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Synthesis And Swelling Behavior Of Starch-Poly (Sodium Acrylate-Co-Acrylamide) Superabsorbent Hydrogel, Mohammad Sadeghi, Hossein Hosseinzadeh
Synthesis And Swelling Behavior Of Starch-Poly (Sodium Acrylate-Co-Acrylamide) Superabsorbent Hydrogel, Mohammad Sadeghi, Hossein Hosseinzadeh
Turkish Journal of Chemistry
Superabsorbent polymers based on starch (St) and polyacrylonitrile (PAN) were prepared by alkaline hydrolysis of the physical mixture of St and PAN in aqueous solution. The nitrile groups of PAN were completely converted to a mixture of hydrophilic carboxamide and carboxylate groups during alkaline hydrolysis, followed by in situ cross-linking of the PAN chains by the alkoxide ions of St. A proposed mechanism for hydrogel formation was suggested and the structure of the product was established using FTIR spectroscopy. Moreover, morphology of the samples was examined by scanning electron microscopy. The factors that influenced the swelling capacity of the hydrogels …
Efficient Synthesis Of Imidazole Derivatives: An Important Synthon For The Preparation Of Biologically Active Compounds, Asghar Davood, Eskandar Alipour, Abbas Shafiee
Efficient Synthesis Of Imidazole Derivatives: An Important Synthon For The Preparation Of Biologically Active Compounds, Asghar Davood, Eskandar Alipour, Abbas Shafiee
Turkish Journal of Chemistry
4(5)-Chloro-imidazole-5(4)-carboxaldehyde derivatives are important precursors for the preparation of biologically active compounds. We developed a simple, novel, and efficient method for the synthesis of these compounds. The chemistry described is amenable to large-scale use and is flexible enough to allow the preparation of analogs.
One-Step Synthesis Of Hyaluronic Acid-Based (Sub)Micron Hydrogel Particles: Process Optimization And Preliminary Characterization, Nurettin Sahiner, Xinqiao Jia
One-Step Synthesis Of Hyaluronic Acid-Based (Sub)Micron Hydrogel Particles: Process Optimization And Preliminary Characterization, Nurettin Sahiner, Xinqiao Jia
Turkish Journal of Chemistry
Hyaluronic acid (HA)-based (sub)micron hydrogel particles were synthesized by crosslinking virgin HA with divinyl sulfone (DVS) in sodium bis(2-ethylhexyl)sulfosuccinate (AOT) reverse micelle systems under basic conditions. Experimental parameters including HA molecular weight, solution concentration, and reaction time were systematically varied in order to obtain well defined hydrogel particles. The use of a cosurfactant, 1-heptanol (1-HP), had a profound effect on the reaction kinetics and the particle morphology. The resulting particles exhibit negative charges on their surfaces. In vitro biocompatibility study indicates that these particles do not cause severe death to the cultured fibroblasts. These HA-based hydrogel particles are promising candidates …
Oxidative Cyclisation Of 3-Oxopropanenitriles Mediated Manganese(Iii) Acetate With 2-Thienyl Substituted Alkenes, Mehmet Yilmaz, Neşe Uzunali̇oğlu, Mehtap Yakut, A. Tarik Pekel
Oxidative Cyclisation Of 3-Oxopropanenitriles Mediated Manganese(Iii) Acetate With 2-Thienyl Substituted Alkenes, Mehmet Yilmaz, Neşe Uzunali̇oğlu, Mehtap Yakut, A. Tarik Pekel
Turkish Journal of Chemistry
The oxidative cyclisation of 3-oxopropanenitriles 1a-g with alkenes 2a-c containing 2-thienyl group by manganese(III) acetate was studied. Treatment of 3-oxopropanenitriles 1a-d with 2-[(E)-2-phenylvinyl] thiophene 2a gave 4-phenyl-5-(2-thienyl)-4,5-dihydrofuran-3-carbonitriles 3a-d in moderate yields (52%-60%). 5-(2-thienyl) substituted 4,5-dihydrofuran-3-carbonitriles 3e-i were obtained by the oxidative cyclisation of these 3-oxopropanenitriles with 2-[(E)-1-methyl-2- phenylvinyl]thiophene 2b in good yields (54%-68%). In addition, the reactions of 2-(1-phenylvinyl)thiophene 2c with various 3-oxopropanenitriles produced 4,5-dihydrofurans 3j-n containing heterocycle in 77%-91% yields.
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 …
Solid Phase Extraction Of Cadmium In Edible Oils Using Zinc Piperazinedithiocarbamate And Its Determination By Flame Atomic Absorption Spectrometry, Mehtap Yağan Aşci, Ayşegül Efendi̇oğlu, Beki̇r Bati
Solid Phase Extraction Of Cadmium In Edible Oils Using Zinc Piperazinedithiocarbamate And Its Determination By Flame Atomic Absorption Spectrometry, Mehtap Yağan Aşci, Ayşegül Efendi̇oğlu, Beki̇r Bati
Turkish Journal of Chemistry
A method was developed for preconcentration of cadmium with zinc-piperazinedithiocarbamate (ZnPDC) in edible oils and its determination by flame atomic absorption spectrometer (FAAS). The preconcentration method is based on the adsorption of the Cd(II) on to ZnPDC and the elution of them with mercury(II) nitrate. The accuracy of the method was tested with standard reference material (CONOSTAN S-21) and Cd added samples. Under optimum conditions, the recovery and the detection limit for cadmium were 99.67% (\pm 0.67) and 0.028 mg/L, respectively. The calibration curve was linear over the concentration range 0.1-3.0 mg/L (r^2 = 0.9979). The proposed method was applied …
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 …
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 …
Synthesis And Antimicrobial Activity Of Some 3(2h)-Pyridazinone And 1(2h)-Phthalazinone Derivatives, Deni̇z S. Doğruer, Ti̇jen Önkol, Semi̇ha Özkan, Selda Özgen, M. Fethi̇ Şahi̇n
Synthesis And Antimicrobial Activity Of Some 3(2h)-Pyridazinone And 1(2h)-Phthalazinone Derivatives, Deni̇z S. Doğruer, Ti̇jen Önkol, Semi̇ha Özkan, Selda Özgen, M. Fethi̇ Şahi̇n
Turkish Journal of Chemistry
Some 3(2H)-pyridazinone and 1(2H)-phthalazinone derivatives were synthesized. The structures of these new compounds were confirmed by IR, ^1H-NMR, mass spectrum, and elemental analysis. The synthesized compounds were evaluated for their antibacterial activity against various gram-positive and gram-negative strains of bacteria and their clinical isolates and for their antimycobacterial activity against M. tuberculosis H37Rv. The results showed that the synthesized compounds were generally active against B. subtilis and its clinical isolate. Among the target compounds, compound 14c exhibited the best antibacterial activity, with a MIC value of 15.62 \mu g/mL against B. subtilis. Compound 15e had the highest antimycobacterial activity.
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 …
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 …
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 …
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 …
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 …
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 …
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 …
Synthesis And Selective Extractant Properties Of A Calixarene Thioether Derivative And Its Oligomeric Analogue, Gülderen Uysal Akkuş, Selma Aslan, F. Fulya Taktak, Shahabuddin Memon
Synthesis And Selective Extractant Properties Of A Calixarene Thioether Derivative And Its Oligomeric Analogue, Gülderen Uysal Akkuş, Selma Aslan, F. Fulya Taktak, Shahabuddin Memon
Turkish Journal of Chemistry
Herein we report the synthesis of a novel calix[4]arene thioether derivative (4) and its oligomeric analogue (5). The liquid-liquid extraction properties of these compounds towards the selected metal cations were evaluated, and it was concluded, based on our observations, that these compounds demonstrated remarkable affinity towards the selected metal cations. Nevertheless, is a good extractant and very selective for Hg^{2+} ions, whereas, in the case of its oligomeric analogue 5, the situation is quiet different. It was observed that 5 could not efficiently retain the parent selective behavior by extracting all of the selected metal ions from the aqueous to …
Co Oxidation Over Mono And Bi-Metallic Sequentially Impregnated Pd-Pt Catalysts, Sarp Kaya, Deni̇z Üner
Co Oxidation Over Mono And Bi-Metallic Sequentially Impregnated Pd-Pt Catalysts, Sarp Kaya, Deni̇z Üner
Turkish Journal of Chemistry
The CO oxidation capability of sequentially impregnated Pd-Pt/\gamma -Al_2O_3 bimetallic catalysts was tested. The CO oxidation light-off curves were hierarchically spaced between monometallic Pd and monometallic Pt, which showed the highest and lowest activity, respectively, indicating that sequential impregnation did not result in the formation of bimetallic particles, but that the catalysts remained as monometallic entities over the support surface. An investigation of the effect of CO partial pressure on the reaction rates over monometallic catalysts indicated that in the presence of excess CO the surface of Pt was poisoned. On the other hand, in the presence of excess CO …
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 …
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) …
Synthesis And Properties Of Novel Photosensitive Poly(Amide-Imide)S Containing Chalcone Moiety And Aromatic Diamines In The Main Chain, Khalil Faghihi, Zohreh Mozafari
Synthesis And Properties Of Novel Photosensitive Poly(Amide-Imide)S Containing Chalcone Moiety And Aromatic Diamines In The Main Chain, Khalil Faghihi, Zohreh Mozafari
Turkish Journal of Chemistry
Six new poly(amide-imide)s were synthesized by the polycondensation reaction of 1,3-bis[4,4'-bis(trimellityimido) phenyl]-2-propenone (6) with 3,3'-diamino diphenyl sulfone (7a), 4,4'-diamino diphenyl sulfone (7b), 4,4'-diamino diphenyl ether (7c), 1,5-diamino naphthalene (7d), 6-phenyl-1,3,5-triazine (7e), and 6-choloro-1,3-diazine (7f) in a medium consisting of N-methyl-2- pyrrolidone, triphenyl phosphite, calcium chloride, and pyridine. The polycondensation reaction produced a series of novel poly(amide-imide)s (8a-f) in high yield and with inherent viscosities between 0.42 and 0.62 dL/g. The resulting polymers were characterized by elemental analysis, viscosity measurement, solubility testing, thermo-gravimetric analysis (TGA & DTG), FT-IR, and UV-VIS spectroscopy.