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2013

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Articles 991 - 1020 of 1354

Full-Text Articles in Chemistry

C_2-Symmetric Chiral Diamine Ligands For Enantiomeric Recognition Of Amino Acid Esters And Mandelic Acid By Proton Nmr Titration Method, Hayri̇ye Aral, Tarik Aral, Mehmet Çolak, Berri̇n Zi̇yadanoğullari, Recep Zi̇yadanoğullari Jan 2013

C_2-Symmetric Chiral Diamine Ligands For Enantiomeric Recognition Of Amino Acid Esters And Mandelic Acid By Proton Nmr Titration Method, Hayri̇ye Aral, Tarik Aral, Mehmet Çolak, Berri̇n Zi̇yadanoğullari, Recep Zi̇yadanoğullari

Turkish Journal of Chemistry

Two novel C_2-symmetric chiral diamines containing \alpha -phenylethyl and \alpha -(1-naphthyl)ethyl chiral subunits were prepared with quantitative yields. Enantiomeric recognition properties of these simple structured diamine ligands towards D- and L-amino acid esters and D- and L-mandelic acid were examined by the ^1H NMR titration method. These ligands exhibited strong complexation (with K_f up to 2481 M^{-1}) and good enantioselectivity (up to K_L/K_D = 4.08) towards the mandelic acid enantiomers. The results show that simple structured and easily accessible acyclic C_2-symmetrical compounds can also be used for enantiomeric recognition of racemic amino acids and mandelic acid in addition to complex …

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Theoretical Study On The Addition Reaction Between Propadienylidene And Methyleneimine, Mengyuan Wang, Yungang Chen, Shanshan Ding, Yingde Wang, Qianchao Cao, Xiaojun Tan, Jinsong Gu Jan 2013

Theoretical Study On The Addition Reaction Between Propadienylidene And Methyleneimine, Mengyuan Wang, Yungang Chen, Shanshan Ding, Yingde Wang, Qianchao Cao, Xiaojun Tan, Jinsong Gu

Turkish Journal of Chemistry

The reaction mechanism between propadienylidene and methyleneimine was systematically investigated employing the second-order Møller--Plesset perturbation theory (MP2) method with the 6 -- 31 + G* basis set. Geometry optimization, vibrational analysis, and energy property of the involved stationary points on the potential energy surface were calculated. The energies of the different species were corrected by single point energy calculations at the CCSD (T) // MP2 / 6 -- 31 + G* level. From the surface energy profile, one important initial intermediate characterized by a 3-membered ring structure was located via a transition state firstly. After that, 3 different products possessing …

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Adsorption Equilibrium Of Water Vapor On Activated Carbon And Alumina And Carbon And Alumina Impregnated With Hygroscopic Salt, Ioan Solomon, Ana Mafalda Ribeiro, Joao Carlos Santos, Jose Miguel Loureiro, Alirio E. Rodrigues, Ion Sandu, Ioan Mamaliga Jan 2013

Adsorption Equilibrium Of Water Vapor On Activated Carbon And Alumina And Carbon And Alumina Impregnated With Hygroscopic Salt, Ioan Solomon, Ana Mafalda Ribeiro, Joao Carlos Santos, Jose Miguel Loureiro, Alirio E. Rodrigues, Ion Sandu, Ioan Mamaliga

Turkish Journal of Chemistry

The adsorption equilibrium of water vapor on different adsorbent materials has been studied. Small grains of commercial activated carbon and alumina, with a diameter of d_g = 1.5 \times 10^{-3} m, were impregnated with a hygroscopic salt (calcium chloride) to improve the performance of these materials. The main characteristics of the new composite materials were obtained by adsorption/desorption of nitrogen at 77 K and salt distribution on the adsorbent surface was shown using scanning electron microscopy. The adsorption equilibrium isotherms of water vapor were measured by a gravimetric system at 2 different temperatures in the case of alumina and impregnated …

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Spectral, Electrochemical, Luminescence, And Dye-Sensitized Solar Cell Studies Of Mono And D-F Hetero Binuclear Cryptates, Arunachalam Vijayaraj, Raju Prabu, Ranganathan Suresh, Subbaiah Manoharan, Sambandam Anandan, Vengidusamy Narayanan Jan 2013

Spectral, Electrochemical, Luminescence, And Dye-Sensitized Solar Cell Studies Of Mono And D-F Hetero Binuclear Cryptates, Arunachalam Vijayaraj, Raju Prabu, Ranganathan Suresh, Subbaiah Manoharan, Sambandam Anandan, Vengidusamy Narayanan

Turkish Journal of Chemistry

Mono and hetero binuclear cryptates, [Gd(III)ML]^+ [M = VO(IV), Co(II), Ni(II), Cu(II)], were synthesized by a 2-step method. The ligand L represents the deprotonated anionic cryptate obtained by the 2+3 condensation of tris-(2-aminoethyl)amine with 2,6-diformyl-4-nitrophenol. The complexes were characterized by elemental analysis, spectral, magnetic, and electrochemical studies. Fluorescence of Gd(III) ion in the cavity was quenched by the encapsulated Cu(II) and Ni(II) ions. [GdCoL(NO_3)]^+ cryptate had a high lifetime value compared to other cryptates. The cyclic voltammogram showed that the reduction potential values of [Gd(M)L] M = VO(IV), Co(II), Ni(II), and Cu(II) complexes were in the following order: Cu(II) > Ni(II) …

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Establishment Of An Electrochemical Rna Aptamer-Based Biosensor To Trace Nanomolar Concentrations Of Codeine, Mehdi Saberian, Davoud Asgari, Yadollah Omidi, Jaleh Barar, Hossein Hamzeiy Jan 2013

Establishment Of An Electrochemical Rna Aptamer-Based Biosensor To Trace Nanomolar Concentrations Of Codeine, Mehdi Saberian, Davoud Asgari, Yadollah Omidi, Jaleh Barar, Hossein Hamzeiy

Turkish Journal of Chemistry

Codeine is an opium alkaloid with a great potential of abuse among opioid consumers. Detection of codeine is a routine procedure in the military and government of some countries for personnel recruitment. Therefore, a specific, selective, and easy to use method would be an important improvement in such detection procedures. According to previous reports, short single-stranded DNA or RNA sequences with high affinity and specificity to their targets, aptamers, could be used for designing an accurate and specific biosensor for codeine. This study introduces an aptamer-based biosensor for codeine detection in nanomolar concentrations by an electrochemical method, and ferrocene carboxylic …

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Potentiometric Study Of Equilibrium Constants Of A Novel Triazine--Thione Derivative And Its Stability Constants With Hg^{2+}, Cu^{2+}, Ni^{2+}, Pb^{2+}, And Zn^{2+} Metal Ions In Ethanol And Water Mixed, Fati̇h Polat, Hasan Atabey, Hayati̇ Sari, Alaaddi̇n Çukurovali Jan 2013

Potentiometric Study Of Equilibrium Constants Of A Novel Triazine--Thione Derivative And Its Stability Constants With Hg^{2+}, Cu^{2+}, Ni^{2+}, Pb^{2+}, And Zn^{2+} Metal Ions In Ethanol And Water Mixed, Fati̇h Polat, Hasan Atabey, Hayati̇ Sari, Alaaddi̇n Çukurovali

Turkish Journal of Chemistry

The deprotonation constants of 5-hydroxy-5,6-di-pyridin-2-yl-4,5-dihydro-2H-[1,2,4] triazine-3-thione (HPT) and the stability constants of its Hg^{2+}, Ni^{2+}, Cu^{2+}, Pb^{2+}, and Zn^{2+} ion complexes were studied in 20% ethanol and water mixed at 25 \pm 0.1 °C and ionic strength (I) of 0.1 M supported by NaCl. Four pK_a values of HPT were determined: 3.58, 6.30, 9.23, and 9.69. In various pH conditions, the different complex forms were formulated as ML, MHL, MH_2L, MH_3L, MH_4L, and MH_{-2}L between Hg^{2+}, Ni^{2+}, Cu^{2+}, Pb^{2+}, and Zn^{2+} ions and HPT. According to the potentiometric and spectrophotometric results, the HPT and Hg^{2+} combination formed a selective and …

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New Synthetic Strategy For Novel 6-Arylazo-5-Methyl-3-Aryl-Thiazolo[2,3-C]- [1,2,4]Triazoles And Study Of Their Solvatochromic Properties, Ahmad Sami Shawali, Mohie Eldin Moustafa Zayed Jan 2013

New Synthetic Strategy For Novel 6-Arylazo-5-Methyl-3-Aryl-Thiazolo[2,3-C]- [1,2,4]Triazoles And Study Of Their Solvatochromic Properties, Ahmad Sami Shawali, Mohie Eldin Moustafa Zayed

Turkish Journal of Chemistry

Two series of 6-arylazothiazol[2,3-c][1,2,4]triazoles were prepared via oxidative cyclization of the respective aldehyde N-(5-arylazo-4-methylthiazol-2-yl)-hydrazones. The structures of the latter hydrazone precursors and the azo compounds were confirmed by spectral and elemental analyses. The solvatochromism of the title azo dyes is evaluated by means of the Kamlet--Taft equation and discussed.

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Exploring Distinct Binding Site Regions Of \Beta_2-Adrenergic Receptor Via Coarse-Grained Molecular Dynamics Simulations, Si̇bel Çakan, Ebru Demet Akdoğan Jan 2013

Exploring Distinct Binding Site Regions Of \Beta_2-Adrenergic Receptor Via Coarse-Grained Molecular Dynamics Simulations, Si̇bel Çakan, Ebru Demet Akdoğan

Turkish Journal of Chemistry

\beta_2-Adrenergic receptor (\beta_2AR) is a G protein- coupled receptor that is highly flexible and able to recognize a wide range of ligands through its conformational variations. Active and inactive conformations revealed by recent crystallographic experiments do not provide a complete dynamic picture of the receptor, especially in the binding site. In this study, molecular dynamics (MD) simulation through a residue-based coarse-grained model is used as an alternative and efficient method to explore a wider conformational search space. The system was composed of \beta_2AR embedded into a 1-palmitoyl-2-oleoyl-phosphatidylcholine membrane bilayer with surrounding water. A total of 6 \mu s of simulation …

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Quasielastic Light Scattering Studies Of Polypeptides: Evidence For Chain Extension In Solution, Mehmet Bahatti̇n Baysal, Çi̇ğdem Karadağ Jan 2013

Quasielastic Light Scattering Studies Of Polypeptides: Evidence For Chain Extension In Solution, Mehmet Bahatti̇n Baysal, Çi̇ğdem Karadağ

Turkish Journal of Chemistry

Dynamic light scattering and viscosimetric methods were used to study polypeptides including polyleucine, poly (\gamma-benzyl-L-glutamate), poly (\alpha-L-glutamic acid), and polyproline II. Chain extension showing rod-like and flexible conformations occurred in poly(\gamma -benzyl-L-glutamate) and polyproline II solutions as these solutions were diluted in glacial acetic acid or in a mixed solvent of acetic acid and dichloromethane. The elongation of chains in poly(\gamma -benzyl-L-glutamate) and polyproline II solutions was studied by dynamic light scattering and viscosimetric methods. This nonenzymatic growth of peptide chains provides data on primordial synthesis of protein molecules in the absence of cell machinery and for this reason these …

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Asymmetric Synthesis Of \Alpha-(Heteroaryl)Alkylamines And \Alpha -Amino Acids Via Nucleophilic 1,2-Addition Of Lithiated Heterocycles To Aldehyde Samp-Hydrazones, Dieter Enders, Giuseppe Del Signore, Gerhard Raabe Jan 2013

Asymmetric Synthesis Of \Alpha-(Heteroaryl)Alkylamines And \Alpha -Amino Acids Via Nucleophilic 1,2-Addition Of Lithiated Heterocycles To Aldehyde Samp-Hydrazones, Dieter Enders, Giuseppe Del Signore, Gerhard Raabe

Turkish Journal of Chemistry

The asymmetric synthesis of \alpha-(heteroaryl)alkylamines was accomplished by employing a diastereoselective nucleophilic 1,2-addition of lithiated aromatic heterocycles to aldehyde SAMP-hydrazones, followed by BH_3 . THF or SmI_2 promoted removal of the chiral auxiliary. The CBz or benzoyl-protected amines were obtained in good yields (40\%--78\%) and excellent enantiomeric excesses (ee = 88\%--99\%). The methodology can be applied to the synthesis of highly enantioenriched \alpha-amino acids (ee = 90\%--99\%).

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An Amphipathic Thioxanthone-Anthracene Photoinitiator For Free-Radical Polymerization, Deni̇z Tunç Beyazit, Burçi̇n Gacal, Yusuf Yağci Jan 2013

An Amphipathic Thioxanthone-Anthracene Photoinitiator For Free-Radical Polymerization, Deni̇z Tunç Beyazit, Burçi̇n Gacal, Yusuf Yağci

Turkish Journal of Chemistry

A novel thioxanthone-anthracene (TX-A) photoinitiator possessing an octyl group, TX-A-Oct, as amphipathic photoinitiator was synthesized by click chemistry. Its ability to initiate photopolymerization of various monomers, namely methyl methacrylate (MMA), acryl amide (Am), butyl acrylate (BA), styrene (St), and a multifunctional monomer trimethylolpropane triacrylate (TMPTA), was examined in both the presence and absence of air. TX-A-Oct was found to be effective in initiating polymerization also in the absence of a co-initiator. UV, FTIR, and fluorescence spectroscopic analysis and polymerization studies revealed that depending on the conditions photoinitiations occur through both anthracene and thioxanthone chromophoric groups by hydrogen abstraction and endoperoxide …

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Photo- And Electroluminescence Behavior Of Biphenyl Containing Conjugated Polymer, Tuğba Kaya Deni̇z, Doğukan Hazar Apaydin, Ali̇ Can Özelçağlayan, Levent Kami̇l Toppare, Ali̇ Çirpan Jan 2013

Photo- And Electroluminescence Behavior Of Biphenyl Containing Conjugated Polymer, Tuğba Kaya Deni̇z, Doğukan Hazar Apaydin, Ali̇ Can Özelçağlayan, Levent Kami̇l Toppare, Ali̇ Çirpan

Turkish Journal of Chemistry

Light emitting properties of poly[4-(5-(biphenyl- 4-yl)-4-hexylthiophen-2-yl)-2-dodecyl-7-(4-hexyl-thiophen-2-yl)-2H-benzo[d][1,2,3]-triazole] (PPhHTBT) and poly(9-vinylcarbazole) (PVK) blends were investigated with a configuration of ITO/PEDOT-PSS/BLEND/Ca/Al in ratios ranging from 5 to 100 wt\% in PPhHTBT. Thin film and solution spectra of all blends revealed that energy transfer was completely achieved. Device performance increased for all blends and reached 1.1 cd/A for 30 wt\% PPhHTBT.

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Dft Study Of Tautomerism In Aklavinone, Burhan Lemi̇ Türker Jan 2013

Dft Study Of Tautomerism In Aklavinone, Burhan Lemi̇ Türker

Turkish Journal of Chemistry

Aklavinone has an anthraquinone-based chromophore and its backbone highly resembles the kernel of some anthracycline antibiotics that possess anticancer activity, e.g., daunomycin. Since aklavinone's structure possesses many --OH groups and 2 keto groups, it is quite probable that certain tautomeric equilibria may occur. Presently, aklavinone prototropic tautomers possessing embedded anthraquinone moiety have been investigated quantum chemically by using density functional theory at the levels of RB3LYP/6-31G(d) and RB3LYP/6-31G(d,p). Additionally, IR spectra of the tautomers were calculated. Moreover, the phenolate ions obtained from the most stable tautomer in water were considered, and the protonation of this tautomer at various possible sites …

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Calixarene-Based Receptors For Molecular Recognition, Mustafa Yilmaz, Serkan Erdemi̇r Jan 2013

Calixarene-Based Receptors For Molecular Recognition, Mustafa Yilmaz, Serkan Erdemi̇r

Turkish Journal of Chemistry

Calixarene-based molecular receptors have been a widely developing area in material science and technology for the last few decades. Due to their bowl-shaped geometry, calixarene macrocycles are used as hosts allowing organic and inorganic guests to coordinate/sorb onto their cavity. This work briefly reviews the recent development of calixarenes.

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Synthesis Of Fused Tetrazolone Derivatives, Sevi̇l Özcan, Zeynep Ekmekçi̇, Berk Müjde, Meti̇n Balci Jan 2013

Synthesis Of Fused Tetrazolone Derivatives, Sevi̇l Özcan, Zeynep Ekmekçi̇, Berk Müjde, Meti̇n Balci

Turkish Journal of Chemistry

New fused tetrazolone derivatives were synthesized using homophthalic and maleic anhydrides. Treatment of anhydrides with trimethylsilyl azide opened the lactone rings and formed the corresponding intermediates, which bore 1,3-dipole and dipolarophile functionalities in ortho positions. The intermediates partially underwent internal 1,3-dipolar cycloaddition to produce fused tetrazolone derivatives. When the carbonyl groups in anhydride were not conjugated with any double bond, then a triazine-fused tetrazolone derivative was formed.

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Terpenoids, Essential Oil Composition, Fatty Acid Profile, And Biological Activities Of Anatolian Salvia Fruticosa Mill., Gülaçti Topçu, Mehmet Öztürk, Tuba Kuşman, Ayşe Asli Barla Demi̇rkoz, Ufuk Kolak, Ayhan Ulubelen Jan 2013

Terpenoids, Essential Oil Composition, Fatty Acid Profile, And Biological Activities Of Anatolian Salvia Fruticosa Mill., Gülaçti Topçu, Mehmet Öztürk, Tuba Kuşman, Ayşe Asli Barla Demi̇rkoz, Ufuk Kolak, Ayhan Ulubelen

Turkish Journal of Chemistry

The hexane and dichloromethane extracts, obtained by re-extraction of the methanol extract of Salvia fruticosa Mill., afforded 7 diterpenoids (carnosol, carnosic acid, carnosic acid 12-methyl ether, rosmadial, isorosmanol, ferruginol, and manool), 4 triterpenoids (\alpha -amyryltetracosanoate, oleanolic acid, ursolic acid, and erythrodiol), a steroid (3-acetylsitosterol), and a flavone (salvigenin). The galls (apples) of the collected plant were separately extracted with hexane to afford fatty acids composed mainly of oleic acid (29\%), palmitoleic acid (29\%), and stearic acid (23.20\%), which exhibited high anticholinesterase activity, particularly against BChE. The essential oil, obtained from the aerial parts of the plant, exhibited high AChE inhibitory …

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Anticholinesterase Furocoumarins From Heracleum Platytaenium, A Species Endemic To The Ida Mountains, Demet Di̇ncel, Seda Damla Hatipoğlu, Ahmet Ceyhan Gören, Gülaçti Topçu Jan 2013

Anticholinesterase Furocoumarins From Heracleum Platytaenium, A Species Endemic To The Ida Mountains, Demet Di̇ncel, Seda Damla Hatipoğlu, Ahmet Ceyhan Gören, Gülaçti Topçu

Turkish Journal of Chemistry

The petroleum ether extract of Heracleum platytaenium afforded 8 furocoumarins (psoralen, bergapten, xanthotoxin, pimpinellin, isopimpinellin, sphondin, byakangelicin, and heraclenol) and the methanol extract of H. platytaenium gave only 1 glycosylated dihydrofurocoumarin, apterin. In addition, stigmasterol was also obtained from petroleum ether extract. Structure identification of the isolated compounds has been achieved by using spectroscopic methods, namely 1D and 2D NMR experiments and mass spectral analyses. The antioxidant activity of the extracts and pure compounds was investigated by 2 methods, including DPPH free radical scavenging activity and lipid peroxidation inhibitory activity by \beta-carotene-linoleic acid assays. The anticholinesterase activity of petroleum ether …

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Synthesis Of Novel Benzimidazole Salts And Microwave-Assisted Catalytic Activity Of In Situ Generated Pd Nanoparticles From A Catalyst System Consisting Of Benzimidazol Salt, Pd(Oac)_2, And Base In A Suzuki-Miyaura Reaction, Ülkü Yilmaz, Hasan Küçükbay, Sevi̇m Türkteki̇n Çeli̇kesi̇r, Mehmet Akkurt, Orhan Büyükgüngör Jan 2013

Synthesis Of Novel Benzimidazole Salts And Microwave-Assisted Catalytic Activity Of In Situ Generated Pd Nanoparticles From A Catalyst System Consisting Of Benzimidazol Salt, Pd(Oac)_2, And Base In A Suzuki-Miyaura Reaction, Ülkü Yilmaz, Hasan Küçükbay, Sevi̇m Türkteki̇n Çeli̇kesi̇r, Mehmet Akkurt, Orhan Büyükgüngör

Turkish Journal of Chemistry

Novel benzimidazolium salts having N-benzyl or N-(4-substitutedbenzyl) groups were synthesized and their microwave-promoted catalytic activity for the Suzuki--Miyaura cross-coupling reaction were determined using in situ formed palladium(0) nanoparticles (PdNPs) from a catalytic system consisting of Pd(OAc)_2/K2CO_3 in DMF/H_2O. PdNPs were characterized by X-ray diffraction (XRD) pattern and particle size of in situ generated PdNPs from the Pd(111) plane was determined to be of diameter 19.6 nm by the Debye--Scherrer equation. Moreover, the yield of the Suzuki--Miyaura reactions with aryl iodides and aryl bromides was found to be nearly quantitative. The synthesized benzimidazole salts (1--5) were identified by ^1H and ^{13}C …

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Optimization Of A Gas Chromatography--Mass Spectrometry Method Using Chemometric Techniques For The Determination Of Ezetimibe In Human Plasma, Ebru Uçaktürk, Nuran Özaltin Jan 2013

Optimization Of A Gas Chromatography--Mass Spectrometry Method Using Chemometric Techniques For The Determination Of Ezetimibe In Human Plasma, Ebru Uçaktürk, Nuran Özaltin

Turkish Journal of Chemistry

A new, rapid, and sensitive gas chromatography--mass spectrometry (GC-MS) method was developed for the determination of ezetimibe (EZE) in human plasma. EZE was derivatized prior to GC-MS analysis. Various derivatization techniques such as acetylation, methylation, and silylation were tried. EZE was extracted from plasma with high recovery (94.39%--97.57%) using methyl tertbutyl ether and carbonate buffer (pH 9). Chromatographic conditions were optimized using chemometric methods. In the first step, optimization with factorial design, chromatographic variables (initial and final column temperature, oven ramp rate, and flow rate of gas) were screened to select important variables for the retention of EZE. In the …

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Ultrasound-Assisted Emulsification--Solidified Floating Organic Drop Microextraction Combined With Flow Injection--Flame Atomic Absorption Spectrometry For The Determination Of Palladium In Water Samples, Shayessteh Dadfarnia, Ali Mohammad Haji Shabani, Mooud Amirkavei Jan 2013

Ultrasound-Assisted Emulsification--Solidified Floating Organic Drop Microextraction Combined With Flow Injection--Flame Atomic Absorption Spectrometry For The Determination Of Palladium In Water Samples, Shayessteh Dadfarnia, Ali Mohammad Haji Shabani, Mooud Amirkavei

Turkish Journal of Chemistry

The ultrasound-assisted emulsification--solidified floating organic drop microextraction (USAE--SFODME) methodology was combined with flow injection--lame atomic absorption spectrometry (FI--FAAS) for the separation/pre\-concentration and determination of palladium at ultratrace level. In this method, the palladium ion in the aqueous solution was complexed with acetylacetone (6 \times 10^{-3} mol L^{-1}) in the pH range of 1--7 and was extracted into 40 \mu L of 1-undecanol, which was sonically dispersed in the aqueous phase. The vial was then centrifuged and cooled in an ice bath for 5 min. The solidified extract was melted and diluted to 100 \mu L with a solution of hydrochloric …

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Poly(4-Vinylpyridine)-Supported Dual Acidic Ionic Liquid: An Environmentally Friendly Heterogeneous Catalyst For The One-Pot Synthesis Of 4,4'-(Arylmethylene)Bis(3-Methyl-1-Phenyl-1h-Pyrazol-5-Ols), Kaveh Parvanak Boroujeni, Pegah Shojaei Jan 2013

Poly(4-Vinylpyridine)-Supported Dual Acidic Ionic Liquid: An Environmentally Friendly Heterogeneous Catalyst For The One-Pot Synthesis Of 4,4'-(Arylmethylene)Bis(3-Methyl-1-Phenyl-1h-Pyrazol-5-Ols), Kaveh Parvanak Boroujeni, Pegah Shojaei

Turkish Journal of Chemistry

A poly(4-vinylpyridine)-supported Brønsted ionic liquid was easily prepared from its starting materials and used as a novel, highly efficient, and reusable heterogeneous catalytic system for the synthesis of 4,4'-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ols) from the condensation reaction between aromatic aldehydes and 2 equivalents of 3-methyl-l-phenyl-5-pyrazolone.

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Optimization Of Synthesizing Glucose 1-Phosphate By Sodium Tripolyphosphate As A Phosphorus Acylating Agent Using Response Surface Methodology, Li 'E Jin, Fenfen Chang, Xiao Juan Wang, Qing Cao Jan 2013

Optimization Of Synthesizing Glucose 1-Phosphate By Sodium Tripolyphosphate As A Phosphorus Acylating Agent Using Response Surface Methodology, Li 'E Jin, Fenfen Chang, Xiao Juan Wang, Qing Cao

Turkish Journal of Chemistry

With glucose as the starting material, sodium tripolyphosphate as the phosphorus acylating agent, and urea as the catalyst, glucose 1-phosphate was synthesized and its properties were analyzed. The synthesis conditions were selected according to the phosphorus content and optimized through the response surface methodology (RSM), based on a 3-level, 3-variable Box--Behnken experimental design. The results showed that the phosphorus content of glucose 1-phosphate was 8.12% using a reaction temperature of 70 °C, a molar ratio of glucose to sodium tripolyphosphate of 1.54:1, and catalyst amount of 3.7 g. It coincided well with the experimental value (8.34%). The structure of the …

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Synthesis Of 3,4-Diaryl-1-Phenyl-4,5-Dihydro-1h-Pyrazole-5-Carbonitriles Via 1,3-Dipolar Cycloaddition Reactions, Jayaroopa Prabhashankar, Vasanth Kumar Govindappa, Ajay Kumar Kariyappa Jan 2013

Synthesis Of 3,4-Diaryl-1-Phenyl-4,5-Dihydro-1h-Pyrazole-5-Carbonitriles Via 1,3-Dipolar Cycloaddition Reactions, Jayaroopa Prabhashankar, Vasanth Kumar Govindappa, Ajay Kumar Kariyappa

Turkish Journal of Chemistry

Nitrile imines generated by the oxidative dehydrogenation of aromatic aldehyde phenylhydrazones with chloramine-T as a catalytic dehydrogenating agent were trapped in situ by 4-methoxy cinnamonitrile to afford 3,4-diaryl-1-phenyl-4,5-dihydro-1H-pyrazole-5-carbonitrile in moderate to good yields. The structures of the cycloadducts were confirmed by spectral studies and elemental analysis.

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Biodegradability Of Degradable Mulching Film In A Laboratory-Controlled Composting Test, Xuemei Zhang, Yaxi Huang, Deqiang Li, Zicheng Wen, Baoxun Sui, Zhiyong Liu Jan 2013

Biodegradability Of Degradable Mulching Film In A Laboratory-Controlled Composting Test, Xuemei Zhang, Yaxi Huang, Deqiang Li, Zicheng Wen, Baoxun Sui, Zhiyong Liu

Turkish Journal of Chemistry

A series of degradable films was prepared, and 2 formulas of polyethylene (PE) films with the highest degradable performance were experimentally determined. These films contained 3.43% and 0.44% stearate, and were denoted as PE-3 and PE-4, respectively. Their biodegradability was studied in a laboratory-controlled composting test using ordinary PE film (OPEF) as a control. Contrast composting experiments indicated that the biodegradability of untreated samples was very low, and that the biodegradation rates of PE films after natural aging were significantly higher. FT-IR analysis showed that OPEF changed little after the composting experiment, and that PE-3 and PE-4 showed a carbonyl …

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Synthesis, Characterization, And Dft Calculation Of A Pd(Ii) Schiff Base Complex, Alireza Akbari, Zahra Alinia Jan 2013

Synthesis, Characterization, And Dft Calculation Of A Pd(Ii) Schiff Base Complex, Alireza Akbari, Zahra Alinia

Turkish Journal of Chemistry

The 4-((E)-(2-((E)-2, 4-dihydroxybenzylideneamino) ethylimino) methyl) benzene-1,3-diol tetradentate ligand, H_2L, reacted with PdCl_2 to produce the related complex. The complex was characterized by elemental analysis, infrared and electronic spectroscopy, thermogravimetric study, and molar conductance. Furthermore, the fully optimized geometries were calculated using the ADF 2009.01 package. Comparison between the calculated and experimental results covering molecular structures, assignment of fundamental vibrational modes, and thermodynamic properties were investigated. The optimized molecular geometries were compared with the experimental data obtained from X-ray data of a similar complex, which indicated that the theoretical results agree with the corresponding experimental values. The UV-Vis spectrum of the …

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Synthesis Of Tetrakis(Carboxyphenyl)Porphyrin Coated Paramagnetic Iron Oxide Nanoparticles Via Amino Acid For Photodegradation Of Methylene Blue, Rahmatollah Rahimi, Azadeh Tadjarodi, Mina Imani, Mahboubeh Rabbani, Samaneh Safalou Moghaddam, Hamed Kerdari Jan 2013

Synthesis Of Tetrakis(Carboxyphenyl)Porphyrin Coated Paramagnetic Iron Oxide Nanoparticles Via Amino Acid For Photodegradation Of Methylene Blue, Rahmatollah Rahimi, Azadeh Tadjarodi, Mina Imani, Mahboubeh Rabbani, Samaneh Safalou Moghaddam, Hamed Kerdari

Turkish Journal of Chemistry

In this paper, synthesis of tetrakis(carboxyphenyl)porphyrin (TCPP) coated cadmium ferrite (CdFe_2O_4) nanoparticles by using L-lysine as an anchor is reported for the first time. The ferrimagnetic CdFe_2O_4 nanoparticles were prepared via the facile self-assembly method of reflux followed by a heating treatment. The obtained magnetic nanoparticles were coated with TCPP in the presence of the amino acid L-lysine by sonication in ethanol and then refluxing for 12 h. The structural characteristics of the products were determined using FT-IR and XRD pattern. Scanning electron microscopy (SEM) images indicated uniform morphologies of the magnetic nanoparticles with an average size of 43 nm. …

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Synthesis Of New N-[3-(Benzo[D]Thiazol-2-Yl)-4-Methylthiazol-2(3h)-Ylidene] Substituted Benzamides, Aamer Saeed, Hummera Rafique Jan 2013

Synthesis Of New N-[3-(Benzo[D]Thiazol-2-Yl)-4-Methylthiazol-2(3h)-Ylidene] Substituted Benzamides, Aamer Saeed, Hummera Rafique

Turkish Journal of Chemistry

A series of novel N-[3-(2-benzo[d]thiazol-2-yl)-4-methylthiazol-2(3H)-ylidene] substituted benzamides (2a--k) were efficiently synthesized by heterocyclization of the corresponding 1-(benzo[d]thiazol-2-yl)-3-aroylthioureas (1a--k). The cyclization was achieved by the reaction of \alpha-bromoacteone produced in situ using bromine in dry acetone in the presence of triethylamine.

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Sesquiterpene Hydrocarbons Of The Essential Oil Of Actinolema Macrolema Boiss, Betül Demi̇rci̇, Gülden Koltuksuz Yasdikcioğlu, Kemal Hüsnü Can Başer Jan 2013

Sesquiterpene Hydrocarbons Of The Essential Oil Of Actinolema Macrolema Boiss, Betül Demi̇rci̇, Gülden Koltuksuz Yasdikcioğlu, Kemal Hüsnü Can Başer

Turkish Journal of Chemistry

The essential oils of Actinolema macrolema Boiss. (Apiaceae) were obtained by hydrodistillation in the first 3 (sample A) and the following 3 h (sample B) from crushed fruits and dried leaves (sample C), which were subsequently analyzed by GC and GC-MS. Overall, 64 components were characterized, representing 93% of the leaf oil. Thirty components were characterized from the fruit oil representing 95% of the first fraction and 90% of the second fraction consecutively. Guaia-5,7(11)-diene, selina-3,7(11)-diene, and juniper camphor were isolated from the oils by column chromatography and their structures were elucidated by GC-MS, ^1H NMR, and ^{13}C NMR. The occurrence …

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Comparative Study Of Microwave-Assisted And Conventional Synthesis Of Ibuprofen-Based Acyl Hydrazone Derivatives, Ayşe Uzgören Baran Jan 2013

Comparative Study Of Microwave-Assisted And Conventional Synthesis Of Ibuprofen-Based Acyl Hydrazone Derivatives, Ayşe Uzgören Baran

Turkish Journal of Chemistry

A series of potential biological active acyl hydrazone derivatives containing ibuprofen moiety (compounds 4a--4p) was synthesized by the condensation of ibuprofen hydrazone with aromatic aldehydes using conventional and microwave irradiation methods. The microwave method was found to be successful with nearly the same or higher yields and shorter reaction time, and it was more environmentally friendly compared to the conventional heating method. The chemical structures of the synthesized compounds were characterized by IR, ^1H NMR, and APT-NMR spectroscopy.

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Asymmetric Henry Reaction Catalyzed By Cu(I)-Based Chiral Amino Alcohol Complex, Tianhua Shen, Quan Qin, Hang Ni, Ting Xia, Xiaocong Zhou, Funa Cui, Junqi Li, Deqiang Ran, Qingbao Song Jan 2013

Asymmetric Henry Reaction Catalyzed By Cu(I)-Based Chiral Amino Alcohol Complex, Tianhua Shen, Quan Qin, Hang Ni, Ting Xia, Xiaocong Zhou, Funa Cui, Junqi Li, Deqiang Ran, Qingbao Song

Turkish Journal of Chemistry

The Cu(I)-based complex prepared from (S)-2-(furan-2-yl-methylamino)-2-phenylethanol (5c) and CuCl was used as catalyst in enantioselective Henry reactions of arylaldehydes and nitromethane, which gave 89% ee and 95% yield at ambient temperature. The proposed catalytic cycle of an asymmetric Henry reaction was suggested.

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