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- Keyword
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- 1 (5)
- 3 (4)
- 2 (3)
- Biodiesel (3)
- 4 (2)
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- 4-Thiadiazole (2)
- Anti-Helicobacter pylori activity. (2)
- Antibacterial activity. (2)
- Dithienylpyrrole (2)
- Fuel cell (2)
- Heterogeneous catalyst (2)
- Iridoid glycosides (2)
- Metal complexes (2)
- Nitrofuran (2)
- Phenol (2)
- 1'-dinaphthalene (BINOL) (1)
- 1-(4-Dimethyl aminophenyl)-2-(5H-phenanthridine-6-ylidene)-ethanone (1)
- 1-b]furan; Benzofuran; Ketoxime. (1)
- 10-perylenetetracarboxylic diimide (1)
- 2'-binaphthylene phosphorochloridite (BINOL-PCl) (1)
- 2'-dihydroxy-1 (1)
- 2-a]pyrrolidin- 2-one (1)
- 2-cyclic diketones (1)
- 2-methyl-1-indanone (1)
- 2\alpha (1)
- 2\beta (1)
- 3-component reaction. (1)
- 3-methly-1-indanone (1)
- 3-thiazoles (1)
- 3\alpha (1)
Articles 1 - 30 of 82
Full-Text Articles in Physical Sciences and Mathematics
Antioxidant Galloylated Flavonoids From Geranium Tuberosum L. Subsp. Tuberosum, Di̇dem Şöhretoğlu, Mahmut Koray Sakar, Suna Atasayar Sabuncuoğlu, Hi̇lal Özgüneş, Olov Sterner
Antioxidant Galloylated Flavonoids From Geranium Tuberosum L. Subsp. Tuberosum, Di̇dem Şöhretoğlu, Mahmut Koray Sakar, Suna Atasayar Sabuncuoğlu, Hi̇lal Özgüneş, Olov Sterner
Turkish Journal of Chemistry
Phytochemical investigations on the most active EtOAc extract led to the isolation of 9 flavonoids [quercetin (1), quercetin 3-O-\beta-glucopyranoside (2), quercetin 3-O-\beta-galactopyranoside (3), quercetin 3-O-(2''-O-galloyl)-\beta-glucopyranoside (4), quercetin 3-O-(2''-O-galloyl)-\beta-galactopyranoside (5), quercetin 3-O-(6''-O-galloyl)-\beta-glucopyranoside (6), quercetin 3-O-(6''-O-galloyl)-\beta-galactopyranoside (7), quercetin-3-O-\alpha -arabinofuranoside (8), and quercetin-3-O-\alpha-rhamnopyranosyl-(1\to 6)-\beta-glucopyranoside (9)] and a simple phenolic compound (methyl gallate) (10). The structures of the compounds were elucidated by 1- and 2-dimensional NMR techniques (^1H, ^{13}C, COSY, HMBC, and HMQC) and ESI-TOF-MS spectrometry. H_2O_2-induced lipid peroxidation inhibitor effects in human red blood cells of different extracts of G. tuberosum L. subsp. tuberosum aerial parts were also investigated. All the compounds tested …
Spectroscopic Studies And Hartree-Fock Ab Initio Calculations Of A Substituted Amide Of Pyrazine-2-Carboxylic Acid - C_{16}H_{18}Cln_3o, Chacko Yohannan Panicker, Hema Tresa Vanghese, Thaha Thansani
Spectroscopic Studies And Hartree-Fock Ab Initio Calculations Of A Substituted Amide Of Pyrazine-2-Carboxylic Acid - C_{16}H_{18}Cln_3o, Chacko Yohannan Panicker, Hema Tresa Vanghese, Thaha Thansani
Turkish Journal of Chemistry
A substituted amide of pyrazine-2-carboxylic acid was prepared and the IR spectrum was recorded and analysed. The compound prepared was identified by NMR and mass spectra. The vibrational frequencies of the title compound were computed using the Hartree-Fock level of theory using the 6-31G* basis set and compared with the experimental data. The red shift of the NH stretching frequency indicates weakening of the NH bond. The splitting of the NH stretching bond is due to Davidov coupling between neighbouring units. The first hyperpolarizability, infrared intensities, and Raman activities are reported. Methyl substitution affects all the carbon-nitrogen and carbon-carbon bond …
The Synthesis, Characterization And Energy Transfer Efficiency Of A Dithienylpyrrole And Bodipy Based Donor-Acceptor System, Taner Atalar, Ati̇lla Ci̇haner, Fati̇h Algi
The Synthesis, Characterization And Energy Transfer Efficiency Of A Dithienylpyrrole And Bodipy Based Donor-Acceptor System, Taner Atalar, Ati̇lla Ci̇haner, Fati̇h Algi
Turkish Journal of Chemistry
A dithienylpyrrole-BODIPY based donor-acceptor system with 1,4-phenylene spacer as a model system for energy transfer was designed and synthesized. Absorption and emission spectra have revealed an efficient resonance energy transfer from dithienylpyrrole as donor to BODIPY as acceptor.
Microwave-Assisted Synthesis Of Some Metal-Free Phthalocyanine Derivatives And A Comparison With Conventional Methods Of Their Synthesis, Özlem Seven, Bi̇rcan Di̇ndar, Burak Gülteki̇n
Microwave-Assisted Synthesis Of Some Metal-Free Phthalocyanine Derivatives And A Comparison With Conventional Methods Of Their Synthesis, Özlem Seven, Bi̇rcan Di̇ndar, Burak Gülteki̇n
Turkish Journal of Chemistry
Synthesis of metal-free 2,9(10),16(17),23(24)-tetra(3,5- dimethylphenoxy) phthalocyanine, 2,9(10),16(17), 23(24)-tetra(4- tert-butylphenoxy) phthalocyanine, and 2,9(10),16(17),23(24)-tetra(3,5- di-tert-butyl-4-hydroxyphenyl) phthalocyanine was carried out via microwave irradiation. Furthermore, pentanol and lithium were used for the first time in the synthesis of metal-free phthalocyanine under microwave irradiation as a solvent and a base-catalyst, respectively. The microwave irradiation experiments were performed in a MARS5 with a CEM XP-1500 vessel. In addition, these compounds were obtained with conventional heating procedures to compare them with those obtained with microwave irradiation. The compounds were characterized by elemental and spectroscopic analysis, including UV-Vis, H NMR, FT-IR, and MALDI-TOF mass data. In particular, both …
Study Of The Polymerization Of Methyl Methacrylate Initiated By Thioxanthone Derivatives: A Magnetic Field Effect, Sevnur Keski̇n, Meral Aydin, Igor Khudyakov, Nergi̇z Arsu
Study Of The Polymerization Of Methyl Methacrylate Initiated By Thioxanthone Derivatives: A Magnetic Field Effect, Sevnur Keski̇n, Meral Aydin, Igor Khudyakov, Nergi̇z Arsu
Turkish Journal of Chemistry
Free radical photopolymerization of methyl methacrylate (MMA) initiated by 2-mercaptothioxanthone (TX-SH), thioxanthone-thioacetic acid (TXSCH_2COOH), and thioxanthone-carboxymethoxy acetic acid (TXOCH_2COOH) as so called one-component initiators was performed with and without an external magnetic field (MF). These initiators contain light-absorbing and electron/hydrogen-donating fragments in one molecule and do not require an additional hydrogen donor, and initiate the polymerization of MMA in the air. Polymerization experiments were performed in solutions with 3 different optical densities at \lambda 365 nm, where the photoinitiator absorbs. It was observed that application of MF leads to both larger conversion and higher molecular weight of the prepared PMMA, …
Synthesis, Spectral Characterization, And Antimicrobial Activity Of Arsenic(Iii) And Bismuth(Iii) Tri[3(2´-Hydroxyphenyl)-5-(4-Subsituted Phenyl)Pyrazolinates], Umesh Nath Tripathi, Afshan Siddqui, Jeeven Singh Solanki, Mohammad Safi Ahmad, Arpan Bhardwaj, Tulsi Ram Thapak
Synthesis, Spectral Characterization, And Antimicrobial Activity Of Arsenic(Iii) And Bismuth(Iii) Tri[3(2´-Hydroxyphenyl)-5-(4-Subsituted Phenyl)Pyrazolinates], Umesh Nath Tripathi, Afshan Siddqui, Jeeven Singh Solanki, Mohammad Safi Ahmad, Arpan Bhardwaj, Tulsi Ram Thapak
Turkish Journal of Chemistry
Arsenic(III) tripyrazolinates and bismuth(III) tripyrazolinates of the type M(C_{15}H_{12}N_2OX)_3 [where C_{15}H_{12}N_2OX = 3(2'-hydroxyphenyl)-5-(4-substituted phenyl)pyrazoline] have been synthesized by the reaction of MCl_3 and sodium salt of pyrazolines in 1:3 molar ratio in anhydrous benzene at elevated temperature. These newly synthesized derivatives have been characterized by elemental analysis (C, H, N, As, and Bi), molecular weight measurement, spectral [IR and multinuclear NMR (^1H & ^{13}C)] and x-ray diffraction studies. The bonding mode of pyrazolines and coordination no. of arsenic(III) and bismuth(III) in these derivatives have been discussed. Antibacterial and antifungal potential of free pyrazoline and some arsenic(III) tripyrazolinates and bismuth(III) tripyrazolinates …
A Density Functional Theory Study Of Oxidation Of Benzene To Phenol By N_2o On Fe- And Co-Zsm-5 Clusters, Mehmet Ferdi̇ Fellah, Işik Önal
A Density Functional Theory Study Of Oxidation Of Benzene To Phenol By N_2o On Fe- And Co-Zsm-5 Clusters, Mehmet Ferdi̇ Fellah, Işik Önal
Turkish Journal of Chemistry
Density functional theory (DFT) calculations were carried out in the study of oxidation of benzene to phenol by N_2O on relaxed [(SiH_3)_4AlO_4M] (where M=Fe, Co) cluster models representing Fe- and Co-ZSM-5 surfaces. The catalytic cycle steps are completed for both Fe-ZSM-5 and Co-ZSM-5 clusters. The general trend of the results that were obtained in terms of activation barriers for the Fe-ZSM-5 cluster is in agreement with the experimental and theoretical literature. It was observed that the phenol formation step is the rate-limiting step for both clusters and Co-ZSM-5 surface has a lower activation barrier than the Fe-ZSM-5 surface (i.e. 35.82 …
Synthesis And In Vitro Anti-Helicobacter Pylori Activity Of 2-(Substituted Benzylthio)-5-(5-Nitro-2- Furyl)-1, 3, 4-Thiadiazole Derivatives, Negar Mohammadhosseini, Ali Asadipor, Bahram Letafat, Mohsen Vosooghi, Farideh Siavoshi, Abbas Shafiee, Alireza Foroumadi
Synthesis And In Vitro Anti-Helicobacter Pylori Activity Of 2-(Substituted Benzylthio)-5-(5-Nitro-2- Furyl)-1, 3, 4-Thiadiazole Derivatives, Negar Mohammadhosseini, Ali Asadipor, Bahram Letafat, Mohsen Vosooghi, Farideh Siavoshi, Abbas Shafiee, Alireza Foroumadi
Turkish Journal of Chemistry
Starting from (5-nitrofuran-2-yl)methylene diacetate, a new series of 2-[(substituted benzyl)thio]-5-(5-nitro-2-furyl)-1,3,4-thiadiazoles (6a-n) were synthesized and the structures of the compounds were determined using spectroscopic methods including mass spectrometry, ^1H-nuclear magnetic resonance, infrared spectroscopy, and elemental analysis. The in vitro anti-Helicobacter pylori activity of the synthesized compounds was evaluated by the disk diffusion method against the clinical isolates of Helicobacter pylori. The results indicated that most of the synthesized compounds exhibited significant inhibitory activity against H. pylori with respect to standard drug metronidazole. Compound 6l, containing the 2-chloro-6-fluorobenzylthio moiety, was the most potent compound tested.
Hydrogen Storage Via Physisorption: The Combined Role Of Adsorption Enthalpy And Entropy, Carlos Otero Arean, Barbara Bonelli, Montserrat Rodriguez Delgado, Edoardo Garrone
Hydrogen Storage Via Physisorption: The Combined Role Of Adsorption Enthalpy And Entropy, Carlos Otero Arean, Barbara Bonelli, Montserrat Rodriguez Delgado, Edoardo Garrone
Turkish Journal of Chemistry
Materials capable of cost-effective on-board hydrogen storage and delivery are currently being sought worldwide as a means to facilitate a hydrogen-based energy transition in the transportation sector. Among the solutions proposed, hydrogen storage by physisorption on porous solids constitutes a main avenue of research, and for intelligent design of such materials a detailed knowledge of gas adsorption thermodynamics is of the utmost importance. Analysis of the available data for hydrogen adsorption on alkali and alkaline-earth cation exchanged zeolites clearly shows that standard adsorption enthalpy (\Delta H^0) and entropy (\Delta S^0) are correlated, in the sense that larger \Delta S^0 values …
6-Ketomethyl Phenanthridine As A New Carrier In The Construction Of A Highly Selective Fe(Iii) Ion-Selective Membrane Electrode, R. Maleki, Reza Hosseinzadeh, Hossein Mehrabi, Ali Hassanzadeh, Khalil Farhadi
6-Ketomethyl Phenanthridine As A New Carrier In The Construction Of A Highly Selective Fe(Iii) Ion-Selective Membrane Electrode, R. Maleki, Reza Hosseinzadeh, Hossein Mehrabi, Ali Hassanzadeh, Khalil Farhadi
Turkish Journal of Chemistry
A new Fe^{3+} ion-selective membrane electrode based on 6-ketomethyl phenanthridine (6-KMPT) and 1-(4-dimethyl aminophenyl)-2-(5H-phenanthridine-6-ylidene)-ethanone, which were incorporated in a plasticized polyvinyl chloride (PVC) membrane, is described. The optimized membrane demonstrated a linear dynamic range of 5.2 \times 10^{-6}-1.0 \times 10^{-2} M, with a near Nernstian slope of 19.5 \pm 1.5 mV per decade and a detection limit of 1.2 \times 10^{-6} M. The electrode showed high selectivity for Fe^{3+} ions in comparison to other metal ions. The effect of membrane composition on the potential response of the electrode was studied. The best performance was observed for the membrane comprised of …
On The Structure Sensitivity Of Co Oxidation On Alumina Supported Pd--Pt Bimetallic Catalysts, Sarp Kaya, Ebru Erunal, Riad Shaltaf, Şi̇nasi̇ Elli̇altioğlu, Deni̇z Üner
On The Structure Sensitivity Of Co Oxidation On Alumina Supported Pd--Pt Bimetallic Catalysts, Sarp Kaya, Ebru Erunal, Riad Shaltaf, Şi̇nasi̇ Elli̇altioğlu, Deni̇z Üner
Turkish Journal of Chemistry
CO oxidation reaction was studied over monometallic and bimetallic palladium--platinum catalysts at 25:75, 50:50, and 75:25 Pd:Pt atomic fractions co-impregnated over a \gamma -Al_2O_3 support. The size of the metal particles, measured by modified hydrogen chemisorption, increased as the Pd fractions in the catalyst increased. The surface compositions and site metal distributions of the catalysts determined from Monte Carlo simulations indicated that Pd atoms segregated to the surface: at low Pd levels, Pd occupied preferentially 6 and 7 coordinated defect-like sites. As the Pd fraction increased, first 8 coordinated (100) and then 9 coordinated (111) planes were populated. At low …
A Facile Method For The Preparation Of Poly(4-Vinylpyridine) Nanoparticles And Their Characterization, Nurettin Sahiner
A Facile Method For The Preparation Of Poly(4-Vinylpyridine) Nanoparticles And Their Characterization, Nurettin Sahiner
Turkish Journal of Chemistry
Submicron size particles were synthesized from 4-vinylpyridine (4-VP) using an oil-in-water emulsion system. Divinyl benzene (DVB) and ethylene glycol dimethacrylate (EGDMA) were utilized as crosslinkers for the synthesis of p(4-VP) hydrogel nanoparticles in sodium dodecyl sulfate (SDS) surfactant systems. Characterization of the particles was made by transmission electron microscopy (TEM) and dynamic light scattering (DLS) methods. To render a positive charge, p(4-VP) particles were reacted with 1-bromo butane (1-BB).
Synthesis And Leishmanicidal Evaluation Of Novel 4-Substituted-2,2-Dimethyl-7-(Prop-2-Ynyloxy)Chromenes, Babak H. Alizadeh, Alireza Foroumadi, Susan K. Ardestani, Fatemeh Poorrajab, Abass Shafiee
Synthesis And Leishmanicidal Evaluation Of Novel 4-Substituted-2,2-Dimethyl-7-(Prop-2-Ynyloxy)Chromenes, Babak H. Alizadeh, Alireza Foroumadi, Susan K. Ardestani, Fatemeh Poorrajab, Abass Shafiee
Turkish Journal of Chemistry
Substituted 4-chromenes were synthesized via the Grignard coupling reaction of various substituted phenyl- and benzylmagnesium chlorides with 2,2-dimethyl-7-(prop-2-ynyloxy)chroman-4-one (1) in relatively good yield (60%-85%). The benzylic-substituted derivatives were a mixture of 2 exo and endo regioisomers, and the exo compounds were a mixture of E and Z isomers. Structural analysis of the exo and endo isomers, as well as E and Z of exo isomers were based on H-NMR, ^{13}C-NMR, and NOESY experiments. The synthetic compounds were examined for in vitro activity against Leishmania major and compound 9 (a, b) was the most active, with inhibitory activity of 36%.
A Convenient Synthesis Of 2-Azido And 2-Thiocyanato-2,3-Unsaturated Cyclic Ketones, Mesut Boz, Ömer Zai̇m, Hi̇lal Esen
A Convenient Synthesis Of 2-Azido And 2-Thiocyanato-2,3-Unsaturated Cyclic Ketones, Mesut Boz, Ömer Zai̇m, Hi̇lal Esen
Turkish Journal of Chemistry
2-Azido and 2-thiocyanato-2,3-unsaturated ketones were synthesized by utilizing functionalization of 5- or 6-membered cycloalkane-1,2-diones, namely diosphenols, with dimethylthiocarbomoyl chloride, which activates the system towards reaction with nucleophiles in acidic conditions. Replacement of the enolic oxygen of the diosphenols with azide and thiocyanate may be achieved by treating their dimethylthiocarbamates with sodium azide or potassium thiocyanate in boiling acetonitrile/acetic acid.
Ctab-Assisted Hydrothermal Synthesis And Magnetic Characterization Of Ni_Xco_{1-X}Fe_2o_4 Nanoparticles (X = 0.0, 0.6, 1.0), Abdulhadi̇ Baykal, Nermi̇n Kasapoğlu, Zehra Durmuş, Hüseyi̇n Kavas, Muhammet S. Toprak, Yüksel Köseoğlu
Ctab-Assisted Hydrothermal Synthesis And Magnetic Characterization Of Ni_Xco_{1-X}Fe_2o_4 Nanoparticles (X = 0.0, 0.6, 1.0), Abdulhadi̇ Baykal, Nermi̇n Kasapoğlu, Zehra Durmuş, Hüseyi̇n Kavas, Muhammet S. Toprak, Yüksel Köseoğlu
Turkish Journal of Chemistry
Nickel ferrite, Ni_xCo_{1-x}Fe_2O_4, NPs (where x = 0.0, 0.6 and 1.0) were successfully synthesized by a rapid and reproducible CTAB-assisted hydrothermal route. The influence of different hydrolyzing agents on the particle size and magnetic behavior of Ni_xCo_{1-x}Fe_2O_4 NPs was investigated. Particles showed very high phase purity and crystallinity in powder XRD analysis. Compositions of Co, Fe, and Ni in fabricated powders were also determined by AAS and results are in very good agreement with the targeted compositions. Samples hydrolyzed using NH_3 showed no significant changes in the particle size and morphology. NH_3 hydrolyzed samples were much smaller than their NaOH …
Mild And Efficient Iodination Of Aromatic Compounds With Trichloroisocyanuric Acid/I_2/Wet Sio_2 System, Batool Akhlaghinia, Marzieh Rahmani
Mild And Efficient Iodination Of Aromatic Compounds With Trichloroisocyanuric Acid/I_2/Wet Sio_2 System, Batool Akhlaghinia, Marzieh Rahmani
Turkish Journal of Chemistry
Iodoarenes can be obtained using trichloroisocyanuric acid/I_2/wet SiO_2 system at room temperature with high yield in CH_2Cl_2.
Nitric Oxide Releasing Derivatives Of [(2-Chloroethyl)Ureido] Benzoic Acid Esters As Potential Antineoplastic Agents, Hülya Akgün, Barkin Berk, Di̇lek Demi̇r Erol, Güldem Mercanoğlu, Ömer Faruk Bayrak, Berrak Çağlayan, Asli Dedeağaç, Işil Aksan Kurnaz
Nitric Oxide Releasing Derivatives Of [(2-Chloroethyl)Ureido] Benzoic Acid Esters As Potential Antineoplastic Agents, Hülya Akgün, Barkin Berk, Di̇lek Demi̇r Erol, Güldem Mercanoğlu, Ömer Faruk Bayrak, Berrak Çağlayan, Asli Dedeağaç, Işil Aksan Kurnaz
Turkish Journal of Chemistry
New series of [(2-chloroethyl)ureido] benzoic acids (compounds 3-8) and nitric oxide releasing derivatives of [(2-chloroethyl)ureido] benzoic acid esters (compounds 9-14) were synthesized as potential anti-cancer agents. These compounds were screened for their anti-proliferative activities on A549 (human lung carcinoma) cells and for their cytotoxic effects on L929 (mouse fibroblast) cells. The compounds 3-8 exhibited mild cytotoxic effects on L929 cells (cell viability from 100% to 85% -- 90% only) whereas they had very little anti-proliferative activities towards A549 lung carcinoma cells. On the other hand, compounds 10, 11, and 13 had some growth inhibition activity in A549 (human lung carcinoma) …
Synthesis And Antimicrobial And Antitumor Activity Of Some New [1,2,4] Triazole-5-One Derivatives, Yasemi̇n Ünver, Esra Düğdü, Kemal Sancak, Mustafa Er, Sengül Alpay Karaoğlu
Synthesis And Antimicrobial And Antitumor Activity Of Some New [1,2,4] Triazole-5-One Derivatives, Yasemi̇n Ünver, Esra Düğdü, Kemal Sancak, Mustafa Er, Sengül Alpay Karaoğlu
Turkish Journal of Chemistry
4-[Arylidene-amino]-3-thiophen-2-ylmethyl-4,5-dihydro[1,2,4]triazole-5-one compounds (3a-g) with Schiff base character were obtained from the reaction of 4-amino-3-thiophen-2-ylmethyl-4,5-dihydro-1H-[1,2,4]triazole-5-one (2) with various aldehydes. 1-(2-Oxo-2-phenyl-ethyl)-4-[arylidene-amino]-3-thiophen-2-ylmethyl-4,5- dihydro-1H-[1,2,4]triazole-5-ones (4a-g) were synthesized from the reaction of corresponding compounds 3a-g with bromoacetophenone. 1-(2-Hydroxy-2-phenyl-ethyl)- 3-thiophen-2-ylmethyl-4-[aryl-amino]4,5-dihydro-1H-[1,2,4]triazole-5-ones (5a-g) and 1-(2-hydroxy-2-phenyl-ethyl)-3-thiophen-2-ylmethyl-4-[arylidene-amino] 4,5-dihydro-1H-[1,2,4]triazole-5-ones (6b,d,e) were obtained from the selective reduction of 1-(2-oxo-2-phenyl-ethyl)-4-[arylidene-amino]-3-thiophen-2ylmethyl- 4,5-dihydro-1H-[1,2,4] triazole-5-ones (4) with NaBH_4. They were characterized by IR, H-NMR,^{13}C-NMR, and elemental analyses. Compounds 2, 3a, 3c, 3g, 4f, 5b, and 5g showed good antifungal activity against yeast-like fungi. Compounds selected by the National Cancer Institute (NCI, USA) were investigated for antitumor activity.
Quantitative Structure--Retention Study Of Some 2,4-Dioksotetrahydro- 1,3--Thiazole Derivatives Using The Partial Least Squares Method, Tatjana Djakovic-Sekulic, Costel Sarbu, Nada Perisic-Janjic, Zagorka Lozanov-Crvenkovic
Quantitative Structure--Retention Study Of Some 2,4-Dioksotetrahydro- 1,3--Thiazole Derivatives Using The Partial Least Squares Method, Tatjana Djakovic-Sekulic, Costel Sarbu, Nada Perisic-Janjic, Zagorka Lozanov-Crvenkovic
Turkish Journal of Chemistry
Thin-layer chromatography on rice starch support and aqueous ammonia--organic modifier (methanol, dioxane, and acetone) mobile phases was used to study the effect on retention of the chromatographic system and the physicochemical properties of twelve 2,4-dioxotetrahydro-1,3-thiazoles. A multivariate approach to the retention behaviour of the investigated compounds with 3 quite different organic solvents was used to explain the interactions between the 1,3-thiazoles and the mobile phases. Partial least-squares (PLS) regression was used to quantify differences between the observed data and recognize the molecular properties with the greatest effect on retention for each modifier. Good correlation was obtained between experimental and calculated …
The Effect Of Electrocatalytic Activity And Crystal Structure Of Pbo_2 Surfaces On Polyphenylene Oxide (Ppo) Production In Acetonitrile, Serdar Abaci, Atti̇la Yildiz
The Effect Of Electrocatalytic Activity And Crystal Structure Of Pbo_2 Surfaces On Polyphenylene Oxide (Ppo) Production In Acetonitrile, Serdar Abaci, Atti̇la Yildiz
Turkish Journal of Chemistry
The crystallographic nature of PbO_2 films was changed by optimizing the electrolysis conditions in an electrodeposition solution of PbO_2. These PbO_2 films were then used to prepare PPO films. It was determined that \alpha and \beta modifications, and relative degrees of crystallinity had profound effects on the electrocatalytic performance of PbO_2 films in the production PPO films.
Voltammetric Determination Of Ascorbic Acid And Dopamine Simultaneously At A Single Crystal Au(111) Electrode, Zekerya Dursun, Levent Peli̇t, Isao Taniguchi
Voltammetric Determination Of Ascorbic Acid And Dopamine Simultaneously At A Single Crystal Au(111) Electrode, Zekerya Dursun, Levent Peli̇t, Isao Taniguchi
Turkish Journal of Chemistry
A single-crystal Au(111) electrode was used for the simultaneous determination of dopamine (DA) and ascorbic acid (AA) in a phosphate buffer solution at pH 6.9. The single-crystal Au(111) electrode displayed excellent electrocatalytic activity for DA and AA oxidation in comparison to a Au disk electrode. Although the anodic peaks of both reagents overlapped on the Au disk electrode, the anodic peak potentials of DA and AA in their mixture were well separated since the peak potential of AA was shifted to more negative values by cyclic and differential pulse voltammetry. The oxidation peak current increased linearly with the concentration of …
Water-Gas Shift Reaction Over Bimetallic Pt-Ni/Al_2o_3 Catalysts, Burcu Selen Çağlayan, Ahmet Erhan Aksoylu
Water-Gas Shift Reaction Over Bimetallic Pt-Ni/Al_2o_3 Catalysts, Burcu Selen Çağlayan, Ahmet Erhan Aksoylu
Turkish Journal of Chemistry
The water-gas shift (WGS) activity of bimetallic Pt-Ni/Al_2O_3 catalysts was investigated in the temperature range 200-450 °C using an idealized feed composition consisting of 3% CO and 6%-10% H_2O. The effects of the Ni content, space velocity, and H_2O/CO ratio on the catalytic performance of the catalysts were studied. An increase in the Ni content and H_2O/CO ratio shifted the carbon monoxide conversion--temperature curve toward lower reaction temperatures. No detectable methane formation was observed in the catalytic reaction tests. The results indicate that Pt-Ni/Al_2O_3 catalysts are highly selective and active for water-gas shift reactions under idealized conditions.
Synthesis Of 5-Arylamino-1h (2h)-Tetrazoles And 5-Amino-1-Aryl-1h-Tetrazoles From Secondary Arylcyanamides In Glacial Acetic Acid: A Simple And Efficient Method, Ali Reza Modarresi-Alam, Mahmoud Nasrollahzadeh
Synthesis Of 5-Arylamino-1h (2h)-Tetrazoles And 5-Amino-1-Aryl-1h-Tetrazoles From Secondary Arylcyanamides In Glacial Acetic Acid: A Simple And Efficient Method, Ali Reza Modarresi-Alam, Mahmoud Nasrollahzadeh
Turkish Journal of Chemistry
A simple and efficient method for the preparation of 5-arylamino-1H (2H)-tetrazoles (3a-i) and 5-amino-1-ary-1H-tetrazoles (4a-i), with excellent yields and high purity, from secondary arylcyanamides (1a-i) at room temperature in glacial acetic acid is described. Tautomers 3a-i were separated from tautomers 4a-i by crystallization in ethanol. A mechanism was introduced in glacial acetic acid. The ratio of isomers is described based on the electronic and steric effects of various substituents. The electron withdrawing group (-NO_2) increased the ratio of 4:3. The rate of product formation was enhanced by introducing electron donating substituents. ^1H-NMR and ^{13}C-NMR chemical shifts and multiplicities are also …
Development Of Alumina Supported Alkaline Catalysts Used For Biodiesel Production, Oğuzhan İlgen, Ayşe Ni̇lgün Akin
Development Of Alumina Supported Alkaline Catalysts Used For Biodiesel Production, Oğuzhan İlgen, Ayşe Ni̇lgün Akin
Turkish Journal of Chemistry
The transesterification of canola oil with methanol was studied in a heterogeneous system, using \gamma-Al_2O_3 supported alkaline catalysts. All the catalysts were prepared by incipient-wetness impregnation of an aqueous solution of alkaline compounds on \gamma-Al_2O_3 support. The effects of alkaline compound, methanol/canola oil molar ratio, reaction temperature, catalyst amount, and reaction time in biodiesel production were investigated. The catalyst with KOH loaded on \gamma-Al_2O_3 gave the highest basicity and the best catalytic activity for this reaction. The highest FAME yield obtained was 89.40%.
Synthesis And Biological Activity Of 4-(4-Hydroxybenzylidene)-2- (Substituted Styryl) Oxazol-5-Ones And Their O-Glucosides, Vijay Taile, Kishor Hatzade, Pravin Gaidhane, Vishwas Ingle
Synthesis And Biological Activity Of 4-(4-Hydroxybenzylidene)-2- (Substituted Styryl) Oxazol-5-Ones And Their O-Glucosides, Vijay Taile, Kishor Hatzade, Pravin Gaidhane, Vishwas Ingle
Turkish Journal of Chemistry
The 4-(4-hydroxybenzylidene)-2-methyl oxazol-5-ones 1 were treated with various aldehydes in the presence of acetic acid to form 4-(4-hydroxybenzylidene)-2-(substituted styryl) oxazol-5-ones 2a-i, which were glucosylated using \alpha-acetobromoglucose as a glucosyl donor to afford 4-(4-o-\beta-d-tetra-o-acetyl-glucoxybenzylidene)-2- (substituted styryl) oxazol-5-ones 3a-i, which were deacetylated using zinc acetate in absolute methanol to form 4-(4-o-\beta-d-glucoxybenzylidene)- 2-(substituted styryl) oxazol-5-ones 4a-i. The compounds showed good antimicrobial and antifungal activity.
Synthesis, Characterization, And Antibacterial Effect Of 4-Methoxy-2-(5-H/Me/Cl/No_2-1h-Benzimidazol-2-Yl)- Phenols And Some Transition Metal Complexes, Aydin Tavman, Serkan İki̇z, Arzu Funda Bağcigi̇l, N. Yakut Özgür, Seyyal Ak
Synthesis, Characterization, And Antibacterial Effect Of 4-Methoxy-2-(5-H/Me/Cl/No_2-1h-Benzimidazol-2-Yl)- Phenols And Some Transition Metal Complexes, Aydin Tavman, Serkan İki̇z, Arzu Funda Bağcigi̇l, N. Yakut Özgür, Seyyal Ak
Turkish Journal of Chemistry
4-Methoxy-2-(5-H/methyl/chloro/nitro-1H-benzimidazol-2-yl)-phenol(HL_X; X=1-4) ligands and HL_1 complexes with Fe(NO_3)_3, Cu(NO_3)_2, AgNO_3, and Zn(NO_3)_2 were synthesized and characterized. The structures of the compounds were confirmed on the basis of elemental analysis, molar conductivity, magnetic moment, FT-IR, UV-visible, and ^1H- and ^{13}C-NMR. Antibacterial activity of the free ligands, their hydrochloride salts, and the complexes was evaluated using the disk diffusion method in dimethyl sulfoxide (DMSO) as well as the minimum inhibitory concentration (MIC) dilution method, against 9 bacteria, and the results were compared with penicillin-G and oxytetracycline. It was observed that HL_1, [Ag(HL_1)](NO_3), and [Cu(L_1)_2](H_2O)_2 are effective on S. epidermidis, S. aureus, and …
Methanol Dehydration Reaction To Produce Clean Diesel Alternative Dimethylether Over Mesoporous Aluminosilicate-Based Catalysts, Di̇lek Varişli, Kenan Cem Tokay, Ayşegül Çi̇ftçi̇, Ti̇mur Doğu, Gülsen Doğu
Methanol Dehydration Reaction To Produce Clean Diesel Alternative Dimethylether Over Mesoporous Aluminosilicate-Based Catalysts, Di̇lek Varişli, Kenan Cem Tokay, Ayşegül Çi̇ftçi̇, Ti̇mur Doğu, Gülsen Doğu
Turkish Journal of Chemistry
Due to its good burning characteristics and high cetane number, dimethylether (DME) is considered as a highly attractive and clean alternative to diesel fuel. This ether can be produced by methanol dehydration reaction over solid acid catalysts. In the present study, activities of mesoporous aluminosilicate catalysts prepared by the hydrothermal synthesis route and containing Al/Si atomic ratios ranging between 0.03 and 0.18 were tested in methanol dehydration. The optimum Al/Si ratio was 0.09 for DME synthesis. Activity of silicotungstic acid (STA) impregnated aluminosilicate was also tested. This STA impregnated catalyst showed very high DME yield values at temperatures as low …
H_2{So}_4-Silica As An Efficient And Chemoselective Catalyst For The Synthesis Of Acylal From Aldehydes Under Solvent-Free Conditions, Seied Ali Pourmousavi, Zahra Zinati
H_2{So}_4-Silica As An Efficient And Chemoselective Catalyst For The Synthesis Of Acylal From Aldehydes Under Solvent-Free Conditions, Seied Ali Pourmousavi, Zahra Zinati
Turkish Journal of Chemistry
A variety of aldehydes react with acetic anhydride in the presence of a catalytic amount of H_2SO_4-silica to afford the corresponding 1,1-diacetates (acylals) in excellent yields. Ketones are not affected under the reaction conditions. The advantages are the simplicity of the acylation procedure, and the relatively non-toxic nature of the catalyst as well as its easy availability and low cost.
Synthesis, Characterization, And Optical Properties Of Novel 2,5-Bis[4-(2-(-Arylvinyl)Phenyl]-1,3,4-Oxadiazoles, Dao-Hang He, Yong-Chuang Zhu, Zhuo-Ru Yang, Ai-Xi Hu, Gao Cao
Synthesis, Characterization, And Optical Properties Of Novel 2,5-Bis[4-(2-(-Arylvinyl)Phenyl]-1,3,4-Oxadiazoles, Dao-Hang He, Yong-Chuang Zhu, Zhuo-Ru Yang, Ai-Xi Hu, Gao Cao
Turkish Journal of Chemistry
Six novel 2,5-bis[4-(2-arylvinyl)phenyl]-1,3,4-oxadiazoles were synthesized by introducing 1,3,4-oxadiazole moiety into the stilbene skeleton. The synthesis route included the cyclization of p-toluic acid and hydrazine hydrate catalyzed by polyphosphoric acid (PPA), bromination of 1,3-dibromo-5,5-dimethylhydantoin (DBDMH), esterification, and the Wittig-Horner reaction. All the title compounds were characterized by ^1H-NMR, MS, and elemental analysis. UV-Vis absorption and fluorescence emission spectra in THF solution were investigated; the compounds may have potential for use in organic optical materials.
Characterization And Electrochemical Study Of Nano-Composition Based Methylene Blue- And Riboflavin-Nafion On The Surface Of Gold Electrode, Saeed Rezaei-Zarchi, Aisha Javed, Hossein Mirjalili, Hossain Bari Abarghouei, Seyed Ali Hashemizadeh
Characterization And Electrochemical Study Of Nano-Composition Based Methylene Blue- And Riboflavin-Nafion On The Surface Of Gold Electrode, Saeed Rezaei-Zarchi, Aisha Javed, Hossein Mirjalili, Hossain Bari Abarghouei, Seyed Ali Hashemizadeh
Turkish Journal of Chemistry
A functional membrane, composed of the nanoparticles of methylene blue (MB) and Nafion, was constructed during the present study. The materials were characterized by the methods of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV-Visible and FT-IR. The average diameter of new nano-particles was estimated to be about 60 nm. A novel Nafion-riboflavin membrane was also constructed and characterized by the methods of SEM, TEM and UV-Visible spectroscopy. The estimated average diameter of the new nanoparticles was about 60 nm. The functional membranes of Nafion-riboflavin and Nafion-methylene blue showed a quasi-reversible electrochemical behavior, on the gold electrode, with …