chloroform soluble portion and the remaining methanol …
Hydrogenation Of Citral Over Ni And Ni-Sn Catalysts, Hi̇lal Aykaç, Selahatti̇n Yilmaz
Hydrogenation Of Citral Over Ni And Ni-Sn Catalysts, Hi̇lal Aykaç, Selahatti̇n Yilmaz
Turkish Journal of Chemistry
Liquid phase citral hydrogenation over zeolite-supported monometallic Ni and bimetallic Ni-Sn catalysts was studied. The zeolite support materials were Na-Y, Na-mordenite, and clinoptilolite. Ni and Sn contents of the monometallic and bimetallic catalysts were 8.1-9.2 wt% and 0.46 wt%, respectively. The type of the zeolite support affected the activity and selectivity of the catalysts differently. The main product of the citral hydrogenation reaction was citronellal, for both monometallic (84.5% yield) and bimetallic (44.5% yield) catalysts. The addition of promoter increased the selectivity to unsaturated alcohols (geraniol+nerol), i.e. it changed from 0.9% to 6.3% over mordenite and from 0.9% to 2.1% …
On-Line Incorporation Of Cloud Point Extraction In Flame Atomic Absorption Spectrometric Determination Of Silver, Nasser Dalali, Nasrin Javadi, Yadvendra Kumar Agawal
On-Line Incorporation Of Cloud Point Extraction In Flame Atomic Absorption Spectrometric Determination Of Silver, Nasser Dalali, Nasrin Javadi, Yadvendra Kumar Agawal
Turkish Journal of Chemistry
A cloud point extraction method was incorporated into a flow injection system, coupled with flame atomic absorption spectrometry, for determination of trace amounts of silver. The analyte in the aqueous solution was acidified with 0.2 mol L^{-1} sulfuric acid and complexed with dithizone. The cloud point extraction was performed using the non-ionic surfactant Triton X-114. After obtaining the cloud point, the surfactant-rich phase containing the dithizonate complex was collected in a mini-column packed with cotton wool. Then the complex was eluted by passing THF through the column and silver content was determined by flame atomic absorption spectrometry. All the chemical …
New Flame-Retardant Poly(Ester-Imide)S Containing Phosphine Oxide Moieties In The Main Chain: Synthesis And Properties, Khalil Faghihi
New Flame-Retardant Poly(Ester-Imide)S Containing Phosphine Oxide Moieties In The Main Chain: Synthesis And Properties, Khalil Faghihi
Turkish Journal of Chemistry
Six new flame-retardant poly(ester-imide)s (9a-f) with high inherent viscosity and containing phosphine oxide moieties in the main chain were synthesized from the polycondensation reaction of N,N-(3,3-diphenylphenyl phosphine oxide) bistrimellitimide diacid chloride (7) with 6 aromatic diols (8a-f) by 2 different methods:--solution and microwave-assisted polycondensation. The results showed that compared to solution polycondensation, the microwave-assisted polycondensation reaction using a domestic microwave oven proceeded rapidly and was completed within about 9-12 min. All of the obtained polymers were fully characterized by means of elemental analysis, viscosity measurement, solubility testing, and FT-IR spectroscopy. Thermal properties and flame retardant behavior of the PEIs (9a-f) …
Production Of (S)-(-)-1-(1´-Napthyl) Ethanol By Rhodotorula Glutinis Isolate Using Ram Horn Peptone, Esabi̇ Başaran Kurbanoğlu, Kani̇ Zi̇lbeyaz, Namudar I. Kurbanoğlu, Mesut Taşkin, Hamdullah Kiliç
Production Of (S)-(-)-1-(1´-Napthyl) Ethanol By Rhodotorula Glutinis Isolate Using Ram Horn Peptone, Esabi̇ Başaran Kurbanoğlu, Kani̇ Zi̇lbeyaz, Namudar I. Kurbanoğlu, Mesut Taşkin, Hamdullah Kiliç
Turkish Journal of Chemistry
The bioreduction of 1-acetonaphthone 1 by locally isolated Rhodotorula glutinis strains using ram horn peptone (RHP) gave (S)-(-)-1-(1´-naphthyl) ethanol (2), an important pharmaceutical intermediate. R. glutinis strains were isolated from the water of fermented Salix leaves. Optimum fermentation conditions for the production of 2 were 200 rpm, 32 °C, and pH 6.5. The production of 2 with excellent enantiomeric excess (>99%), and good conversion (100%) and yield (78%) under optimum conditions was achieved up to preparative scale via a fermenter. Wide temperature, pH, time, and agitation ranges did not affect the enantiomeric excess (ee) of the bioreduction product. A …
Hydrogenation Of Citral Over Pt And Pt-Sn Catalysts, Hi̇lal Aykaç, Selahatti̇n Yilmaz
Hydrogenation Of Citral Over Pt And Pt-Sn Catalysts, Hi̇lal Aykaç, Selahatti̇n Yilmaz
Turkish Journal of Chemistry
Hydrogenation of citral on monometallic (Pt) and bimetallic (Pt-Sn) catalysts was investigated. It was found that the catalyst activities and product distributions were different over Na-Y and Clino supports. Among monometallic catalysts, Pt/Na-Y was more selective to citronellol (3.9%) and unsaturated alcohols, geraniol and nerol, (14.1%). Sn addition increased the catalyst activities. However, its effect on product distribution differed. Yield of geraniol+nerol changed from 5.1% to 19.7% over Clino. However, selectivity to unsaturated alcohols over Na-Y decreased when it was prepared as a bimetallic catalyst support. Unsaturated alcohol formation was favored when there was a metal support interaction over monometallic …
Comparison Of Catalytic Activities Of Carbon Supported Pt And Pt-Ru Catalysts For Methanol Oxidation In Neutral And Basic Media By Cyclic Voltammetry, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza
Comparison Of Catalytic Activities Of Carbon Supported Pt And Pt-Ru Catalysts For Methanol Oxidation In Neutral And Basic Media By Cyclic Voltammetry, Abdul Sattar Ali Khan, Riaz Ahmed, Muhammad Latif Mirza
Turkish Journal of Chemistry
The catalytic activities of an equal amount of 3 different carbon supported catalysts containing 10% Pt, 20% Pt + 10% Ru, and 30% Pt were evaluated in neutral and basic media for methanol oxidation by cyclic voltammetry. The prominent oxidation peak for methanol appeared in the forward anodic sweep at around 1.0 V in neutral medium, while in basic medium it appeared at significantly lower potential close to 0.2 V. The peak current for methanol oxidation was higher on a catalyst containing higher Pt loading. The comparison of polarization behavior of 20% Pt + 10% Ru and 30% Pt catalysts …
Preparation Of Palladium Composite Membranes On Pore Structure Modified And Non-Modified Supports By Electroless Plating Procedure, Sali̇ha Kiliçarslan, Osman Muzaffer Afyon, Meltem Doğan
Preparation Of Palladium Composite Membranes On Pore Structure Modified And Non-Modified Supports By Electroless Plating Procedure, Sali̇ha Kiliçarslan, Osman Muzaffer Afyon, Meltem Doğan
Turkish Journal of Chemistry
The effects of pore structure of the support on the plating morphology, thickness, and composition were investigated in an electroless plating procedure. Some of the plating studies were carried out directly on commercially available porous glass supports, while others were performed on modified supports. Two modification steps with alumina were applied on tubular supports. Formation of a 60-\mu m-thick layer on the modified support was detected by SEM analysis after the first 2 plating steps, while layer formation was not observed on the non-modified support. It was shown that the formation of a new layer started on the modified support, …
Synthesis And Biological Activity Of Allosteric Modulators Of Gaba_B Receptors. Part 4. Synthesis Of Potentially Fluorescent Acridines And Conformationally Restricted N-(Arylpropyl)-1-Arylethylamines, Jabbar Khalafy, Rolf H. Prager, Ni Made Puspawati
Synthesis And Biological Activity Of Allosteric Modulators Of Gaba_B Receptors. Part 4. Synthesis Of Potentially Fluorescent Acridines And Conformationally Restricted N-(Arylpropyl)-1-Arylethylamines, Jabbar Khalafy, Rolf H. Prager, Ni Made Puspawati
Turkish Journal of Chemistry
A series of 8 new derivatives of fendiline was prepared for evaluation as allosteric modulators of GABA_B receptors: 4 based on acridine and 4 with restricted distance between the 2 aryl moieties.
Potentiometric Determination Of The Stability Constants Of Lanthanide Complexes With Iminodiacetic Acid In Water And Dioxane-Water Mixtures, Sevgi̇ Arzik, Ebru Mavi̇oğlu Ayan, A. Sedat Çelebi̇
Potentiometric Determination Of The Stability Constants Of Lanthanide Complexes With Iminodiacetic Acid In Water And Dioxane-Water Mixtures, Sevgi̇ Arzik, Ebru Mavi̇oğlu Ayan, A. Sedat Çelebi̇
Turkish Journal of Chemistry
The protonation constants of iminodiacetic acid (H_2 ida) and the stability constants of its complexes with Nd(III), Sm(III), Gd(III), Dy(III), and Er(III) ions at metal/ligand mole ratios of 1:1, 1:2, and 1:3 at 25 °C and 0.1 M ionic strength in aqueous medium and 20%, 45%, and 70% w/w dioxane-water mixtures were determined by the potentiometric method using the BEST computer program. The stability constants of the complexes that formed increased as the dioxane content increased. The stability of all the analogues' complexes, both in aqueous medium and in dioxane-water mixtures, were in the order of Nd(III) < Sm(III) < Gd(III) < Dy(III) < Er(III).
Examination Of The Electroanalytic Performance Of Carbon Nanotube (Cnt) Modified Carbon Paste Electrodes As Xanthine Biosensor Transducers, Ülkü Anik, Meli̇ha Çubukçu
Examination Of The Electroanalytic Performance Of Carbon Nanotube (Cnt) Modified Carbon Paste Electrodes As Xanthine Biosensor Transducers, Ülkü Anik, Meli̇ha Çubukçu
Turkish Journal of Chemistry
The effect of multi-walled carbon nanotube (MWCNT) and single-wall carbon nanotube (SWCNT) on carbon paste electrode (CPE) electrochemical response was examined by introducing various portions of CNT into the CPE. The optimum electrode structure was determined by comparing the prepared electrodes´ electroanalytical performance towards ferricyanide. Then these optimum compositions were modified with xanthine oxidase (XO) enzyme for obtaining a xanthine biosensor. After the optimization of biosensor working conditions, the developed systems were characterized for xanthine. Linearity was obtained in the concentration range between 1 and 100 \mu M xanthine with an RSD value of 3.35% for MWCNT-CPE, while with SWCNT-CPE …
Microwave-Assisted Synthesis Of 1,4´-Diazaflavone And N-Alkyl Derivative Pigments With Anti-Microbial Activity, Nuran Yayli, Osman Üçüncü, Nuretti̇n Yayli, Emi̇ne Demi̇r, Zi̇hni̇ Demi̇rbağ
Microwave-Assisted Synthesis Of 1,4´-Diazaflavone And N-Alkyl Derivative Pigments With Anti-Microbial Activity, Nuran Yayli, Osman Üçüncü, Nuretti̇n Yayli, Emi̇ne Demi̇r, Zi̇hni̇ Demi̇rbağ
Turkish Journal of Chemistry
1,4'-Diazaflavone pigment (2) was synthesized by a simple environmentally friendly microwave-assisted one-pot method for the cyclization of 2'-amino (E)-4''-aza-chalcone (1) under solventless conditions using K-10 clay. In addition, 10 new N-alkyl (C_{5-12, 14-15}) substituted 1,4' -diazaflavonium bromide pigments (3-12) were prepared from compound 2 or directly from compound 1, with corresponding alkyl halides in acetonitrile under reflux. The anti-microbial activity of compounds 1-12 was tested. The N-alkyl substituted 1,4' -diazaflavonium bromides (3-12) showed good antimicrobial activity against the gram-positive bacteria tested with minimal bactericidal concentration (MBC) values for the reference antibiotic kanamycin. The optimum length of the alkyl chain for …
Synthesis And Cloning Of A Small Bacillus Pheromone Gene (Comx_{Ro-B-2}) By Primer-Dimer Formation With Pcr, Devri̇m Demi̇r Dora, Tanil Kocagöz, Fi̇li̇z Öner
Synthesis And Cloning Of A Small Bacillus Pheromone Gene (Comx_{Ro-B-2}) By Primer-Dimer Formation With Pcr, Devri̇m Demi̇r Dora, Tanil Kocagöz, Fi̇li̇z Öner
Turkish Journal of Chemistry
ComX pheromone is the major extracellular signaling peptide stimulating transformation in response to high cell density in Bacillus species. In this study, Bacillus mojavensis ComX_{(RO-B-2)} pheromone gene was cloned to pGEMT-Easy vector based on TA cloning of PCR products. The gene encoding 11 amino acid peptides of Bacillus mojavensis RO-B-2 strain ComX pheromone (GLQIYTNWVPS) was obtained by PCR amplification of 2 primers complementary to each other at their 3' end. This eliminated the need for the original bacterial gene as DNA template for PCR. The amplified PCR products were ligated directly without any modification by T4 DNA ligase into pGEMT-Easy …
Synthesis Of New Azo Dyes And Copper(Ii) Complexes Derived From Barbituric Acid And 4-Aminobenzoylhydrazone, Bülent Kirkan, Ramazan Gup
Synthesis Of New Azo Dyes And Copper(Ii) Complexes Derived From Barbituric Acid And 4-Aminobenzoylhydrazone, Bülent Kirkan, Ramazan Gup
Turkish Journal of Chemistry
Four new azo dyes, L^1, L^2, L^3, and L^4, were prepared by linking benzaldehyde p-aminobenzoylhydrazone (3) and p-hydroxybenzaldehyede p--aminobenzoylhydrazone (4) to barbituric acid and 1,3-dimethylbarbituric acid through diazo-coupling reactions. Reactions of the azo-dyes with copper chloride and bidentate ligand, 1,10-phenanthroline, produced mixed-ligand dinuclear complexes with general stoichiometry [Cu_2L(phen)_2]Cl_2 (7, 8, 9, and 10). The structures of both azo dyes and their complexes were identified by elemental analyses, FT-IR, ^1H-NMR, UV-VIS, magnetic susceptibility, and mass spectral data.
Investigation Of Solid State Synthesis And Characterizations Of Novel Sodium Rare-Earth Oxyphosphates, Semi̇h Seyyi̇doğlu, Maci̇t Özenbaş, Ayşen Yilmaz
Investigation Of Solid State Synthesis And Characterizations Of Novel Sodium Rare-Earth Oxyphosphates, Semi̇h Seyyi̇doğlu, Maci̇t Özenbaş, Ayşen Yilmaz
Turkish Journal of Chemistry
A new orthorhombic phase of Na_2LaOPO_4 (sodium lanthanum oxyphosphate), and novel Na_2NdOPO_4 (sodium neodymium oxyphosphate), Na_2SmOPO_4 (sodium samarium oxyphosphate) were synthesized by solid state reactions of Na_2CO_3, NH_4H_2PO_4, and Ln_2O_3 (Ln = La, Nd, and Sm). The unit cell dimensions were calculated using their X-ray powder diffraction data, which were a = 13.60(1), b = 12.71(1), and c = 6.96(1) Å, a = 13.466(5), b = 12.547(6), and c = 6.932(5) Å, and a = 13.54(1), b = 12.577(8), and c = 7.047(5) Å, respectively, and the probable space group was Pmm2. Using the same procedure orthorhombic Na_2DyOPO_4 (sodium dysprosium …