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Full-Text Articles in Physical Sciences and Mathematics
Synthesis, Characterization, And Metal Extraction Studies Of A New Macrobicyclic Ligand, Hali̇l Zeki̇ Gök, Yaşar Gök, Esra Eker
Synthesis, Characterization, And Metal Extraction Studies Of A New Macrobicyclic Ligand, Hali̇l Zeki̇ Gök, Yaşar Gök, Esra Eker
Turkish Journal of Chemistry
This article describes the synthesis, characterization, and metal ion binding properties of a new macrobicyclic ligand. Solvent extraction experiments were performed in order to determine the extraction behavior of new macrobicyclic ligand towards selected metal cations. Selective extraction of heavy metals and precious metals is highly demanded due to their toxicity and commercial importance. Based on our experimental results, macrobicyclic ligand 3 demonstrated remarkable affinity towards the Ag^+ ion by 96.7% and 96.9% to the dichloromethane and chloroform phases, respectively. The extraction experiments with macrobicyclic ligand 3 for the Ag^+ ion were repeated at different temperatures to calculate thermodynamic parameters. …
Two New Coordination Polymers Containing Dicyanidoargentate(I) And Dicyanidoaurate(I): Synthesis And Characterization, And A Detailed In Vitro Investigation Of Their Anticancer Activities On Some Cancer Cell Lines, Ali̇ Aydin, Ahmet Karadağ, Şaban Teki̇n, Nesri̇n Korkmaz, Aslihan Özdemi̇r
Two New Coordination Polymers Containing Dicyanidoargentate(I) And Dicyanidoaurate(I): Synthesis And Characterization, And A Detailed In Vitro Investigation Of Their Anticancer Activities On Some Cancer Cell Lines, Ali̇ Aydin, Ahmet Karadağ, Şaban Teki̇n, Nesri̇n Korkmaz, Aslihan Özdemi̇r
Turkish Journal of Chemistry
Two novel cyanido-bridged bimetallic polymeric complexes, [Ni(edbea)Ag$_{3}$(CN)$_{5}$]$_{n} $(C1) and [Ni(bishydeten) Au$_{2}$(CN)$_{4}$]$_{n}$ (C2), where edbea = [2,2$' $-(ethylenedioxy)bis(ethylamine)] and bishydeten = [($N$,$N' $-bis(2-hydroxyethyl) ethylenediamine)] are ligands, were synthesized and characterized by elemental, infrared, and thermal measurement techniques and investigated for their biological activity in cultured cancer cell lines. The results show that both compounds and free anions, [Ag(CN)$_{2}$]$^{-}$ and [Au(CN)$_{2}$]$^{-}$, exhibited very high antiproliferative activity compared to the anticancer drug 5FU against the cancer cell lines tested. The antiproliferative and cytotoxic activities of C1 and C2 were significantly lower than those of free anions, indicating that the extreme cytotoxicity of free …
Synthesis Of Bis-Thiazoles, Bis-Pyrazoles, Bis-Hydrazonates, And Bis-Triazolothiadiazoles Based On Bis-Hydrazonoyl And Bis-Hydrazones, Abdelwahed Sayed
Synthesis Of Bis-Thiazoles, Bis-Pyrazoles, Bis-Hydrazonates, And Bis-Triazolothiadiazoles Based On Bis-Hydrazonoyl And Bis-Hydrazones, Abdelwahed Sayed
Turkish Journal of Chemistry
A facile synthesis of bis-thiazoles, bis-pyrazoles, and bis-hydrazonates from the reaction of bis-hydrazonoyl dichlorides with different moieties is described. Bis-triazolothiadiazoles were synthesized via oxidative cyclization of bis-hydrazones. Structures of the final product were elucidated by elemental analyses and spectral data.
Kinetics Study And Influence Of Water-Soluble Polymer On The Electrodeposition Of Iron From A Citrate-Chloride Electrolyte On The Basis Of Fe(Iii), Vyacheslav Protsenko, Felix Danilov
Kinetics Study And Influence Of Water-Soluble Polymer On The Electrodeposition Of Iron From A Citrate-Chloride Electrolyte On The Basis Of Fe(Iii), Vyacheslav Protsenko, Felix Danilov
Turkish Journal of Chemistry
The kinetics of the iron electrodeposition reaction from a plating bath containing trivalent iron ions is investigated in the present work. The electrochemical reaction is stated to proceed via the formation of relatively stable intermediates: Fe(II) ions. Only a part of the total amount of Fe(II) ions formed at the first stage of Fe(III) discharge is reduced further, producing metal iron. The effect of polyhexamethyleneguanidine hydrochloride (with an average molecular weight of 1000) on the iron deposition is ascertained. The presence of polymer additive in the iron electrolyte appreciably affects the rate of iron deposition, while the polymer additive does …
Characterization Of A Cu$^{2+}$-Selective Fluorescent Probe Derived From Rhodamine B With 1,2,4-Triazole As Subunit And Its Application In Cell Imaging, Na Li, Chunwei Yu, Yuxiang Ji, Jun Zhang
Characterization Of A Cu$^{2+}$-Selective Fluorescent Probe Derived From Rhodamine B With 1,2,4-Triazole As Subunit And Its Application In Cell Imaging, Na Li, Chunwei Yu, Yuxiang Ji, Jun Zhang
Turkish Journal of Chemistry
A rhodamine B derivative containing 1,2,4-triazole as subunit was characterized as an "off-on" type Cu$^{2+}$-selective fluorescent probe. It exhibited high selectivity and sensitivity for Cu$^{2+}$ in ethanol-water solution (9:1, v:v, pH 7.0, 20 mM HEPES) and underwent ring opening. A prominent fluorescence enhancement at 570 nm was observed in the presence of Cu$^{2+}$ with the change in the absorption spectrum, and a 1:1 metal-ligand complex was formed. With the optimized experimental conditions, the probe exhibited a dynamic response range for Cu$^{2+}$ from 8.0 $\times $ 10$^{-7}$ to 7.5 $\times $ 10$^{-6}$ M with a detection limit of 2.3 $\times $ …
Acid-Free Synthesis Of S-Nitrosothiols At Neutral Ph By Shock-Freezing In Liquid Nitrogen, Dimitrios Tsikas, Anke Böhmer, Arne Trettin, Arslan Arinç Kayaçelebi̇
Acid-Free Synthesis Of S-Nitrosothiols At Neutral Ph By Shock-Freezing In Liquid Nitrogen, Dimitrios Tsikas, Anke Böhmer, Arne Trettin, Arslan Arinç Kayaçelebi̇
Turkish Journal of Chemistry
A laboratory method for the acid-free synthesis of S-nitrosothiols (RSNO) from NaNO$_{2}$ and thiols in aqueous buffer of neutral pH is reported. Equimolar amounts of NaNO$_{2}$ and thiol are added to a 100-$\mu $M Na$_{4}$EDTA-containing Na$_{2}$HPO$_{4}$ buffer (100 mM, pH 7.4). Samples are set into liquid nitrogen for 1 min and then thawed to room temperature or in an ice bath. Dependent upon the RSNO, repetition of the procedure may be required. This method may be of particular importance when the classical acid-based method fails or releases harmful gases such as H$_{2}$S.
Sustainable Activity Of Hydrothermally Synthesized Mesoporous Silicates In Acetic Acid Esterification, Veli̇ Şi̇mşek, Levent Deği̇rmenci̇, Kirali̇ Mürtezaoğlu
Sustainable Activity Of Hydrothermally Synthesized Mesoporous Silicates In Acetic Acid Esterification, Veli̇ Şi̇mşek, Levent Deği̇rmenci̇, Kirali̇ Mürtezaoğlu
Turkish Journal of Chemistry
A hydrothermal method was applied in the synthesis of mesoporous silicates containing silicotungstic acid (STA). The synthesis procedures were developed by modification of procedures previously applied in the synthesis of MCM-41 and SBA-15. The synthesized catalysts were named MCM-41-S and SBA-15-S based on MCM-41 and SBA-15. Their activities were investigated in ethyl acetate production, which was selected as the model reaction. The results indicated that the activity of SBA-15-S catalysts increased with increasing STA in the catalyst. Reaction experiments were also conducted in identical conditions in the presence of catalysts recovered after the reaction. The results indicated that sustainable activity …
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
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.
Synthesis, Biological Evaluation, And Molecular Docking Of N'-(Aryl/Alkylsulfonyl)-1-(Phenylsulfonyl) Piperidine-4-Carbohydrazide Derivatives, Hira Khalid, Aziz Ur Rehman, Muhammad Athar Abbasi, Rashad Hussain, Khalid Mohammad Khan, Muhammad Ashraf, Syeda Abida Ejaz, Muhammad Qaiser Fatmi
Synthesis, Biological Evaluation, And Molecular Docking Of N'-(Aryl/Alkylsulfonyl)-1-(Phenylsulfonyl) Piperidine-4-Carbohydrazide Derivatives, Hira Khalid, Aziz Ur Rehman, Muhammad Athar Abbasi, Rashad Hussain, Khalid Mohammad Khan, Muhammad Ashraf, Syeda Abida Ejaz, Muhammad Qaiser Fatmi
Turkish Journal of Chemistry
A series of new N'-[(alkyl/aryl)sulfonyl]-1-(phenylsulfonyl)piperidine-4-carbohydrazide derivatives were synthesized. Starting from ethyl piperidine-4-carboxylate (a), first ethyl 1-(phenylsulfonyl)piperidine-4-carboxylate (1), second 1-(phenylsulfonyl)piperidine-4-carbohydrazide (2), and finally N'-[(alkyl/aryl)sulfonyl]-1-(phenylsulfonyl)piperidine-4-carbohydrazides (4a--n) were synthesized by reacting 2 with alkyl/aryl sulfonyl chlorides (3a--n). The structures of the synthesized compounds were characterized by IR, ^1H-NMR, and EI-MS spectra and all were screened in vitro for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzyme inhibition activities. Molecular docking was accomplished for these compounds to examine their binding interactions with AChE and BChE human proteins. The strategy we applied for this purpose was a direct receptor-based approach. The binding modes of the inhibitors …
Fluorescence Quenching Study Of Moxifloxacin Interaction With Calf Thymus Dna, Yunkai Lv, Pan Li, Miao-Lun Jiao, Bao-Sheng Liu, Chao Yang
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. …
Calixcephems: Clustered Cephalosporins Analogous To Calixpenams As Novel Potential Anti-Mrsa Agents, Fazel Nasuhi Pur, Karim Akbari Dilmaghani
Calixcephems: Clustered Cephalosporins Analogous To Calixpenams As Novel Potential Anti-Mrsa Agents, Fazel Nasuhi Pur, Karim Akbari Dilmaghani
Turkish Journal of Chemistry
Two novel clusters of cephalosporin based on calixarene were synthesized directly or by ring expansion of the penicillin arms of calixpenams to the corresponding cephem arms via sulfoxide intermediates. Antibiotic tests showed that calixcephems have a noteworthy increase in antibacterial activity against methicillin-resistant strains of Staphylococcus aureus (MRSA) with respect to parent calixpenams and their corresponding single cephems.
Synthesis Of New Pyrazole And Antibacterial Pyrazolopyrimidine Derivatives, Ameur Rahmouni, Anis Romdhane, Abderrahim Ben Said, Kaouther Majouli, Hichem Ben Jannet
Synthesis Of New Pyrazole And Antibacterial Pyrazolopyrimidine Derivatives, Ameur Rahmouni, Anis Romdhane, Abderrahim Ben Said, Kaouther Majouli, Hichem Ben Jannet
Turkish Journal of Chemistry
3-Substituted-1-phenyl-1H-pyrazolo[3,4-d]pyrimidin-4-amines 2a--c were synthesized by treating 5-aminopyrazole-4-carbonitriles 1a--c with formamide. The reactivity of compounds 1a--c towards some cyclic anhydrides was studied. The condensation of 5-aminopyrazole-4-carbonitrile 1b with triethylorthoformate gives imidate 7b, which reacts with a series of primary amines and leads to pyrazolo[3,4-d]pyrimidine-4-amines 9 and 10. The reaction of imidate 7b with ammonia and hydroxylamine afforded pyrazolopyrimidine 2b and pyrazolo[3,4-d]pyrimidin-5-(4H)-ol 11, respectively. The synthesized compounds were completely characterized by ^1H NMR, ^{13}C NMR, IR, and HRMS. The antibacterial activity of some new synthesized compounds was evaluated and appeared to be significant.
Selective Catalytic Reduction Of Sulfur Dioxide By Carbon Monoxide Over Iron Oxide Supported On Activated Carbon, Guangjian Wang, Liancheng Bing, Zhijian Yang, Jiankang Zhang
Selective Catalytic Reduction Of Sulfur Dioxide By Carbon Monoxide Over Iron Oxide Supported On Activated Carbon, Guangjian Wang, Liancheng Bing, Zhijian Yang, Jiankang Zhang
Turkish Journal of Chemistry
The selective reduction of sulfur dioxide with carbon monoxide to elemental sulfur was studied over AC-supported transition-metal oxide catalysts. According to the study, Fe_2O_3/AC was the most active catalyst among the 4 AC-supported catalysts tested. By using Fe_2O_3/AC, the best catalyst, when the feed conditions were properly optimized (CO/SO_2 molar ratio = 2:1; sulfidation temperature, 400 °C; Fe content, 20 wt%; GHSV = 7000 mL g^{-1} h^{-1}), 95.43% sulfur dioxide conversion and 86.59% sulfur yield were obtained at the temperature of 350 °C. Catalyst samples were characterized by X-ray powder diffraction in order to relate the phase composition to the …
Spectrophotometric Determination Of Molybdenum Using Surfactant-Mediated Liquid--Liquid Extraction, Rameshwar Dass, Jitander Kumar Kapoor, Sunita Gambhir
Spectrophotometric Determination Of Molybdenum Using Surfactant-Mediated Liquid--Liquid Extraction, Rameshwar Dass, Jitander Kumar Kapoor, Sunita Gambhir
Turkish Journal of Chemistry
A new spectrophotometric method has been developed for determination of molybdenum using surfactant-mediated liquid--liquid extraction. Molybdenum(V) obtained by ascorbic acid reduction in 2.5 M H_2SO_4 reacted spontaneously with thiocyanate and cetyl trimethyl ammonium bromide (CTAB), forming an intense orange yellow complex that was extracted quantitatively into 1,2-dichloroethane and absorbed at 460 nm. The absorbance of the extract was found to be stable for more than 24 h. Beer's law was obeyed over the concentration range 0.1--4.2 \mu g Mo mL^{-1} of the extract. The linear range for an accurate determination was found to be 1.2--2.6 \mu g Mo mL^{-1}. The …
Application Of Guanidine And Its Salts In Multicomponent Reactions, Mahshid Rahimifard, Ghodsi Mohammadi Ziarani, Boshra Malekzadeh Lashkariani
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.
Preparation And Characterization Of Nonmetal Promoter Modified Cuznal Catalysts For Higher Alcohol From Synthesis Gas Through Complete Liquid Phase Method, Shirui Yu, Xiaodong Wang, Wei Huang
Preparation And Characterization Of Nonmetal Promoter Modified Cuznal Catalysts For Higher Alcohol From Synthesis Gas Through Complete Liquid Phase Method, Shirui Yu, Xiaodong Wang, Wei Huang
Turkish Journal of Chemistry
A complete liquid phase technology and a function regulator were applied to prepare CuZnAl catalysts for higher alcohol synthesis. Characterizations showed that the introduction of the function regulator can change the reduction ability of copper oxides and the surface basicity of catalysts. Activity tests indicated that the selectivity of higher alcohol is high when considerable medium-strong basicity and the synergistic effects of copper ion and metal copper exist on the catalytic surface. The optimized modified CuZnAl catalyst without any metal additives provides a CO conversion of 28.9%, C_{2+}OH selectivity of up to 42.8%, and hydrocarbon selectivity of 2.5%, with a …
Crystal Growth Morphology Of Magnesium Hydroxide, Jiansong Wu, Juan Du, Yi-Min Gao
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 …
Te(Ii)-Induced Heterocyclization Of 1,2-Alkadienephosphonates, Dobromir Dimitrov Enchev
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.
Novel N-Acyl/Aroyl-2-(5-Phenyl-2h-Tetrazol-2-Yl)Acetohydrazides: Synthesis And Characterization, Aamer Saeed, Majid Hussain, Muhammad Qasim
Novel N-Acyl/Aroyl-2-(5-Phenyl-2h-Tetrazol-2-Yl)Acetohydrazides: Synthesis And Characterization, Aamer Saeed, Majid Hussain, Muhammad Qasim
Turkish Journal of Chemistry
A number of novel N-acyl/aroyl-2-(5-phenyl-2H-tetrazol-2-yl)acetohydrazides (4a--j) of biological interest were efficiently synthesized by treating 2-(5-phenyl-2H-tetrazole-2-yl)acetohydrazide (3) with a variety of aroyl/hetero- cyclyl or alkanoyl chlorides. FTIR, ^1H NMR, ^{13}C NMR, GC-MS, and elemental analyses data confirmed the structures assigned to the newly synthesized compounds.
Synthesis And Phase Transition Studies Of New Dimer Compounds Connected To A 1,3-Dimethylbarbituric Acid Core, Abdulkarim-Talaq Mohammad, Guan-Yeow Yeap, Hasnah Osman
Synthesis And Phase Transition Studies Of New Dimer Compounds Connected To A 1,3-Dimethylbarbituric Acid Core, Abdulkarim-Talaq Mohammad, Guan-Yeow Yeap, Hasnah Osman
Turkish Journal of Chemistry
A series of dimeric unsymmetrical liquid crystals derived from heterocyclic 1,3-dimethylbarbituric acid exhibiting smectic A and nematic phase are reported. All compounds were prepared by the condensation of 4'-(R-(4-formylphenoxy)butoxy)biphenyl-4-carboxylate with 1,3-dimethylbarbituric acid in ethanol. The mesomorphic properties were investigated by DSC and POM, where the type of phase depends on the length of spacer alkoxy chains and the length of the terminal chain. While the SmA phase was observed upon the heating and cooling run when the spacer alkoxy chains carbon numbers increased (n = 6), the N phase was observed when the length of spacer alkoxy chains increased (n …
Investigation Of The Adsorption Kinetics Of Methylene Blue Onto Cotton Wastes, Bi̇lal Acemi̇oğlu, Murat Ertaş, Mehmet Hakki Alma, Mustafa Usta
Investigation Of The Adsorption Kinetics Of Methylene Blue Onto Cotton Wastes, Bi̇lal Acemi̇oğlu, Murat Ertaş, Mehmet Hakki Alma, Mustafa Usta
Turkish Journal of Chemistry
Cotton stalk (CS), cotton waste (CW), and cotton dust (CD), which are cotton wastes, were used as adsorbents to study the adsorption kinetics of methylene blue from aqueous solution. Kinetics of the batch adsorption experiment was investigated according to the pseudo-first order, the pseudo-second order, and the intraparticle diffusion models used commonly in the literature. The effects of the initial concentration, solution pH, and temperature on kinetic parameters (adsorption rate constant, initial adsorption rate, equilibrium adsorption capacity, etc.) were studied. The results showed that the adsorption process was well fitted to the pseudo-second order model for all adsorbents. The activation …
Facile Synthesis Of 5-Bromotropono[C]-Fused Pyrazoles And Isoxazole, Yang Li, Liangyu Xu, Wentao Gao
Facile Synthesis Of 5-Bromotropono[C]-Fused Pyrazoles And Isoxazole, Yang Li, Liangyu Xu, Wentao Gao
Turkish Journal of Chemistry
A facile synthesis of a series of new 5-bromotropono[c]pyrazole derivatives (3 and 10--15) as well as 5-bromotropono[c]isoxazole (17) is described, involving a condensation reaction of 3-acetyl-5-bromotropolone (1) with hydrazine monohydrate (2), arylhydrazine hydrochlorides (4--9), and hydroxylamine hydrochloride (16), respectively. All the synthesized compounds were obtained in good yields of 56%--77% and their structures were characterized by spectral data and HRMS.
Solvent Extraction Of Praseodymium(Iii) From Acidic Nitrate Medium Using Cyanex 921 And Cyanex 923 As Extractants In Kerosene, Nandita Panda, Nihar Bala Devi, Sujata Mishra
Solvent Extraction Of Praseodymium(Iii) From Acidic Nitrate Medium Using Cyanex 921 And Cyanex 923 As Extractants In Kerosene, Nandita Panda, Nihar Bala Devi, Sujata Mishra
Turkish Journal of Chemistry
Solvent extraction of praseodymium(III) from acidic nitrate medium by the neutral organophosphorous extractants Cyanex 921 and Cyanex 923 in kerosene was studied. The effects of various parameters like equilibration time, nitric acid concentration, nitrate ion concentration, extractant concentration, temperature, and nature of diluents on the extraction behavior of Pr(III) were investigated. The extraction of 0.001 M Pr(III) was quantitative (93%) from the aqueous phase containing 0.001 M HNO_3 and 0.1 M KNO_3 using 0.5 M Cyanex 921/1 M Cyanex 923. On the basis of slope analysis, the compositions of the extracted species were formulated as Pr(NO_3)_3.2Cyanex 921 and Pr (NO_3)_3.Cyanex …
In Vitro Effects Of Pesticide Exposure On The Activity Of The Paraoxonase-1 Enzyme From Sheep Liver Microsomes, Büşra Cebeci̇, Zuhal Alim, Şükrü Beydemi̇r
In Vitro Effects Of Pesticide Exposure On The Activity Of The Paraoxonase-1 Enzyme From Sheep Liver Microsomes, Büşra Cebeci̇, Zuhal Alim, Şükrü Beydemi̇r
Turkish Journal of Chemistry
The organophosphate target enzyme paraoxonase-1 (PON1) has been extensively studied in toxicology. Pesticides are organophosphate compounds that are commonly used in agriculture. They are also used as nerve gases, such as sarin and soman. Therefore, the effects of these compounds on enzymatic activity are well known. In the present study, we investigated the in vitro effects of fenoxaprop-p-ethyl, lambda cyhalothrin, imidacloprid, and dichlorvos pesticides on sheep liver microsomal PON1. The enzyme was purified approximately 141-fold with a specific activity of 1822.22 EU/mg proteins. The pesticides inhibited sheep liver PON1 in vitro, and the IC_{50} values for these compounds were 0.0103, …
Adsorption Of The Urea Molecule On The B_{12}N_{12} Nanocage, Mohammad Taghi Baei
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 …
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
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 …
Application Of 3-Aroyl-4(5)-Arylimidazols As Efficient Ligands In Pd-Catalyzed Heck Reactions, Mojtaba Amini, Seyedeh Motahhareh Amini, Bagher Eftekhari-Sis, Ali Keivanloo
Application Of 3-Aroyl-4(5)-Arylimidazols As Efficient Ligands In Pd-Catalyzed Heck Reactions, Mojtaba Amini, Seyedeh Motahhareh Amini, Bagher Eftekhari-Sis, Ali Keivanloo
Turkish Journal of Chemistry
The Heck coupling of haloarenes with various alkenes was successfully performed in the presence of 0.25 mol % PdCl_2 and 0.5 mol % biphenyl-4-yl-[4(5)-(biphenyl-4-yl)-1H-imidazol-2-yl]ketone 2f as a ligand with Na_2CO_3 as optimal base, in a 1:1 mixture of H_2O/DMF as the reaction solvent at 80 ^°C for 8 h. Imidazole 2f was found to be an inexpensive, air-stable, easily available, and efficient ligand in the palladium-catalyzed Heck reactions of aryl iodides (76 %--94 %), bromides (52 %--79 %), and chlorides (40 %--70 %).
Selective Co Methanation Over Ceo_2--Zro_2-Composed Nio And Co_3o_4 Catalysts, Fi̇li̇z Derekaya, Derya Ermergen
Selective Co Methanation Over Ceo_2--Zro_2-Composed Nio And Co_3o_4 Catalysts, Fi̇li̇z Derekaya, Derya Ermergen
Turkish Journal of Chemistry
CeO_2--ZrO_2-composed NiO and Co_3O_4 catalysts were prepared by 3 different methods. Both CO methanation and selective CO methanation were carried out. All catalysts were prepared by (1) co-precipitation, (2) surfactant-assisted co-precipitation, and (3) surfactant-assisted co-precipitation with ultrasound mixing methods. Catalysts were characterized by using N_2 physisorption, XRD, SEM, TEM, and TPR-H_2 techniques. The highest surface area value, uniform pore size distribution, and pores having small diameters were observed for the catalysts prepared by using the surfactant and ultrasound. The NiO/CeO_2/ZrO_2 prepared by the surfactant-assisted co-precipitation was the most active catalyst for CO methanation. It gave 50 % CO conversion to …
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
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.
Catalytic Conversion Of Carbon Dioxide Into Cyclic Carbonates By Cu(Ii) And Ni(Ii) Acetylacetonates Anchored Onto Siral 80, Senem Coşkun, Zeynep Taşci, Mahmut Ulusoy, Mürüvvet Yurdakoç
Catalytic Conversion Of Carbon Dioxide Into Cyclic Carbonates By Cu(Ii) And Ni(Ii) Acetylacetonates Anchored Onto Siral 80, Senem Coşkun, Zeynep Taşci, Mahmut Ulusoy, Mürüvvet Yurdakoç
Turkish Journal of Chemistry
Ni and Cu acetylacetonates were anchored onto Siral 80 and used in the catalytic conversion of carbon dioxide. The catalysts were characterized by several methods such as XRD, FTIR, SEM, and TGA/DTG. The catalytic domains of the prepared heterogeneous complexes and their homogeneous counterparts were examined for the conversion reaction of carbon dioxide into cyclic carbonates in the presence of different additives (1.5 MPa CO_2 pressure, 100 ^°C, and 2 h). Good to excellent conversions were observed using Siral 80/APTES/Cu(acac)_2 catalysts and butylmethylimidazolium hexafluorophosphate, [bmim]PF_6, ionic liquid from the reaction of CO_2, and different epoxides. Modification with APTES made the …