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Articles 7291 - 7320 of 10319
Full-Text Articles in Physical Sciences and Mathematics
Preparation And Characterization Of Anticancer Drug-Loaded Implantable Plga Microparticles, Meltem Çeti̇n, İmran Vural, Alptuğ Ati̇la, Yücel Kadioğlu
Preparation And Characterization Of Anticancer Drug-Loaded Implantable Plga Microparticles, Meltem Çeti̇n, İmran Vural, Alptuğ Ati̇la, Yücel Kadioğlu
Turkish Journal of Chemistry
This article describes the preparation and characterization of anticancer drug-loaded poly(lactide-co-glycolide) (PLGA) microparticles. PLGA microparticles loaded with doxorubicin HCl (DOX) were prepared via o/w emulsion solvent evaporation. The release characteristics, encapsulation efficiency, size, and morphology of the PLGA microparticles were also determined. A cytotoxicity test was performed by using Glioma RG2 cancer cells to investigate the cytotoxicity of DOX-loaded PLGA microparticles. The DOX-loaded PLGA microparticles had an average diameter of 500 \pm 9 nm. The DOX encapsulation efficiency and drug loading were 22.75% and 0.78%, respectively. DOX-loaded PLGA microparticles displayed a significant cytotoxicity toward the RG2 cells as compared to …
Heterocyclic Synthesis Using Nitrilimines: Part 14. Synthesis Of New Pyrazole Derivatives, Hany Dalloul
Heterocyclic Synthesis Using Nitrilimines: Part 14. Synthesis Of New Pyrazole Derivatives, Hany Dalloul
Turkish Journal of Chemistry
A new series of 1,3,4,5-tetrasubstituted pyrazoles have been synthesized by the 1,3-dipolar cycloaddition of suitable nitrilimines to 3-propylidene and 3-benzylidene-phthalide. Both analytical and spectroscopic data of all the synthesized compounds are in full agreement with the proposed structures.
Surfactant-Controlled Aqueous Synthesis Of Sno_2 Nanoparticles Via The Hydrothermal And Conventional Heating Methods, Muhammad Akhyar Farrukh, Heng Boon Teck, Rohana Adnan
Surfactant-Controlled Aqueous Synthesis Of Sno_2 Nanoparticles Via The Hydrothermal And Conventional Heating Methods, Muhammad Akhyar Farrukh, Heng Boon Teck, Rohana Adnan
Turkish Journal of Chemistry
Tin oxide nanoplates and nanoballs were fabricated using a cationic surfactant of cetyltrimethylammonium bromide (CTABr) as an organic supramolecular template and tin(IV) chloride as an inorganic precursor via the hydrothermal and conventional heating methods. Urea, which decomposes to ammonium and hydroxide ions during hydrolysis, was used as the source of slow homogeneous precipitation of Sn^{4+} with OH^- to control the particle size. The influence of different reaction parameters (time, temperature, and ratio of Sn^{4+} to CTABr) on particle sizes, particle distribution, and morphology was investigated using X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) spectroscopy. XRD …
Synthesis And Characterization Of Novel Triazol Compounds Containing A Thiophen Ring As Potential Antifungal Agents And The Structure Of 2-(2-Hydroxy-2-P-Tolyethyl)-5-(Thiophen-2-Ylmethyl)- 4-(4h-1,2,4-Triazol-4-Yl)-2h-1,2,4-Triazol-3(4h)-One, Yasemi̇n Ünver, Esra Düğdü, Kemal Sancak, Mustafa Er, Reşat Ustabaş
Synthesis And Characterization Of Novel Triazol Compounds Containing A Thiophen Ring As Potential Antifungal Agents And The Structure Of 2-(2-Hydroxy-2-P-Tolyethyl)-5-(Thiophen-2-Ylmethyl)- 4-(4h-1,2,4-Triazol-4-Yl)-2h-1,2,4-Triazol-3(4h)-One, Yasemi̇n Ünver, Esra Düğdü, Kemal Sancak, Mustafa Er, Reşat Ustabaş
Turkish Journal of Chemistry
A series of new 4-(3,5-disubstitue-4H-1,2,4-triazol-4-yl)- 5-(thiophen-2-yl-methyl)-2H-1,2,4-triazol-3(4H)-ones (3a-c) were obtained by reaction N'-1-ethoxy-2-thiophen-2-yl-ethylydene hydrazino carboxylic acid ethyl ester (1) and 4-amino-4H-1,2,4-triazoles (2). 4-(3,5-disubstitue-4H-1,2,4-triazol-4-yl)-2-(2-oxo-2-arylethyl)-5- (thiophen-2-yl-methyl)-2H-1,2,4-triazol-3(4H)-ones (4a-e) and ethyl 2-(4-(3,5-disubstitue-4H-1,2,4-triazol-4-yl)-5-oxo-3-(thiophen-2-ylmethyl)- 4,5-dihydro-1,2,4-triazol-1-yl)acetates (6a-c) were obtained by reaction of compounds 3 and bromoacetophenon derivatives and bromo ethylacetate, respectively. Compounds 5a-e were synthesized from the reaction of corresponding compounds 4a-e with NaBH_4. Compounds 7a-c were obtained by the reaction compounds 6 and LiAlH_4. Seventeen new compounds were synthesized and characterized by elemental analyses, IR, ^1H-NMR, and ^{13}C-NMR spectral data. The structure of compound 5d was inferred through IR, ^1H-, ^{13}C-NMR, elemental analyses, and X-ray spectral techniques. …
Silica Supported Polyphosphoric Acid (Ppa-Sio_2): An Efficient And Reusable Heterogeneous Catalyst For The One-Pot Synthesis Of \Alpha -Amino Phosphonates, Malek Taher Maghsoodlou, Sayyed Mostafa Habibi-Khorassani, Reza Heydari, Nourollah Hazeri, Seyed Sajad Sajadikhah, Mohsen Rostamizadeh, Leila Keishams
Silica Supported Polyphosphoric Acid (Ppa-Sio_2): An Efficient And Reusable Heterogeneous Catalyst For The One-Pot Synthesis Of \Alpha -Amino Phosphonates, Malek Taher Maghsoodlou, Sayyed Mostafa Habibi-Khorassani, Reza Heydari, Nourollah Hazeri, Seyed Sajad Sajadikhah, Mohsen Rostamizadeh, Leila Keishams
Turkish Journal of Chemistry
An efficient green protocol is described for the preparation of \alpha -amino phosphonates, employing a one-pot three-component condensation reaction between aldehydes, amines, and trialkyl phosphites in the presence of PPA-SiO_2 under solvent-free conditions at 80 °C. The present procedure offer advantages such as high to excellent yields, short reaction time, inexpensiveness, recovery, and reusability of catalyst.
A New Dinuclear Lead(Ii) Complex Of 2,3-Diphenyl-Tetrazole-5-Thione: Synthesis And Characterization, Ruirui Zhuang, Fangfang Jian, Kefei Wang
A New Dinuclear Lead(Ii) Complex Of 2,3-Diphenyl-Tetrazole-5-Thione: Synthesis And Characterization, Ruirui Zhuang, Fangfang Jian, Kefei Wang
Turkish Journal of Chemistry
The present work reports on the synthesis, crystal structure, fluorescence, electrochemical behavior, and thermogravimetric analysis of a new dinuclear lead(II) complex of 2,3-diphenyl-tetrazole-5-thione. Its structure was characterized by X-ray crystallography, IR spectroscopy, and elemental analysis. Each lead atom adopts a distorted octahedral geometry by coordinating to 2 sulfur atoms from 2 2,3-diphenyl-tetrazole-5-thione ligands and 4 oxygen atoms from 3 nitrates. The fluorescence spectrum shows that the title complex has 2 fluorescence emission peaks, at 412 nm and 433 nm. Cyclic voltammetry studies show that the title complex has only one reduction peak, at 0.309 V. The thermogravimetric analysis indicates that …
Synthesis And Characterisation Of Vanadium(Iii) Complexes Of Biphenylphenols, Neeraj Sharma, Maridula Thakur, S C. Chaudhry
Synthesis And Characterisation Of Vanadium(Iii) Complexes Of Biphenylphenols, Neeraj Sharma, Maridula Thakur, S C. Chaudhry
Turkish Journal of Chemistry
The vanadium(III) complexes of composition [VCl_{3-n}(OAr^{1,2})_n.(THF)_2] (OAr^1 = 2-phenylphenoxo and OAr^2 = 4-phenylphenoxo, THF = tetrahydrofuran; n = 1 /to 3) were prepared by in situ reaction of VCl_3.(THF)_3 with sodium salt of respective phenols in tetrahydrofuran. The complexes were characterised by elemental analysis, molar conductance, FTIR, UV-Vis, and FAB-mass spectral and magnetic studies. The thermal behaviour of some of the complexes was studied by TG-DTA. The dinuclear phenoxy bridged octahedral structures for the complexes were inferred from the spectral and magnetic studies.
A Simple And Efficient Procedure For Synthesis Of Optically Active 1,3,4-Oxadiazole Derivatives Containing L-Amino Acid Moieties, Naser Foroughifar, Akbar Mobinikhaledi, Sattar Ebrahimi
A Simple And Efficient Procedure For Synthesis Of Optically Active 1,3,4-Oxadiazole Derivatives Containing L-Amino Acid Moieties, Naser Foroughifar, Akbar Mobinikhaledi, Sattar Ebrahimi
Turkish Journal of Chemistry
Some new unsymmetrical and optically active 2,5-disubstituted 1,3,4-oxadiazoles 5a-j were efficiently synthesized by cyclization reaction of diacylhydrazides 4a-j. The synthesis of the title compounds was achieved by the reaction of acyl hydrazides 3a-b and N-phetaloyl-L-amino acids 1a-e in the presence of the phosphoroxy chloride (POCl_3) as an anhydrous reagent.
A Calorimetric Study Of The Interaction Of Silver Ions With Jack Bean Urease, Ali Akbar Saboury, Elahe Poorakbar, Gholamreza Rezaei-Behbehani
A Calorimetric Study Of The Interaction Of Silver Ions With Jack Bean Urease, Ali Akbar Saboury, Elahe Poorakbar, Gholamreza Rezaei-Behbehani
Turkish Journal of Chemistry
A thermodynamic study of silver ions by jack bean urease (JBU) was carried out at 2 temperatures, 27 and 37 °C, in Tris buffer (30 mM; pH 7.0) using isothermal titration calorimetry (ITC). There was a set of 12 identical and noninteracting binding sites for the silver ions. The intrinsic dissociation equilibrium constant and the molar enthalpy of binding were 185 \mu M and -16.7 kJ mol^{-1} at 27 °C, and 229 \mu M and -16.3 kJ mol^{-1} at 37 °C, respectively. The molar entropy of binding was +15.7 J K^{-1} mol^{-1} at 27 °C and +17.1 J K^{-1} mol^{-1} …
Synthesis And Characterization Of Gold Nanoparticles Supported On Zinc Oxide Via The Deposition-Precipitation Method, Hanani Yazid, Rohana Adnan, Shafida Abdul Hamid, Muhammad Akhyar Farrukh
Synthesis And Characterization Of Gold Nanoparticles Supported On Zinc Oxide Via The Deposition-Precipitation Method, Hanani Yazid, Rohana Adnan, Shafida Abdul Hamid, Muhammad Akhyar Farrukh
Turkish Journal of Chemistry
Gold nanoparticles supported on zinc oxide nanoparticles were synthesized at several pH levels via the deposition-precipitation (DP) method. The effects of pH on gold loading, particle size, and particle size distribution on the support were studied at the iso-electric point (IEP) as well as below and above the IEP of ZnO. The addition of the support significantly changed the pH of the solution. The effects of adjusting the pH before and after the addition of the support into the gold chloride solution were also investigated. Gold particles with diameters of less than 5 nm were obtained. The results revealed that …
Co(Iii) Catalysed Asymmetric Ring-Opening Of Epichlorohydrin By Salicylaldehyde Derivatives: Reversal Of Enantioselectivity And Rate Acceleration On Addition Of Alcl_3, Leman Karadeni̇z, Gamze Koz, Kadri̇ye Aydin, Stephen Thomas Astley
Co(Iii) Catalysed Asymmetric Ring-Opening Of Epichlorohydrin By Salicylaldehyde Derivatives: Reversal Of Enantioselectivity And Rate Acceleration On Addition Of Alcl_3, Leman Karadeni̇z, Gamze Koz, Kadri̇ye Aydin, Stephen Thomas Astley
Turkish Journal of Chemistry
Using asymmetric Cobalt(III) salen catalysts, the ring-opening of epichlorohydrin by 2,3-dihydroxybenzal- dehyde and 2,4- dihydroxybenzaldehyde was found to occur at the phenolic groups most distant from the aldehydic group. Switching catalysts afforded a reversal in enantioselectivity. For 2,3-dihydroxybenzaldehyde and salicylaldehyde, addition of AlCl_3 to the reaction mixture led to an increase in reaction rate without any decrease in product enantiopurity.
A Novel Optical Membrane With Extended Detection Range Of Ph, Meissam Noroozifar, Mozhgan Khorasani Motlagh, Safeyeh Bahmanzadeh, Shokoofah Boroon
A Novel Optical Membrane With Extended Detection Range Of Ph, Meissam Noroozifar, Mozhgan Khorasani Motlagh, Safeyeh Bahmanzadeh, Shokoofah Boroon
Turkish Journal of Chemistry
A pH optical sensor was developed based on the use of a mixture of Malachite Green Oxalate and Bromocresol Green indicators immobilized in a triacetylcellulose membrane, which had been previously hydrolyzed. Requirements of the pH indicators were investigated, including the effects of the coupling pH, indicator ratio, and concentrations of the indicators. The pH sensor performed with a very fast response (10 s) and long term stability with no significant leaching of the dyes. The sensor had a linear response over a range of 6.6 pH units in the pH range between 0.4 and 7.0. A relative standard deviation of …
Convenient Synthesis And Anion Recognition Property Of Acylhydrazone-Based Molecular Tweezer Receptors, Hai-Xian Ren, Ming-Gen Zhao, Ying-Jin Wang
Convenient Synthesis And Anion Recognition Property Of Acylhydrazone-Based Molecular Tweezer Receptors, Hai-Xian Ren, Ming-Gen Zhao, Ying-Jin Wang
Turkish Journal of Chemistry
Three acylhydrazone-based compounds were designed as novel neutral sensors for anions, and synthesized by simple steps in good yields. Their anion recognition properties were studied by UV-vis and ^1H-NMR spectroscopy. The results showed that the receptors 1, 2, and 3 all had a better selectivity for F^- and CH_3COO^-, but no evident binding with Cl^-, Br^-, I^-, NO_3^-, H_2PO_{4}^-, or HSO_{4}^-. The results indicated that anion recognition was achieved via convergent hydrogen bond interactions from acylhydrazone functionality on the side arms. The UV-vis data indicated that a 1:1 stoichiometry complex was formed between compounds 1, 2, or 3 and anions. …
Synthesis And Super-Swelling Behavior Of A Novel Low Salt-Sensitive Protein-Based Superabsorbent Hydrogel: Collagen-G-Poly(Amps), Mohammad Sadeghi, Hossein Hosseinzadeh
Synthesis And Super-Swelling Behavior Of A Novel Low Salt-Sensitive Protein-Based Superabsorbent Hydrogel: Collagen-G-Poly(Amps), Mohammad Sadeghi, Hossein Hosseinzadeh
Turkish Journal of Chemistry
Superabsorbent polymers are obtained by the graft copolymerization of 2-acrylamido-2-methylpropanesul- fonic acid (AMPS) monomer onto collagen, using ammonium persulfate as a free radical initiator in the presence of methylene bisacrylamide as a crosslinker. Infrared spectroscopy and TGA thermal analysis were carried out to confirm the chemical structure of the hydrogel. Moreover, morphology of the samples was examined by scanning electron microscopy (SEM). The effect of reaction variables on swelling capacity was investigated to achieve a hydrogel with improved water absorbency. Under the optimized conditions concluded, maximum capacity of swelling in distilled water was found to be 268 g/g. The swelling …
Bromodimethylsulfonium Bromide/Tetrabutylammonium Nitrite: An Efficient Catalyst Mixture For The Nitration Of Phenols, Batool Akhlaghinia, Ali Reza Pourali
Bromodimethylsulfonium Bromide/Tetrabutylammonium Nitrite: An Efficient Catalyst Mixture For The Nitration Of Phenols, Batool Akhlaghinia, Ali Reza Pourali
Turkish Journal of Chemistry
Nitrophenols were obtained via direct nitration of phenols with tetrabutylammonium nitrite in the presence of bromodimethylsulfonium bromide at room temperature in high yields under aprotic conditions.
Synthesis And Characterisations Of Some New 2,4-Dihydro-[1,2,4]- Triazol-3-One Derivatives And X-Ray Crystal Structures Of 4-(3-Phenylallylideneamino)-5-Thiophen-2-Yl-Methyl-2,4-Dihydro-[1,2,4]Triazol-3-One, Kemal Sancak, Yasemi̇n Ünver, Canan Kazak, Esra Düğdü, Burcu Arslan
Synthesis And Characterisations Of Some New 2,4-Dihydro-[1,2,4]- Triazol-3-One Derivatives And X-Ray Crystal Structures Of 4-(3-Phenylallylideneamino)-5-Thiophen-2-Yl-Methyl-2,4-Dihydro-[1,2,4]Triazol-3-One, Kemal Sancak, Yasemi̇n Ünver, Canan Kazak, Esra Düğdü, Burcu Arslan
Turkish Journal of Chemistry
Compounds 2 were synthesised via the reaction of 4-amino-5-thiophen-2-yl-methyl-2,4-dihydro-[1,2,4]-triazol-3-one (1) with aldehydes. Compounds 3 and 4 were obtained from compounds 2 with bromo acetophenone and ethyl bromoacetate, respectively. The synthesis of compounds 2, 3, and 4 and crystal structure of compound 2a are being reported. The molecular structures were identified by IR, ^1H-NMR, ^{13}C-NMR, MS, and elemental analyses. Compound 2a crystallises in the monoclinic P 2_1/n space group, with a = 6.565(5) Å, b = 18.278(5) Å, c = 13.8166(18) Å, \beta = 96.227(5)°, V = 1553.6(14) Å^3, Z = 4. The newly compounds synthesised were screened for their antibacterial …
Synthesis And Crystal Structure Of A Novel Multimodal Ligand, 6,6'-Bis(2-(Di(Pyridin-2-Yl)Methylene)-1-Methylhydrazinyl)-2,2'-Bipyridine, And Its Copper(I) Complex, {[Cu_3l_2](Pf_6)_3° 3h_2o} (1), Çağlar Ağaç, İsmai̇l Yilmaz, Abdurrahman Şengül, Simon J. Coles
Synthesis And Crystal Structure Of A Novel Multimodal Ligand, 6,6'-Bis(2-(Di(Pyridin-2-Yl)Methylene)-1-Methylhydrazinyl)-2,2'-Bipyridine, And Its Copper(I) Complex, {[Cu_3l_2](Pf_6)_3° 3h_2o} (1), Çağlar Ağaç, İsmai̇l Yilmaz, Abdurrahman Şengül, Simon J. Coles
Turkish Journal of Chemistry
The single crystal X-ray structure of the novel multimodal ligand 6,6'-bis(2-(di(pyridin-2-yl)methylene)-1-methylhydrazinyl)-2,2'-bipyridine, C_{34}H_{28}N_{10} (L), was determined at 120 (2) K. The ligand possesses a centre of symmetry that generates a planar bipyridyl core with the hydrazone substituents in a trans-geometry. The di-2-pyridyl moieties at either terminus of the molecule twist out of the plane (52.90 and 56.32 Å). The crystal structure comprises 2-dimensional ribbons that stack about each other so as to optimise van der Waals interactions and packing efficiency. Studies of the coordination properties of the novel multimodal ligand with copper(I) show that 2 ligand strands wrapped around the copper(I) …
Effect Of Various Substituents On Intramolecular 1,1-Vinylboration, Synthesis Of 1-Silacyclobutene Derivatives, Ezzat Khan, Bernd Wrackmeyer
Effect Of Various Substituents On Intramolecular 1,1-Vinylboration, Synthesis Of 1-Silacyclobutene Derivatives, Ezzat Khan, Bernd Wrackmeyer
Turkish Journal of Chemistry
The reaction of 1-boryl-1-alkenyl chlorosilane derivatives with alkynyllithium reagents [Li-C\equiv C-R^3 (R^3~=~Ph, SiMe_3)] at low temperature (--78 °C) affords alkenyl(alkyn-1-yl)silanes. These compounds are precursors of 1-silacyclobutene derivatives, which are formed via intramolecular 1,1-vinylboration. This reaction works for various groups at silicon (R^1/R^2: R^1 = H, Me, Ph; R^2 = Me, Ph) and at the C=C and C\equiv C units (R/R^3: R = ^nBu, Ph; R^3 = ^nBu, Ph, SiMe_3). The conversion into 1-silacyclobutene derivatives is incomplete only in the case of R^3 = SiMe_3. The reactions were monitored by NMR spectroscopy in order to elucidate the reaction mechanism, and the …
Electrochemical Impedance Spectroscopic Studies Of The Passive Layer On The Surface Of Copper As A Function Of Potential, Amtul Naseer, Athar Khan
Electrochemical Impedance Spectroscopic Studies Of The Passive Layer On The Surface Of Copper As A Function Of Potential, Amtul Naseer, Athar Khan
Turkish Journal of Chemistry
Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) were used to investigate the oxide layer formed on a copper disc electrode and the changes that took place when treated potentiostatically in the range of -0.3 V to 0.9 V in buffer of pH 8.5. The response of an electrode using EIS, initially at equilibrium, to an applied potential was then modeled with equivalent circuits, proposed for different potential regions that completely illustrated the Cu/oxide/electrolyte systems and their properties in terms of 2 interfaces. Criterion for the applicability of equivalent circuit models was discussed. Changes in the film/metal interface as a …
Chemical Composition And Antimicrobial Activity Of The Essential Oils Of Mosses (Tortula Muralis Hedw., Homalothecium Lutescens (Hedw.) H. Rob., Hypnum Cupressiforme Hedw., And Pohlia Nutans (Hedw.) Lindb.) From Turkey, Osman Üçüncü, Tayyi̇be Beyza Cansu, Turan Özdemi̇r, Şengül Alpay Karaoğlu, Nuretti̇n Yayli
Chemical Composition And Antimicrobial Activity Of The Essential Oils Of Mosses (Tortula Muralis Hedw., Homalothecium Lutescens (Hedw.) H. Rob., Hypnum Cupressiforme Hedw., And Pohlia Nutans (Hedw.) Lindb.) From Turkey, Osman Üçüncü, Tayyi̇be Beyza Cansu, Turan Özdemi̇r, Şengül Alpay Karaoğlu, Nuretti̇n Yayli
Turkish Journal of Chemistry
The essential oils of mosses [Tortula muralis Hedw. (Pottiaceae), Homalothecium lutescens (Hedw.) H. Rob. (Brachytheciaceae), Hypnum cupressiforme Hedw. (Hypnaceae), and Pohlia nutans (Hedw.) Lindb. (Mniaceae)] were investigated by means of GC-FID/MS techniques. The major components were nonanal (18.3%) and tetradecanol (4.3%) in the oil of T. muralis, nonanal (36.8%) and tricosane (6.5%) in the oil of H. lutescens, nonanal (12.5%) and 2E-tetradecen-1-ol (6.9%) in the oil of H. cupressiforme, and nonanal (7.8%) and 2E-tetradecen-1-ol (7.1%) in the oil of P. nutans. The essential oils of T. muralis, H. lutescens, H. cupressiforme, and P. nutans were rich as in non-terpenoid components …
Synthesis And Antimicrobial Activities Of Some New 1,2,4-Triazole Derivatives, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Hacer Bayrak, Hakan Bektaş, Şengül Alpay Karaoğlu
Synthesis And Antimicrobial Activities Of Some New 1,2,4-Triazole Derivatives, Nesli̇han Demi̇rbaş, Ahmet Demi̇rbaş, Hacer Bayrak, Hakan Bektaş, Şengül Alpay Karaoğlu
Turkish Journal of Chemistry
The synthesis of ethyl [3-(cyanomethyl)-5-alkyl-4H-1,2,4-triazol- 4-yl]carbamates (2a-d) was performed starting from ethyl 2-[ethoxy(4- (aryl)methylene]hydrazinecarboxylates (1a, 1b). The treatment of 2a with thiosemicarbazide afforded ethyl [3-[(5-amino-1,3,4-thiadiazol- 2-yl)methyl]-5-(4-nitrophenyl)-4H-1,2,4-triazol-4-yl]carbamates (3a), whereas compound 2b produced 5-{[4-amino-5-(4-methylphenyl)- 4H-1,2,4-triazol-3-yl]methyl}-1,3,4-thiadiazol-2-amine (3b) in the same reaction conditions. The treatment of tert-butyl 2-[2-(4-chlorophenyl)-1-ethoxyethylidene]hydrazinecarboxylate (5) with malonohydrazide or cyanoacethydrazide gave the corresponding 1,2,4-triazol-ylcarbamate derivatives (6 or 9); then the hydrolysis of these compounds resulted in the formation of 3-{[4-amino-5-(4- chlorobenzyl)-4H-1,2,4-triazol-3-yl]methyl}-5-(4-chlorobenzyl)-4H- 1,2,4-triazol-4-amine (7) and [4-amino-5-(4-chlorobenzyl)-4H- 1,2,4-triazole-3-yl]acetonitrile (10), respectively. The synthesis of the Schiff base derivatives 3-(4-chlorobenzyl)-5-{[5-(4-chloroben- zyl)-4-[(2-hydroxyphenyl-methylene)amino]-4H-1,2,4-triazol-3-yl]methyl} -N-(2-hydroxyphenylmethylene)-4H-1,2,4-triazol-4-amine (8), and (5-(4-chlorobenzyl)-4-{[(2,6-dichlorophenyl)methylene]amino}-4H-1,2,4- triazol-3-yl)acetonitrile (12) was performed from the reaction of compounds 7 …
Ethyl 5-Oxo-3-Arylamino-2,5-Dihydroisoxazole-4- Carboxylates As Sources Of Imidazopyrimidine And Aminoindole Derivatives, Ahmad Poursattar Marjani, Jabbar Khalafy
Ethyl 5-Oxo-3-Arylamino-2,5-Dihydroisoxazole-4- Carboxylates As Sources Of Imidazopyrimidine And Aminoindole Derivatives, Ahmad Poursattar Marjani, Jabbar Khalafy
Turkish Journal of Chemistry
The reaction of ethyl 5-oxo-3-arylamino-2,5-dihydroisoxazole-4- carboxylates with 2-chloropyrimidine and 2-chlorobenzoxazole gave the corresponding isoxazolones with pyrimidine and benzoxazole rings substituted on N-2. Their rearrangements with triethylamine in ethanol produced the corresponding imidazopyrimidine and aminoindole derivatives, respectively, through intramolecular cyclisation.
Reactions Of 4-Benzoyl-1,5-Diphenyl-1h-Pyrazole-3- Carboxylic Acid Chloride With Various Hydroxylamines And Carbazates, Eli̇f Korkusuz, İsmai̇l Yildirim
Reactions Of 4-Benzoyl-1,5-Diphenyl-1h-Pyrazole-3- Carboxylic Acid Chloride With Various Hydroxylamines And Carbazates, Eli̇f Korkusuz, İsmai̇l Yildirim
Turkish Journal of Chemistry
The 1H-pyrazole-3-carboxylic acid 2 was converted via reactions of its acid chloride 3 with various hydroxylamine 4a-f and carbazate derivatives 8a-c into the corresponding novel N-substituted-4-benzoyl-1,5-dipenyl-1H-pyrazole-3-carboxamides 5a-c, N,N-disubstituted-4-benzoyl-1,5-diphenyl-1H-pyrazole-3-carboxylates 6d,e, 4-benzoyl-N-{[(4-benzoyl-1,5-diphenyl-1H-pyrazol-3-yl)carbonyl]oxy}- N-methyl-1,5dip- henyl-1H-pyrazole-3-carboxamide (7), and 4-benzoyl-N'-(alkoxycarbonyl)-1,5-diphenyl-1H-pyrazole-3-car- bohydrazides 9a,b and 10, respectively, in good yields (65\%-90\%). The reactions of 3 with 4 and 8 in xylene for 8-15 h with catalytic amounts of base led to the formation of the products 5-7, 9, and 10. The structures of all new synthesized compounds were established by the ^{13}C-NMR, ^1H-NMR, IR spectroscopic data, and elemental analyses.
An Efficient And Green Approach For The Synthesis Of Vinyl Aryl Ethers In The Presence Of Guanidine Hydrochloride, Seyed Mohammad Vahdat, Robabeh Baharfar
An Efficient And Green Approach For The Synthesis Of Vinyl Aryl Ethers In The Presence Of Guanidine Hydrochloride, Seyed Mohammad Vahdat, Robabeh Baharfar
Turkish Journal of Chemistry
A stereoselective procedure for vinyl aryl ether bond formation by direct coupling of dialkyl acetylenedicarboxylates and substituted phenols or naphthols under mild reaction conditions has been developed. Using guanidine hydrochloride as a new catalyst and water-acetone as green solvent, dialkyl acetylenedicarboxylates were reacted with substituted phenols or naphthols in room temperature to produce vinyl aryl ethers in good to excellent yields.
Vapor Phase Alkylation Of Toluene Using Various Alcohols Over H3po4/Mcm-41 Catalyst: Influence Of Reaction Parameters On Vapor Phase Alkylation Of Toluene Using Various Alcohols Over H_3po_4/Mcm-41 Catalyst: Influence Of Reaction Parameters On Selectivity And Conversion, Alireza Abbaspourrad, Roozbeh Javadkalbasi, Farzad Zamani
Vapor Phase Alkylation Of Toluene Using Various Alcohols Over H3po4/Mcm-41 Catalyst: Influence Of Reaction Parameters On Vapor Phase Alkylation Of Toluene Using Various Alcohols Over H_3po_4/Mcm-41 Catalyst: Influence Of Reaction Parameters On Selectivity And Conversion, Alireza Abbaspourrad, Roozbeh Javadkalbasi, Farzad Zamani
Turkish Journal of Chemistry
A mesoporous MCM-41 molecular sieve material with a molar ratio of SiO_2/Al_2O_3 = 70 and loaded with H_3PO_4 was used as a catalyst for the alkylation of toluene, using various alcohols, namely methanol, iso-propanol, and tert-butanol, as alkylating agents. Para-alkylated toluene was the predominant product, formation of which was enhanced by moderate temperature, low amounts of the alkylating agents in the feed, and high carrier gas flow rate. Time on stream was found to exert a profound effect on the selectivity and conversion to the different products.
Synthesis And Surfactant Properties Of N-Acylation Compounds Derived From Hydrolysis Degradation Products Of N-(\Beta-Cianoethyl)-\Epsilon-Caprolactam, Andreea Bondarev
Synthesis And Surfactant Properties Of N-Acylation Compounds Derived From Hydrolysis Degradation Products Of N-(\Beta-Cianoethyl)-\Epsilon-Caprolactam, Andreea Bondarev
Turkish Journal of Chemistry
N-acyl amino acids can be used as active surface agents in the detergents industry, as well as in the pharmaceutical industry and cosmetics. Properties of these compounds are superior to those of fatty acids soaps and they are not toxic to the environment and have low Kraft points, because of peptide bonds (CO-NH). Acylation at the nitrogen atom can be performed with good yields without catalysts, for strong nucleophilic derivatives. The synthesis of some derivatives of 4-azasebacic acid, which are hydrolysis degradation products from N-(\beta -cianoethyl)-\epsilon -caprolactam, has been described and the N-acylation processes for these compounds are also presented. …
Nile Blue-Hexacyanoferrate Carbon Paste Modified Electrode As An Amperometric Sensor For Determination Of Hydrazine, Reza Sabzi, Elnaz Minaie, Khalil Farhadi, Mirmaqsoud Golzan
Nile Blue-Hexacyanoferrate Carbon Paste Modified Electrode As An Amperometric Sensor For Determination Of Hydrazine, Reza Sabzi, Elnaz Minaie, Khalil Farhadi, Mirmaqsoud Golzan
Turkish Journal of Chemistry
The main problem associated with metal hexacyanoferrates (MHCFs) is their instability at high pH values. We synthesized a new Prussian Blue analogue, Nile-Blue hexacyanoferrate (NBHCF), that remains stable in 0.2 M KOH. A carbon paste (CPE) chemically modified electrode (ME) containing NBHCF was prepared as a stable electrochemical sensor for measuring hydrazine. A detailed characterization of the electrochemical and electrocatalytic behavior of NBHCF was performed using cyclic voltammetric, chronoamperometric, differential pulse voltammetric (DPV) and hydrodynamic amperometric methods. The NBHCF-modified electrode produced reproducible redox peaks and resulted in a linear increase in the oxidation signal of hydrazine with increasing concentration of …
Determination Of Trace Element Contents Of Thymus Species From Turkey, Fatümetüzzehra Küçükbay, Ebru Kuyumcu
Determination Of Trace Element Contents Of Thymus Species From Turkey, Fatümetüzzehra Küçükbay, Ebru Kuyumcu
Turkish Journal of Chemistry
Eleven mineral and trace elements (Mg, Ca, K, Fe, Mn, Al, Zn, Cu, Cd, Ni, and Pb) were determined in the Thymus species growing in Turkey. The total concentrations were measured in samples mineralized with concentrated nitric acid and hydrogen peroxide in a microwave system. The determination of mineral and trace elements in the leaves of the Thymus species was carried out by flame and graphite furnace atomic absorption spectrometry. The accuracy of the method was ensured by using standard reference material (NIST-SRM 1515 apple leaves). The concentration of elements in the Thymus species and their biological activity on humans …
Synthesis And Characterization Of Ba/Mcm-41, Emi̇ne Kaya, Nuray Oktar, Gürkan Karakaş, Kirali̇ Mürtezaoğlu
Synthesis And Characterization Of Ba/Mcm-41, Emi̇ne Kaya, Nuray Oktar, Gürkan Karakaş, Kirali̇ Mürtezaoğlu
Turkish Journal of Chemistry
Mesoporous Ba/MCM-41 type materials (Ba/MCM-41) with high Ba/Si molar ratios between 0.025 and 0.1 were synthesized by direct hydrothermal synthesis. The samples were characterized by XRD, nitrogen adsorption, TGA-DTA, FTIR, SEM-EDS, and TEM techniques. BET surface areas of samples with various Ba loadings were found between 722 and 931 m^2/g with 28 Å average pore size, which is consistent with the pore size of 30 Å for pure MCM-41 samples synthesized by the same procedure. The crystal structures of synthesized MCM-41 and Ba/MCM-41 were confirmed by XRD analysis. Among the investigated Ba/MCM-41 samples, the formation of barium oxide and barium …
Computational Study On Nitronium Squarate - Potential Oxidizers For Solid Rocket Propulsion?, Eli̇f Gökçinar, Thomas Klapötke
Computational Study On Nitronium Squarate - Potential Oxidizers For Solid Rocket Propulsion?, Eli̇f Gökçinar, Thomas Klapötke
Turkish Journal of Chemistry
The enthalpies of formation for solid ionic nitronium squarate, [NO_2]_2[C_4O_4], and covalent squaric acid dinitrate ester, O_2N-C_4O_4-NO_2, were calculated using the complete basis set (CBS-4M) method of Petersson and coworkers in order to obtain very accurate energies. The covalent form (O_2N-C_4O_4-NO_2) was identified as the more stable isomer. The combustion parameters with respect to possible use as ingredients in solid rocket motors for both stable species were calculated using the EXPLO5 code. The performance of an aluminized formulation with covalently bound dinitrate ester (O_2N-C_4O_4-NO_2) was shown to be comparable to that of ammonium perchlorate/aluminum. This makes squaric acid dinitrate ester …