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Optimization Of Lifepo_4 Synthesis By Hydrothermal Method, Muhsi̇n Mazman, Ömür Çuhadar, Davut Uzun, Ercan Avci, Emre Bi̇çer, Tevhi̇t Cem Kaypmaz, Ümüt Kadi̇roğlu Jan 2014

Optimization Of Lifepo_4 Synthesis By Hydrothermal Method, Muhsi̇n Mazman, Ömür Çuhadar, Davut Uzun, Ercan Avci, Emre Bi̇çer, Tevhi̇t Cem Kaypmaz, Ümüt Kadi̇roğlu

Turkish Journal of Chemistry

Optimization of the LiFePO_4 cathode active material synthesis process in the hydrothermal method consists of many factors, including pH, carbon coating, particle size optimization, sintering and hydrothermal synthesis temperature. The main goal of this study is to determine the effect of particle size, pH and carbon coating on capacity and cycle performance. In this study, LiFePO_4 cathode active materials were prepared at different pH (6.5 and 8.5) and temperature (160 and 180 °C) levels using the hydrothermal method. The hydrothermal synthesis products were sintered at 400, 500, 600, and 700 °C with 5% and 7% carbon source. The initial discharge …


Crystal Growth Morphology Of Magnesium Hydroxide, Jiansong Wu, Juan Du, Yi-Min Gao Jan 2014

Crystal Growth Morphology Of Magnesium Hydroxide, Jiansong Wu, Juan Du, Yi-Min Gao

Turkish Journal of Chemistry

In this paper, the formation process of magnesium hydroxide unit cells, as well as the structural characteristics and growth morphology of magnesium hydroxide, is discussed from the perspective of growth units. The growth process of the hexagonal structure of the magnesium hydroxide is as follows: the growth units are first incorporated into a larger hexagonal dimension unit on the same plane, and then the hexagonal layers connect to each other in the z-axis direction for the hexagonal magnesium hydroxide unit cell. The results of the study show that the model of anion coordination polyhedron growth units may be reasonably deduced …


Partial Purification And Biochemical Characterization Of An Extremely Thermo- And Ph-Stable Esterase With Great Substrate Affinity, Esra Özbek, Yakup Kolcuoğlu, Leyla Konak, Ahmet Çolak, Fulya Öz Jan 2014

Partial Purification And Biochemical Characterization Of An Extremely Thermo- And Ph-Stable Esterase With Great Substrate Affinity, Esra Özbek, Yakup Kolcuoğlu, Leyla Konak, Ahmet Çolak, Fulya Öz

Turkish Journal of Chemistry

An esterase from a thermophilic bacterium, Geobacillus sp. DF20, was partially purified. Final purification factor was found to be 64.5-fold using Q-Sepharose ion exchange column chromatography. Native polyacrylamide gel electrophoresis indicated the presence of a single active esterase. The substrate specificity of this esterase was high for p-nitrophenyl butyrate (pNPB) substrate. The optimum pH and temperature for the enzyme activity were 7.0 and 50 ^°C, respectively. The pH and heat stability profiles show that this enzyme is more stable under neutral conditions at 50 ^°C. K_m and V_{max} values for this esterase acting on pNPB were 0.12 mM and 54.6 …


Adsorption Of The Urea Molecule On The B_{12}N_{12} Nanocage, Mohammad Taghi Baei Jan 2014

Adsorption Of The Urea Molecule On The B_{12}N_{12} Nanocage, Mohammad Taghi Baei

Turkish Journal of Chemistry

The adsorption of the urea molecule on the external surface of the B_{12}N_{12} nanocage was investigated using density functional theory (DFT) calculations. Adsorption of urea on the nanocage releases energies of about --23.70 to --29.50 kcal/mol with a significant NBO charge transfer from the urea to the nanocage. It was also found that the urea molecule can be strongly chemisorbed on the surface of the nanocage with Gibbs free energies of -7.91 to -14.81 kcal/mol. The HOMO--LUMO gap of the nanocage does not change significantly upon urea adsorption, while the Fermi level is dramatically changed from -4.27 eV in the …


The Effects Of Ionic Strength And Temperature On The Dissociation Constants Of Adefovir And Cidofovir Used As Antiviral Drugs, Hasan Atabey, Hayati̇ Sari Jan 2014

The Effects Of Ionic Strength And Temperature On The Dissociation Constants Of Adefovir And Cidofovir Used As Antiviral Drugs, Hasan Atabey, Hayati̇ Sari

Turkish Journal of Chemistry

The effects of ionic strength and temperature on the dissociation constants of adefovir (PMEA) and cidofovir (HPMPC) used as antiviral drugs were studied at 298 K, 308 K, and 318 K in aqueous media and at different ionic strength backgrounds of NaCl potentiometrically. The dissociation constants of the ligands were determined via the calculation of the titration data with the SUPERQUAD computer program. The thermodynamic parameters (\Delta G, \Delta H, and \Delta S) for all species were calculated. The dissociation order of nitrogen and oxygen atoms in the ligands according to proton affinities values were obtained using PM6 semiempirical methods. …


Synthesis Of Tertiary Propargylic Phosphonates By Addition Of Trialkynylaluminum Reagents To Acyl Phosphonates And Investigation Of Their Antimicrobial Activities, Muhammed Shakhawoat Hossain, Sidika Polat Çakir, Ayşe Betül Karaduman, Mustafa Yamaç, Ayhan Sitki Demi̇r Jan 2014

Synthesis Of Tertiary Propargylic Phosphonates By Addition Of Trialkynylaluminum Reagents To Acyl Phosphonates And Investigation Of Their Antimicrobial Activities, Muhammed Shakhawoat Hossain, Sidika Polat Çakir, Ayşe Betül Karaduman, Mustafa Yamaç, Ayhan Sitki Demi̇r

Turkish Journal of Chemistry

A series of propargylic alcohols containing phosphonates was synthesized by addition reactions of tris-(propynyl) and tris-(phenylethynyl)aluminum reagents to acyl phosphonates in good yields. Aromatic moieties of the acyl phosphonates with electron-withdrawing groups generally resulted in better isolated chemical yield. Selected propargylic phosphonates were tested for antimicrobial activities. Compounds 3a and 3h showed noticeable antifungal activity, especially against molds.


Coupling Ferrocene To Brominated Tetraazaporphyrin: Exploring An Alternative Synthetic Pathway For Preparation Of Ferrocene-Containing Tetraazaporphyrins, Victor N. Nemykin, Elena A. Makarova, Nathan R. Erickson, Pavlo V. Solntsev Jan 2014

Coupling Ferrocene To Brominated Tetraazaporphyrin: Exploring An Alternative Synthetic Pathway For Preparation Of Ferrocene-Containing Tetraazaporphyrins, Victor N. Nemykin, Elena A. Makarova, Nathan R. Erickson, Pavlo V. Solntsev

Turkish Journal of Chemistry

A Castro--Stephens coupling reaction between metal-free 3(2),8(7)-dibromo- 2(3),7(8),12(13),17(18)-tetra-tert-butyl-5,10,15,20-tetraazaporphyrin and (ferrocenylethynyl)copper resulted in the formation of copper 2(3),7(8),12(13), 17(18)-tetra-tert-butyl-3(2), 8(7)-di(ferrocenylethynyl)-5,10,15,20-tetraazaporphyrin and copper 2(3),7(8),12(13),17(18)-tetra-tert-butyl-3(2)-ferrocenylethynyl-5, 10,15,20-tetraazaporphyrin, which were separated in the form of 2 positional isomers along with copper 3(2)-bromo-2(3),7(8),12(13),17(18)-tetra-tert-butyl-5,10,15,20-tetraazaporphyrin and copper 2(3),7(8),12(13),17(18)-tetra-tert-butyl-5,10,15,20-tetraazaporphyrin. A similar reaction with metal-free 3(2),8(7),13(12), 18(17)-tetrabromo-2(3),7(8),12(13),17(18)-tetra-tert-butyl-5,10,15,20-tetraazaporphyrin resulted in only a trace amount of 3(2),8(7),13(12)-tribromo-2(3),7(8),12(13),17(18)-tetra-tert-butyl-18(17) -ferrocenylethynyl-5,10,15,20-tetraazaporphyrin, while no products with larger number of organometallic substituents were observed. Direct coupling between ferrocenelithium and 3(2),8(7)-dibromo-2(3),7(8),12(13),17(18)-tetra-tert-butyl-5,10,15,20-tetraazaporphyrin resulted in a debromination reaction accompanied by very minor dimerization of the tetraazaporphyrin core, which was explained based on the steric properties of the parent tetraazaporphyrin. The …


Microwave-Assisted Synthesis And Characterization Of Co(Ii) Phthalocyanine And Investigation Of Its Catalytic Activity On 4-Nitrophenol Oxidation, Ece Tuğba Saka, Zekeri̇ya Biyiklioğlu, Hali̇t Kanteki̇n Jan 2014

Microwave-Assisted Synthesis And Characterization Of Co(Ii) Phthalocyanine And Investigation Of Its Catalytic Activity On 4-Nitrophenol Oxidation, Ece Tuğba Saka, Zekeri̇ya Biyiklioğlu, Hali̇t Kanteki̇n

Turkish Journal of Chemistry

In this study, new cobalt phthalocyanine containing a 2-(2-benzothiazolylthio)ethoxy group at peripheral positions has been synthesized and characterized by spectroscopic methods (IR, UV-Vis elemental analysis, and mass spectroscopies). Catalytic activity of Co(II) phthalocyanine has been investigated in the presence of oxidants such as tert-buthylhydroperoxide, m-chloroperoxybenzoic acid, and H_2O_2. Co(II) phthalocyanine shows catalytically activity and product conversion under mild conditions. To find the optimal conditions in the oxidation process, substrate ratio, oxidant ratio, temperature, and oxidant type were examined over 3 h. The results exhibit the best optimum reaction conditions in this catalytic system.


Water-Soluble Phthalocyanines Containing Azo Dye; Microwave-Assisted Synthesis And Photochemical Properties Of Znpcs, Ci̇han Kantar, Emrah Ataci, Selami̇ Şaşmaz Jan 2014

Water-Soluble Phthalocyanines Containing Azo Dye; Microwave-Assisted Synthesis And Photochemical Properties Of Znpcs, Ci̇han Kantar, Emrah Ataci, Selami̇ Şaşmaz

Turkish Journal of Chemistry

Novel water-soluble metallophthalocyanines (M: Co, Ni, Cu, Zn) containing azo dye were characterized. The structures were confirmed by IR, UV/vis, ^1H NMR, ^{13}C NMR, mass spectroscopy, and elemental analysis. Photochemical properties and aggregation behavior of zinc phthalocyanines were investigated. Singlet oxygen quantum yields of the zinc phthalocyanines (2d, 3d, 5d, and 6d) were 0.8, 0.57, 0.71, and 0.46, respectively.


Synthesis Of Novel Triazoles Bearing 1,2,4-Oxadiazole And Phenylsulfonyl Groups By 1,3-Dipolar Cycloaddition Of Some Organic Azides And Their Biological Activities, Yaşar Dürüst, Hamza Karakuş, Muhsi̇ne Zeynep Yavuz, Ali̇ Akçahan Gepdi̇remen Jan 2014

Synthesis Of Novel Triazoles Bearing 1,2,4-Oxadiazole And Phenylsulfonyl Groups By 1,3-Dipolar Cycloaddition Of Some Organic Azides And Their Biological Activities, Yaşar Dürüst, Hamza Karakuş, Muhsi̇ne Zeynep Yavuz, Ali̇ Akçahan Gepdi̇remen

Turkish Journal of Chemistry

1,3-Dipolar cycloaddition of 5-azidomethyl-3-p-substituted phenyl-1,2,4-oxadiazoles to phenyl vinyl sulfone and bismaleimide gives rise straightforwardly to 1-((3-(p-substituted) phenyl-1,2,4-oxadiazol-5-yl)methyl)-4-(phenylsul\-fonyl)-4,5-dihydro-1H-1,2,3-triazoles and bisdihydropyrrolo[3,4-d][1,2,3]triazole-4,6(3aH,5H)-diones. The structures of the new cycloadducts were elucidated by means of IR, NMR (^1H, ^{13}C, 2D), mass spectra, and physical characteristics (mp and R_f values). In addition, anticancer activities of the cycloadducts against MCF-7 cells were also investigated.


Azolylimidazoles: Synthetic Strategies And Medicinal Applications, Bakr Fathy Abdelwahab, Rizk Elsayed Khidre Jan 2014

Azolylimidazoles: Synthetic Strategies And Medicinal Applications, Bakr Fathy Abdelwahab, Rizk Elsayed Khidre

Turkish Journal of Chemistry

The current review summarizes the known routes to different azoles linked directly to imidazole. This review is divided into classes based on the type of azoles connected to an imidazole ring. Some medical applications are mentioned.


On The Peculiar Reactivity Of A C,N-Annelated Isoindole Core, Iaroslav Baglai, Valerie Maraval, Zoia Vsevolodivna Voitenko, Carine Duhayon, Yulian Mihailovich Volovenko, Remi Chauvin Jan 2014

On The Peculiar Reactivity Of A C,N-Annelated Isoindole Core, Iaroslav Baglai, Valerie Maraval, Zoia Vsevolodivna Voitenko, Carine Duhayon, Yulian Mihailovich Volovenko, Remi Chauvin

Turkish Journal of Chemistry

C-, N-, and/or O-methylation products were generated from 11H-isoindolo[2,1-a]quinazoline-5-one upon treatment with NaH followed by iodomethane under air, and possible recrystallization from methanol. Two products were fully characterized by NMR and X-ray diffraction analysis. In accordance with the HSAB principle, this soft methylating agent (MeI) leads mainly to the C,C-dimethylated product 11,11-dimethyl-11H-isoindolo[2,1-a]quinazoline-5-one, which was previously not observed, beside the N-methylated product, in a procedure using methyl tosylate as a hard methylating agent of the same substrate in the initial absence of a base. A mechanism is finally proposed for the formation of methyl 2-(3-methyl-4-oxo-3,4-dihydroquinazolin-2-yl)benzoate as an oxidation side product.


Synthesis And X-Ray Powder Diffraction, Electrochemical, And Genotoxic Properties Of A New Azo-Schiff Base And Its Metal Complexes, Mustafa Bal, Gökhan Ceyhan, Bariş Avar, Muhammet Köse, Ahmet Kayraldiz, Mükerrem Kurtoğlu Jan 2014

Synthesis And X-Ray Powder Diffraction, Electrochemical, And Genotoxic Properties Of A New Azo-Schiff Base And Its Metal Complexes, Mustafa Bal, Gökhan Ceyhan, Bariş Avar, Muhammet Köse, Ahmet Kayraldiz, Mükerrem Kurtoğlu

Turkish Journal of Chemistry

A new, substituted 2-[(E)-{[4-(benzyloxy)phenyl]imino} methyl]-4-[(E)-(4-nitrophenyl)diazenyl]phenol azo-azomethine ligand (mbH) was synthesized from 2-hydroxy-5-[(4-nitrophenyl)diazenyl]benzaldehyde and 4-benzyloxyanilinehydrochloride in ethyl alcohol solution. These mononuclear Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) complexes of the ligand were prepared and their structures were proposed by elemental analysis, and infrared and ultraviolet-visible spectroscopy; the proton NMR spectrum of the mbH ligand was also recorded. The azo-azomethine ligand, mbH, behaves as a bidentate ligand coordinating through the nitrogen atom of the azomethine (--CH=N--) and the oxygen atom of the phenolic group. Elemental analyses indicated that the metal:ligand ratio was 1:2 in the metal chelates. Powder X-ray diffraction parameters suggested …


Effect Of Boric Acid On Corrosion And Electrochemical Performance Of Pb-0.08% Ca-1.1% Sn Alloys Containing Cu, As, And Sb Impurities For Manufacture Of Grids Of Lead-Acid Batteries, Said Salih, Ahmed Gad-Allah, Ashraf Abd El-Wahab, Hamid Abd Elrahman Jan 2014

Effect Of Boric Acid On Corrosion And Electrochemical Performance Of Pb-0.08% Ca-1.1% Sn Alloys Containing Cu, As, And Sb Impurities For Manufacture Of Grids Of Lead-Acid Batteries, Said Salih, Ahmed Gad-Allah, Ashraf Abd El-Wahab, Hamid Abd Elrahman

Turkish Journal of Chemistry

The electrochemical performance of lead-acid batteries made of Pb--Ca--Sn alloys with and without 0.1% of each of Cu, As, and Sb individually and combined in 4.0 M H_2SO_4 in the absence and presence of 0.4 M H_3BO_3 was studied. Both impurities and H_3BO_3 were found to reduce the corrosion rate. Cyclic voltammetry revealed that the presence of impurities or H_3BO_3 significantly retarded the formation of large crystal PbSO_4. H_3BO_3 increased the rates of oxygen and hydrogen evolution reactions for all alloys. Impedance measurement was used to quantify the amounts of PbSO_4 and PbO in the initial stage of the oxidation. …


Economic Synthesis Of Quinaldinium Fluorochromate(Vi), (Qnfc), And Solvent-Free Periodic Acid Oxidation Of Alcohols Catalyzed By Qnfc, Melek Özdemi̇r, Hati̇ce Beyti̇ye Özgün Jan 2014

Economic Synthesis Of Quinaldinium Fluorochromate(Vi), (Qnfc), And Solvent-Free Periodic Acid Oxidation Of Alcohols Catalyzed By Qnfc, Melek Özdemi̇r, Hati̇ce Beyti̇ye Özgün

Turkish Journal of Chemistry

A 1:1:1 stoichiometric reaction between CrO_3, aqueous HF, and quinaldine affords orange crystalline quinaldinium fluorochromate(VI) (QnFC) (C_{10}H_9NH[CrO_3F]) in 99.4% isolated yield. A highly efficient, simple, chemoselective, and environmentally benign procedure for QnFC (3 mol%) catalyzed oxidation of primary and secondary alcohols to aldehydes and ketones using 1.1 equiv of H_5IO_6 under solvent-free conditions is described.


Calixpenams: Synthesis, Characterization, And Biological Evaluation Of Penicillins V And X Clustered By Calixarene Scaffold, Fazel Nasuhi Pur, Karim Akbari Dilmaghani Jan 2014

Calixpenams: Synthesis, Characterization, And Biological Evaluation Of Penicillins V And X Clustered By Calixarene Scaffold, Fazel Nasuhi Pur, Karim Akbari Dilmaghani

Turkish Journal of Chemistry

Four 6-aminopenicillanic acid moieties were grafted at either rim of calix[4]arene, giving 2 novel generations of penicillin, which were named calixpenam. Antibiotic tests showed that they have amplified activity with respect to the corresponding penams against 3 gram-positive nonpenicillinase-producing strains of Streptococcus.


Performance Degradation Of Li_Xfepo_4 (X = 0, 1) Induced By Postannealing, Xiaofei Sun, Youlong Xu, Xiaoyu Zheng, Xiangfei Meng, Rui Zhang Jan 2014

Performance Degradation Of Li_Xfepo_4 (X = 0, 1) Induced By Postannealing, Xiaofei Sun, Youlong Xu, Xiaoyu Zheng, Xiangfei Meng, Rui Zhang

Turkish Journal of Chemistry

Olivine LiFePO_4 has been studied for more than a decade as a promising cathode material for rechargeable lithium batteries. However, the low electric conductivity and tap density still hinder its large-scale commercialization. Micro-sized LiFePO_4 is prepared by an optimized hydrothermal method in this paper. The influence of postannealing on the physicochemical properties of LiFePO_4 and FePO_4 is investigated to understand the plausible mechanism for performance degradation. It is found that postannealing even chemical delithiation greatly affects the particle size, morphology, pore distribution, surface area, and probably the lattice strain of Li_xFePO_4 (x = 0, 1). Consequently, the electrochemical performances of …


Convenient Method For Synthesis Of Various Fused Heterocycles Via Utility Of 4-Acetyl-5-Methyl-1-Phenyl-Pyrazole As Precursor, Sobhi Mohamed Gomha, Ahmad Sami Shawali, Abdou Osman Abdelhamid Jan 2014

Convenient Method For Synthesis Of Various Fused Heterocycles Via Utility Of 4-Acetyl-5-Methyl-1-Phenyl-Pyrazole As Precursor, Sobhi Mohamed Gomha, Ahmad Sami Shawali, Abdou Osman Abdelhamid

Turkish Journal of Chemistry

A new, less expensive, solvent-free procedure was developed for the synthesis of some new derivatives of various fused heterocyclic ring systems, namely azolopyridazine, azolotriazine, azinotriazine, thienopyridine, and pyrazolopyridine. The structures of the products prepared were established by their spectral data and elemental analyses. Eight compounds were evaluated for their in vitro antimicrobial activity. Some of the tested compounds exhibited moderate to significant antibacterial and antifungal activities.


Selective Synthesis Of Cyclododec-2-En-1-Yl Ethers Via Palladium-Catalyzed Allylic Substitution Reaction: A Kinetic Study, Asen Kolev, Magdalena Mitkova, Stefan Kotov, Encho Balbolov Jan 2014

Selective Synthesis Of Cyclododec-2-En-1-Yl Ethers Via Palladium-Catalyzed Allylic Substitution Reaction: A Kinetic Study, Asen Kolev, Magdalena Mitkova, Stefan Kotov, Encho Balbolov

Turkish Journal of Chemistry

The palladium-catalyzed reaction between isomeric cyclododec-2-en-1-yl acetates and primary aliphatic alcohols was found to result in high yields of the reaction products obtained. The selectivity with respect to cyclododec-2-en-1-yl ethers formed as reaction products ranged from 73% to 93%. The kinetics of the reaction of acetoxycyclododec-2-enes with alcohols was studied within the temperature range of 328--358 K. A kinetic equation best fitting the experimental data was provided.


Fluorescence Quenching Study Of Moxifloxacin Interaction With Calf Thymus Dna, Yunkai Lv, Pan Li, Miao-Lun Jiao, Bao-Sheng Liu, Chao Yang Jan 2014

Fluorescence Quenching Study Of Moxifloxacin Interaction With Calf Thymus Dna, Yunkai Lv, Pan Li, Miao-Lun Jiao, Bao-Sheng Liu, Chao Yang

Turkish Journal of Chemistry

Moxifloxacin (MOX) is a fourth-generation synthetic fluoroquinolone antibacterial agent with many important therapeutic properties. Fluorescence quenching was used to study the interaction of MOX with calf thymus DNA (ct-DNA) in aqueous solution. The intercalative binding mode and a static quenching mechanism were confirmed by the Stern--Volmer quenching rate constant (K_q) of 3.48 \times 10^{11} M^{-1} s^{-1} at 298 K. The thermodynamic parameters (\Delta H = --118.4 KJ mol^{-1} and \Delta S = --299.4 J mol^{-1} K^{-1}) were calculated at different temperatures, and they indicate that the main forces between MOX and ct-DNA are hydrogen bonding and Van der Waals force. …


Synthesis And Characterization Of New (E)-N'-(Substituted Benzylidene)-2-(3-(2-Methyl)-4-Oxo-3,4-Dihydroquinazolin-2-Ylthio)Acetohydrazides, Aamer Saeed, Shams-Ul Mahmood, Ulrich Flörke Jan 2014

Synthesis And Characterization Of New (E)-N'-(Substituted Benzylidene)-2-(3-(2-Methyl)-4-Oxo-3,4-Dihydroquinazolin-2-Ylthio)Acetohydrazides, Aamer Saeed, Shams-Ul Mahmood, Ulrich Flörke

Turkish Journal of Chemistry

A small library of new azomethine derivatives of 3-aryl-2-thioxo-2,3-dihydroquinazolin-4(1H)-ones was synthesized. The key intermediates 2-thioxo-quinazolinones (3a--e), obtained in 2 steps from the corresponding anilines, were treated with methyl chloroacetate to afford S-substituted esters (4a,d), which were then converted into corresponding acetohydrazides (5a,d). Further, acetohydrazide (5d) was converted to the azomethines derivatives (6a--k) by reacting with a number of suitably substituted benzaldehydes. FTIR, ^1H NMR, ^{13}C NMR, GC-MS, and elemental analyses were used to confirm the assigned structures of the synthesized compounds. Further, compounds 3a, 5, and 6j were also confirmed by X-ray diffraction data.


Application Of Guanidine And Its Salts In Multicomponent Reactions, Mahshid Rahimifard, Ghodsi Mohammadi Ziarani, Boshra Malekzadeh Lashkariani Jan 2014

Application Of Guanidine And Its Salts In Multicomponent Reactions, Mahshid Rahimifard, Ghodsi Mohammadi Ziarani, Boshra Malekzadeh Lashkariani

Turkish Journal of Chemistry

This review gives an overview of the application of guanidine and its salts in multicomponent reactions. It can act as a catalyst or solvent for multicomponent reactions or as a reagent for synthesis of substituted diazines, triazines, and macroheterocycles by multicomponent reactions.


Pw_{12}-Aptes@Mcf: Effective Nanosized Mesoporous Composites For The Oxidation Of Benzyl Alcohols, Razieh Fazaeli, Hamid Aliyan, Somaieh Parishani Foroushani, Zahra Mohagheghian Jan 2014

Pw_{12}-Aptes@Mcf: Effective Nanosized Mesoporous Composites For The Oxidation Of Benzyl Alcohols, Razieh Fazaeli, Hamid Aliyan, Somaieh Parishani Foroushani, Zahra Mohagheghian

Turkish Journal of Chemistry

The surface of mesocellular silica foam (MCF) was modified by grafting 3-aminopropyl-triethoxysilane (APTES) to have a positive charge, and thus to provide sites for the immobilization of H_3PW_{12}O_{40} (PW_{12}). This modified nanosized mesoporous silica (PW_{12}-APTES@MCF) was characterized by FTIR, XRD, BET, and TEM. XRD and adsorption--desorption analysis shows that the mesostructure of silica remains intact after various modifications, while the spectral technique shows the successful grafting of the neat PW_{12} inside the porous silica support. The oxidation of alcohols occurs effectively and selectively with H_2O_2 as the oxidant. PW_{12}-APTES@MCF was used as the catalyst. The catalyst can be reused several …


Te(Ii)-Induced Heterocyclization Of 1,2-Alkadienephosphonates, Dobromir Dimitrov Enchev Jan 2014

Te(Ii)-Induced Heterocyclization Of 1,2-Alkadienephosphonates, Dobromir Dimitrov Enchev

Turkish Journal of Chemistry

The reactivity of some 1,2-alkadienephosphonates towards phenyltelluryl halides was investigated. A plausible mechanism of the reaction is discussed.


Synthesis, Spectral Characterisation, Electrochemical, And Fluorescence Studies Of Biologically Active Novel Schiff Base Complexes Derived From E-4-(2-Hydroxy-3-Methoxybenzlideneamino)-N-(Pyrimidin-2-Yl)Benzenesulfonamide, Valarmathy Govindaraj, Subbalakshmi Ramanathan Jan 2014

Synthesis, Spectral Characterisation, Electrochemical, And Fluorescence Studies Of Biologically Active Novel Schiff Base Complexes Derived From E-4-(2-Hydroxy-3-Methoxybenzlideneamino)-N-(Pyrimidin-2-Yl)Benzenesulfonamide, Valarmathy Govindaraj, Subbalakshmi Ramanathan

Turkish Journal of Chemistry

A new Schiff base was prepared from 2-sulphanilamidopyrimidine and 2-hydroxy-3-methoxybenzaldehyde in ethanolic media and it was complexed with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) ions. The synthesised ligand and complexes were characterised by IR, UV, ^1H and ^{13}C NMR, elemental analysis, cyclic voltammetry, EPR, molar conductance, and magnetic susceptibility. The reasonable shifts in FT-IR and NMR spectral signals of the complexes with respect to the free ligand confirm good coordination of the Schiff-base ligand with the metal through imine nitrogen and oxygen atoms of Schiff base moiety. The Schiff-base ligand and the complexes were screened for antimicrobial activity and fluorescent …


Development Of 2-Acetylpyridine-4-Phenyl-3-Thiosemicarbazone Functionalized Polymeric Resin For The Preconcentration Of Metal Ions Prior To Their Ultratrace Determinations By Mis-Faas, Ali Nawaz Siyal, Saima Qayoom Memon, Aydan Elçi̇, Ümi̇t Di̇vri̇kli̇, Muhammad Yar Khuhawar, Lati̇f Elçi̇ Jan 2014

Development Of 2-Acetylpyridine-4-Phenyl-3-Thiosemicarbazone Functionalized Polymeric Resin For The Preconcentration Of Metal Ions Prior To Their Ultratrace Determinations By Mis-Faas, Ali Nawaz Siyal, Saima Qayoom Memon, Aydan Elçi̇, Ümi̇t Di̇vri̇kli̇, Muhammad Yar Khuhawar, Lati̇f Elçi̇

Turkish Journal of Chemistry

2-Acetylpyridine-4-phenyl-3-thiosemicarbazone (APPT) ligand was incorporated onto Amberlite XAD-2 resin through an azo spacer and characterized by FTIR spectroscopy, elemental analysis, TGA, and SEM analysis. The synthesized resin was used for the preconcentration of Pb(II), Zn(II), Co(II), Ni(II), Cu(II), and Cd(II) ions. The sorbed metal ions were eluted with 10 mL of 2.0 mol L^{-1} HCl and determined by microsample injection coupled flame atomic spectrometry (MIS-FAAS). The recoveries of studied metal ions were \ge 95.1 % with RSD \ge 4.0 % at optimum pH 8; resin amount, 300 mg; flow rates, 2.0 mL min^{-1} (of eluent) and 3.0 mL min^{-1} (sample …


Antioxidant, Anticholinesterase, And Antimicrobial Activities And Fatty Acid Constituents Of Achillea Cappadocica Hausskn. Et Bornm., Abdulselam Ertaş, Mehmet Boğa, Nesri̇n Haşi̇mi̇, Yeter Yeşi̇l, Ahmet Ceyhan Gören, Gülaçti Topçu, Ufuk Kolak Jan 2014

Antioxidant, Anticholinesterase, And Antimicrobial Activities And Fatty Acid Constituents Of Achillea Cappadocica Hausskn. Et Bornm., Abdulselam Ertaş, Mehmet Boğa, Nesri̇n Haşi̇mi̇, Yeter Yeşi̇l, Ahmet Ceyhan Gören, Gülaçti Topçu, Ufuk Kolak

Turkish Journal of Chemistry

This study was the first fatty acid analysis and biological activity report on an endemic Achillea species, Achillea cappadocica Hausskn. et Bornm. The major compounds in the fatty acid were identified as oleic (34.7 %), palmitic (23.1 %), and linoleic acids (20.6 %). The methanol and water extracts indicated higher ABTS cation radical scavenging activity than that of \alpha-tocopherol and BHT at 100 \mu g/mL. The acetone extract showed 70.62 % inhibitory activity against butyrylcholinesterase at 200 \mu g/mL. The acetone and methanol extracts exhibited moderate antimicrobial activity.


Oxidation Of Hydrocarbons With Tetra-N-Butylammonium Peroxy Monosulfate Catalyzed By \Beta-Tetrabromo-Meso-Tetrakis(4-Methoxyphenyl)- And \Beta-Tetrabromo-Meso-Tetraphenylporphyrinatomanganese(Iii), Saeed Rayati, Saeed Zakavi, Hossein Valinejad Jan 2014

Oxidation Of Hydrocarbons With Tetra-N-Butylammonium Peroxy Monosulfate Catalyzed By \Beta-Tetrabromo-Meso-Tetrakis(4-Methoxyphenyl)- And \Beta-Tetrabromo-Meso-Tetraphenylporphyrinatomanganese(Iii), Saeed Rayati, Saeed Zakavi, Hossein Valinejad

Turkish Journal of Chemistry

\beta-Tetrabromo-meso-tetrakis(4-methoxyphenyl)porphyrin, H_2T(4-OCH_3P)PBr_4, was synthesized and characterized by UV-Vis and ^1H NMR spectroscopy. Oxidation of alkanes and olefins with tetra-n-butylammonium peroxymonosulfate (n-Bu_4NHSO_5) was studied in the presence of MnT(4-OCH_3P)PBr_4(OAc) and MnTPPPBr_4(OAc) (TPP = meso-tetraphenylporphyrin). While significance differences were observed between the catalytic activities of the title complexes in the oxidation of alkanes, the 2 manganese porphyrins showed comparable activities in oxidation of most of the olefins used. However, the latter showed greater catalytic performance in the oxidation of the hydrocarbons. Moreover, the oxidative degradation of the former (60 %) was greater than that of the latter (45 %) in the oxidation …


Organic Biomolecules Bind To Phosphate Through Borate Linkages In Aqueous Solutions, Nazi̇k Aydoğmuş, Dursun Ali̇ Köse, Michael Andrew Beckett, Bi̇rgül Karan Jan 2014

Organic Biomolecules Bind To Phosphate Through Borate Linkages In Aqueous Solutions, Nazi̇k Aydoğmuş, Dursun Ali̇ Köse, Michael Andrew Beckett, Bi̇rgül Karan

Turkish Journal of Chemistry

Solutions of salicyclic, ascorbic, and citric acids were reacted with boric acid, followed by NaH_2PO_4. The products, triphosphateborate ester of salicylic acid (1), orthosphateborate ester of ascorbic acid (2), triphosphateborate ester of ascorbic acid (3), and orthosphateborate ester of citric acid (4), were flash precipitated with cold acetone and characterised by microanalysis, thermal analysis, FT-IR, Raman, ^{11}B NMR, ^{31}P MAS NMR, and mass spectroscopic techniques. Analytical results indicated the presence of --C--O--B--O--P-- linkages with the attached phosphate groups varying between orthophosphate and triphosphate, depending on the starting material. The biomolecules studied in this work may serve as models in the …


N-Heterocyclic Carbene (Nhc) Palladium(Ii) Complexes Bearing Chiral Oxazoline Ligands And Their Catalytic Activities In Allylic Alkylation Reactions, Serpi̇l Deni̇zalti, Hayati̇ Türkmen, Beki̇r Çeti̇nkaya Jan 2014

N-Heterocyclic Carbene (Nhc) Palladium(Ii) Complexes Bearing Chiral Oxazoline Ligands And Their Catalytic Activities In Allylic Alkylation Reactions, Serpi̇l Deni̇zalti, Hayati̇ Türkmen, Beki̇r Çeti̇nkaya

Turkish Journal of Chemistry

NHC--Pd(II) complexes bearing a chiral oxazoline ligand (IIIa--f) were synthesized by cleavage of dimeric palladium complexes with the oxazoline ligand. They were fully characterized by ^1H and ^{13}C NMR and elemental analyses. The catalytic activity of the complexes (IIIa--f) in allylic alkylation reactions was evaluated. The complex IIIa was found to be the most active catalyst. Very low ee values indicate that the oxazoline is dissociated from the active catalytic species.