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Full-Text Articles in Chemistry

A New Series Of Cu(Ii) And Ni(Ii) Complexes Of No Bidentate 4-No$_{2}$-Benzoylhydrazones: Synthesis, Characterization, And Biological Studies, Hati̇ce Başpinar Küçük, Emel Mataraci Kara, Berna Özbek Çeli̇k Jan 2015

A New Series Of Cu(Ii) And Ni(Ii) Complexes Of No Bidentate 4-No$_{2}$-Benzoylhydrazones: Synthesis, Characterization, And Biological Studies, Hati̇ce Başpinar Küçük, Emel Mataraci Kara, Berna Özbek Çeli̇k

Turkish Journal of Chemistry

A series of new nickel(II) and copper(II) hydrazone complexes \textbf{1--14}, containing a bidentate NO-donor hydrazone ligand, derived from 4-nitrobenzoylhydrazide and several aliphatic and aromatic aldehydes were synthesized, and their chemical structures were confirmed by means of FT-IR, UV-Vis, $^{1}$H and $^{13}$C NMR, mass spectral data, conductance measurements, and elemental analyses. The spectral data of the newly synthesized complexes show the formation of a 1:2 [metal:ligand] ratio. The ligands and their complexes were also investigated for their possible in vitro antimicrobial activities against \textit{S. aureus}, \textit{S. epidermidis}, \textit{E. coli}, \textit{K. pneumonia}, \textit{P. aeruginosa}, \textit{P. mirabilis}, \textit{E. faecalis}, and \textit{C. albicans}. Among …


Effective Recognition Of Multiple Anions By An Azobenzene--Al$^{\Mathbf{3+}}$ System, Ye Zhang, Ping Jia, Zhangfa Tong, Hai-Bo Liu, Jing Wang Jan 2015

Effective Recognition Of Multiple Anions By An Azobenzene--Al$^{\Mathbf{3+}}$ System, Ye Zhang, Ping Jia, Zhangfa Tong, Hai-Bo Liu, Jing Wang

Turkish Journal of Chemistry

A ready-to-use multifunctional coordinative system, 2,2'-dihydroxyazobenzene --aluminum (III) (DHAB--Al$^{3+})$, was created to recognize several anions effectively through three channels, namely colorimetric detection, UV-Vis spectroscopy, and fluorescence spectroscopy. Under naked eye visualization, the H$_{2}$PO$_{4}^{-}$ can be readily distinguished from the other anions by the DHAB--Al$^{3+}$ system through a change in color from reddish-orange to light yellow. H$_{2}$PO$_{4}^{-}$ was qualitatively detected by using UV-Vis and fluorescence spectra. Differentiating SO$_{3}^{2-}$, HPO$_{4}^{2-}$, and HCO$_{3}^{-}$ anions colorimetrically is difficult; thus, CO$_{3}^{2-}$, SO$_{3}^{2-}$, HPO$_{4}^{2-}$, and HCO$_{3}^{-}$ were discriminated by adopting distinct changes in the UV-Vis spectra. CO$_{3}^{2-}$, HPO$_{4}^{2-}$, and HCO$_{3}^{-}$ were accurately quantified using fluorescence spectra. …


Synthesis, Characterization, And Electrical And Optical Properties Of Magnesium-Type Boracite, Tuğba İbroşka, Azmi̇ Seyhun Kipçak, Süreyya Aydin Yüksel, Emek Derun, Sabri̇ye Pi̇şki̇n Jan 2015

Synthesis, Characterization, And Electrical And Optical Properties Of Magnesium-Type Boracite, Tuğba İbroşka, Azmi̇ Seyhun Kipçak, Süreyya Aydin Yüksel, Emek Derun, Sabri̇ye Pi̇şki̇n

Turkish Journal of Chemistry

Synthesis of the magnesium type of the mineral boracite (Mg$_{3}$B$_{7}$O$_{13}$Cl) was studied. Several parameters affecting boracite synthesis were investigated. The raw materials selected were magnesium chloride hexahydrate (MgCl$_{2}$.6H$_{2}$O), magnesium oxide (MgO), and boron oxide (B$_{2}$O$_{3})$. Reaction temperatures were selected between 600~$^{\circ}$C and 900 $^{\circ}$C. Moreover, three different reaction times of 4, 1, and 0.5 h were studied with the determined optimum molar ratio, reaction temperature, and reaction medium. Synthesized boracite characterization analyses were done by the techniques of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscope (SEM). Reaction yields were also calculated. From the results of …


Separation And Preconcentration Of Lead(Ii), Cobalt(Ii), And Nickel(Ii) On Edta Immobilized Activated Carbon Cloth Prior To Flame Atomic Absorption Spectrometric Determination In Environmental Samples, Zeid Abdullah Alothman, Erkan Yilmaz, Mohamed Habi̇la, Mustafa Soylak Jan 2015

Separation And Preconcentration Of Lead(Ii), Cobalt(Ii), And Nickel(Ii) On Edta Immobilized Activated Carbon Cloth Prior To Flame Atomic Absorption Spectrometric Determination In Environmental Samples, Zeid Abdullah Alothman, Erkan Yilmaz, Mohamed Habi̇la, Mustafa Soylak

Turkish Journal of Chemistry

The synthesis and characterization of ethylenediaminetetraacetic acid immobilized activated carbon cloth was performed in the present work. It was used for preconcentration-separation of lead(II), cobalt(II), and nickel(II) at trace levels as an adsorbent. Factors including pH, concentration and volume of eluent, sample and eluent flow rates, sample volume, and effect of coexisting ions on the solid phase extraction of analytes were examined. The preconcentration factor was 50. The detection limits for Pb(II), Co(II), and Ni(II) were 4.39, 0.99 and 0.91 $\mu $g L$^{-1}$, respectively. The adsorption capacity for Pb(II), Co(II), and Ni(II) ions was found as 11.0, 11.2, and 10.2 …


Properties And Some In Vitro Studies Of 6-Phosphogluconate Dehydrogenase Purified From The Liver Of Chalcalburnus Tarichi, The Only Fish Living In Lake Van's Highly Alkaline Water (Ph 9.8), Muhammet Güler, Vedat Türkoğlu, Mehmet Riza Kivanç Jan 2015

Properties And Some In Vitro Studies Of 6-Phosphogluconate Dehydrogenase Purified From The Liver Of Chalcalburnus Tarichi, The Only Fish Living In Lake Van's Highly Alkaline Water (Ph 9.8), Muhammet Güler, Vedat Türkoğlu, Mehmet Riza Kivanç

Turkish Journal of Chemistry

In this study, some enzymology parameters and some antibiotics affecting the enzyme activity of 6-phosphogluconate dehydrogenase (6PGD) extracted from t the livers of fish from Lake Van (\textit{Chalcalburnus tarichi}) were investigated because it is an important enzyme-producing NADPH, a reductive power, protecting the cell against the oxidative agents by producing reduced glutathione. The crude enzyme solution was obtained by using the affinity chromatography method. The native molecular weight of the enzyme is $\sim $90,000 $\pm $ 3000 Da and it is composed of two subunits with identical molecular weights of $\sim $46,000 Da as exhibited on sodium dodecyl sulfate-polyacrylamide gel …


Green And Efficient Synthesis Of Novel Bispyrazoles Through A Tandem Knoevenagel And Michael Type Reaction Using Nanowire Zinc Oxide As A Powerful And Recyclable Catalyst, Khalil Eskandari, Bahador Karami, Saeed Khodabakhshi, Seyyed Jafar Hoseini Jan 2015

Green And Efficient Synthesis Of Novel Bispyrazoles Through A Tandem Knoevenagel And Michael Type Reaction Using Nanowire Zinc Oxide As A Powerful And Recyclable Catalyst, Khalil Eskandari, Bahador Karami, Saeed Khodabakhshi, Seyyed Jafar Hoseini

Turkish Journal of Chemistry

Zinc oxide nanowires (ZnO NWs) were prepared and characterized by scanning electron microscopy, powder X-ray diffraction, and transmission electron microscopy analyses. ZnO NWs were then employed as heterogeneous and recyclable catalyst for green synthesis of some new and known bispyrazole derivatives through a tandem Knoevenagel and Michael type addition reaction of aromatic aldehyde and pyrazolone. The synthetic method is operationally simple and affords product with high yields in short reaction times.


Corrosion Inhibition By Naturally Occurring Hibiscus Sabdariffa Plant Extract On A Mild Steel Alloy In Hcl Solution, Magda Abdo Mahmoud Ameer, Amany Mohamed Fekry Jan 2015

Corrosion Inhibition By Naturally Occurring Hibiscus Sabdariffa Plant Extract On A Mild Steel Alloy In Hcl Solution, Magda Abdo Mahmoud Ameer, Amany Mohamed Fekry

Turkish Journal of Chemistry

The corrosion inhibition of mild steel alloys is of tremendous technological importance due to their increased industrial applications. Potentiodynamic polarization and electrochemical impedance spectroscopy techniques were used to establish the effect of different concentrations of HCl on the corrosion behavior of mild steel. A study was conducted on the inhibition of dissolution for a mild steel alloy in the most corrosive concentration of HCl (5 M) by adding different concentrations of aqueous extract of \textit{Hibiscus sabdariffa} plant (named karkade or rosselle) as an ecofriendly inhibitor. The extent of corrosion inhibition as measured by the two techniques was comparable. The results …


Cross Coupling Reactions Catalyzed By (Nhc)Pd(Ii) Complexes, Nevi̇n Gürbüz, Emi̇ne Özge Karaca, İsmai̇l Özdemi̇r, Beki̇r Çeti̇nkaya Jan 2015

Cross Coupling Reactions Catalyzed By (Nhc)Pd(Ii) Complexes, Nevi̇n Gürbüz, Emi̇ne Özge Karaca, İsmai̇l Özdemi̇r, Beki̇r Çeti̇nkaya

Turkish Journal of Chemistry

This review is focused on new developments reported during the last 3 years concerning the catalytic performances of in situ formed or preformed NHC--Pd(II) complexes (NHC: $N$-heterocyclic carbene) for cross-coupling reactions such as Heck--Mizoraki (often shortened to the Heck reaction), Kumada, Negishi, Suzuki--Miyaura (often shortened to the Suzuki reaction), Sonogashira and Hiyama couplings, and the Buchwald--Hartwig aminations, which are extremely powerful in the formation of C--C and C--heteroatom bonds. Due to the great number of publications and limited space here, we made a special attempt to compile the relevant data in tables, which we hope will serve as a guide …


Immobilized Metal Ion Affinity Nanospheres For \Alpha-Amylase Immobilization, Tülden Kalburcu, Müni̇re Nalan Tüzmen, Si̇nan Akgöl, Adi̇l Deni̇zli̇ Jan 2014

Immobilized Metal Ion Affinity Nanospheres For \Alpha-Amylase Immobilization, Tülden Kalburcu, Müni̇re Nalan Tüzmen, Si̇nan Akgöl, Adi̇l Deni̇zli̇

Turkish Journal of Chemistry

Immobilized metal chelate affinity chromatography (IMAC) support was practiced for \alpha-amylase immobilization. Poly(hydroxyethylmethacrylate-methacryloylamidotryptophan)-Ni^{2+} [p(HEMA-MAT)-Ni^{2+}] nanospheres, average diameter 100 nm, were produced by surfactant free emulsion polymerization. Characterizations of p(HEMA-MAT)-Ni^{2+} nanospheres were carried out by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscope (SEM). In addition, average particle size, size distribution, and surface charge were specified. The amount of N-methacryloylamidotryptophan (MAT) incorporated to polymer was determined as 1.95 mmol/g polymers by using nitrogen stoichiometry. The specific surface areas of poly(hydroxyethylmethacrylate) [p(HEMA)] and p(HEMA-MAT) nanospheres were calculated as 1856 m^2/g and 1914 m^2/g, respectively. Protein adsorption increased with increasing initial protein …


Hard Chromium Electrodeposition From A Trivalent Chromium Bath Containing Water-Soluble Polymer, Vyacheslav Protsenko, Viktor Gordiienko, Tatiana Butyrina, Elena Vasileva, Felix Danilov Jan 2014

Hard Chromium Electrodeposition From A Trivalent Chromium Bath Containing Water-Soluble Polymer, Vyacheslav Protsenko, Viktor Gordiienko, Tatiana Butyrina, Elena Vasileva, Felix Danilov

Turkish Journal of Chemistry

The effect of polyvinylpyrrolidones (PVPs) with different molecular weights as polymeric additives to a sulfate trivalent chromium bath was ascertained. Introduction of PVPs to the plating bath was stated to result in improvement in the surface appearance of chromium deposits and stabilization of current efficiency value in long-term electrolysis. The rate of metal deposition is practically independent of the deposition time. Thus, using PVP additive allows one to obtain high-quality Cr-coatings with a thickness of several tens of micrometers. It is found by means of turbidimetric analysis that the polymer additive has an accelerating effect on the aggregation of particles …


A New And Simple Dp Polarographic Method For The Determination Of Uric Acid In Serum After Elimination Of The Interference Of Ascorbic Acid And Dopamine, Ali̇ Cengi̇z Çalişkan, Güler Somer Jan 2014

A New And Simple Dp Polarographic Method For The Determination Of Uric Acid In Serum After Elimination Of The Interference Of Ascorbic Acid And Dopamine, Ali̇ Cengi̇z Çalişkan, Güler Somer

Turkish Journal of Chemistry

Determination of trace amounts of uric acid (UA) in serum is of great importance since its level in serum may show disorders in purine metabolism. With this method, trace amounts of UA in blood serum can be determined by a fast and simple procedure using differential pulse polarography (DPP). The limit of detection was estimated to be 2 \times 10^{-7} M (S/N = 3), lower than that given in previous studies. Among the many electrolytes studied, the best electrolyte condition was found to be 0.05 M phosphate buffer, pH 10--12, in 0.1 M KNO_3. The peak for UA appeared at …


A Combined First Principles Tddft And Experimental Study On The Uv-Vis Spectra Properties Of M(P-Nitrophenyl Azo Resorcinol)_3 Complexes (M: Fe, Cr), Tuğba Ari̇fi̇oğlu, Meli̇s Efeçinar, Nuray Şatiroğlu Jan 2014

A Combined First Principles Tddft And Experimental Study On The Uv-Vis Spectra Properties Of M(P-Nitrophenyl Azo Resorcinol)_3 Complexes (M: Fe, Cr), Tuğba Ari̇fi̇oğlu, Meli̇s Efeçinar, Nuray Şatiroğlu

Turkish Journal of Chemistry

UV-Vis absorption data of p-nitrophenyl azo resorcinol (Magneson I) and its 2 Fe(III) and Cr(III) complexes were investigated both experimentally and theoretically. The geometries were optimized at BP86/TZVP level. The most stable spin states were computed as doublet and quartet for Fe(magneson)_3 and Cr(magneson)_3 complexes, respectively. Time-dependent density functional theory (TDDFT) was employed to explore the absorption spectra properties, whereas the solvent effects were taken into account using the polarizable continuum model (PCM). The M06, B3LYP, and PBE0 hybrid functionals together with TZVP/LANL2TZ basis sets were used for comparing the results with experimental data. The theoretical analysis of electronic structure …


Experimental Investigation Of Drag Reduction Effects Of Polymer Additives On Turbulent Pipe Flow Using Ultrasound Doppler Velocimetry, Şeri̇fe Zeybek Vural, Göknur Bayram, Yusuf Uludağ Jan 2014

Experimental Investigation Of Drag Reduction Effects Of Polymer Additives On Turbulent Pipe Flow Using Ultrasound Doppler Velocimetry, Şeri̇fe Zeybek Vural, Göknur Bayram, Yusuf Uludağ

Turkish Journal of Chemistry

Drag reduction in fully developed turbulent pipe flow with 4 concentrations (200 to 500 wppm or mg/kg) of low molecular weight sodium carboxymethylcellulose (CMC) in aqueous solutions was investigated experimentally. Drag reduction was determined by pressure drop measurements. Maximum drag reduction achieved was 22% using 500 wppm CMC solution. To observe the impact of the presence of CMC on the flow, ultrasound Doppler velocimetry (UDV) was employed to monitor the instantaneous velocity distributions. Experimental measurements were used to calculate Fanning friction factor and radial distributions of the axial time-averaged velocity, velocity fluctuation (turbulent intensity), and eddy viscosity. Two impacts of …


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.


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.


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 …


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 Jan 2014

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 …


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 Jan 2014

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 …


Synthesis Of Novel Imidazo[1,2-A]Pyridines And Evaluation Of Their Antifungal Activities, Füsun Göktaş, Nesri̇n Cesur, Di̇lek Şatana, Meltem Uzun Jan 2014

Synthesis Of Novel Imidazo[1,2-A]Pyridines And Evaluation Of Their Antifungal Activities, Füsun Göktaş, Nesri̇n Cesur, Di̇lek Şatana, Meltem Uzun

Turkish Journal of Chemistry

New 2-(imidazo[1,2-a]pyridin-2-ylcarbonyl)-N-substituted hydrazinecarbothioamides (4a--j), N'-(3-substituted-4-oxo-1,3-thiazolidin-2-ylidene)imidazo[1,2-a]pyridine-2-carbohydrazides (5a--f), and N-(nonsubstituted/4-substituted phenyl)-5-(imidazo[1,2-a]pyridine-2-yl)-1,3,4-oxadiazole-2-amines (6a--d) were synthesized from imidazo[1,2-a]pyridine-2-carbohydrazide (3) and evaluated for antifungal activity against Microsporum gypseum NCPF 580, M. canis, Trichophyton tonsurans NCPF 245, T. rubrum, Candida albicans ATCC 10231, and C. parapsilosis ATCC 22019 using amphotericin B as the standard. The chemical structures of the compounds were confirmed by elemental analysis, IR, ^1H NMR, ^{13}C NMR, HMBC (^{13}C, ^1H), and mass spectra. Most of the tested compounds showed moderate antifungal activity. Hydrazinecarbothioamide derivatives 4h and 4f exhibited the highest activity against M. canis (MIC: 2 \mu g mL^{-1} and 4 \mu g …


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.


Convenient Synthesis Of New Polysubstituted Isoindole-1,3-Dione Analogues, Ayşe Tan, Mustafa Zahri̇tti̇n Kazancioğlu, Derya Aktaş, Özlem Gündoğdu, Ertan Şahi̇n, Nurhan Ki̇shali, Yunus Kara Jan 2014

Convenient Synthesis Of New Polysubstituted Isoindole-1,3-Dione Analogues, Ayşe Tan, Mustafa Zahri̇tti̇n Kazancioğlu, Derya Aktaş, Özlem Gündoğdu, Ertan Şahi̇n, Nurhan Ki̇shali, Yunus Kara

Turkish Journal of Chemistry

Three new polysubstituted isoindole-1,3-diones were prepared from 2-ethyl-5-hydroxy-3a,4,5,7a-tetrahydro-isoindole-1,3-dione. The reaction of 2-ethyl-5-hydroxy-3a,4,5,7a-tetrahydro-isoindole-1,3-dione with m-CPBA gave the corresponding epoxide. The triacetate derivative was obtained via cis-hydroxylation using OsO_4, followed by acetylation. An aromatic derivative, a secondary reaction product, was also formed during the acetylation. Finally, a tricyclic derivative from 2-ethyl-5-hydroxy-3a,4,5,7a-tetrahydro-isoindole-1,3-dione was synthesized via dichloroketene addition under microwave irradiation. The exact structures of epoxide and tricyclic derivatives were determined by X-ray diffraction analysis.


Thermal Conversion Of Glycerol To Value-Added Chemicals: Pyridine Derivatives By One-Pot Microwave-Assisted Synthesis, Duygu Bayramoğlu, Gökay Gürel, Ali̇ Sinağ, Mustafa Güllü Jan 2014

Thermal Conversion Of Glycerol To Value-Added Chemicals: Pyridine Derivatives By One-Pot Microwave-Assisted Synthesis, Duygu Bayramoğlu, Gökay Gürel, Ali̇ Sinağ, Mustafa Güllü

Turkish Journal of Chemistry

One-pot syntheses of the value-added heterocyclic compounds 3-methylpyridine and pyridine using a renewable chemical, glycerol, were achieved in acidic medium by thermal conversion reactions. Condensation/cyclization reactions of the thermal degradation products of glycerol were investigated in situ using different ammonia and acidic moiety producing inorganic ammonium salts under pyrolysis or microwave heating conditions. The reaction parameters were studied in detail and satisfying product yields up to 72 % were obtained under optimized conditions. Structural identification of all compounds was accomplished by spectroscopic methods.


Binding Of Flavanone With \Beta-Cd/Ctdna: A Spectroscopic Investigation, Chandrasekaran Sowrirajan, Sameena Yousuf, Muthu Vijayan Enoch Israel Vijayaraj Jan 2014

Binding Of Flavanone With \Beta-Cd/Ctdna: A Spectroscopic Investigation, Chandrasekaran Sowrirajan, Sameena Yousuf, Muthu Vijayan Enoch Israel Vijayaraj

Turkish Journal of Chemistry

The inclusion complexation of flavanone with \beta-cyclodextrin was studied by ultraviolet absorption, steady state fluorescence, time-resolved fluorescence, and 2D ROESY nuclear magnetic resonance spectroscopic techniques. A 1:1 stoichiometric ratio was determined for the inclusion of flavanone with \beta-cyclodextrin. The Stern--Volmer constant for the accessible fraction of the binding of flavanone with \beta-cyclodextrin, and the binding constant for the flavanone--\beta-cyclodextrin complex are reported. The flavanone--\beta-cyclodextrin inclusion complex was characterized by 2D ROESY NMR spectroscopy. The binding of flavanone with ctDNA and the effect of \beta-cyclodextrin on the binding of flavanone to ctDNA were studied by absorption and fluorescence techniques. Binding constants …


Simultaneous Determination Of Dexpanthenol, Lidocaine Hydrochloride, And Mepyramine Maleate In Combined Pharmaceutical Gel By Capillary Electrophoresis, Gülden Akyil, Hayri̇ye Eda Şatana Kara, Sezen Yarimkaya Baş, Nusret Ertaş, Ni̇lgün Günden Göğer Jan 2014

Simultaneous Determination Of Dexpanthenol, Lidocaine Hydrochloride, And Mepyramine Maleate In Combined Pharmaceutical Gel By Capillary Electrophoresis, Gülden Akyil, Hayri̇ye Eda Şatana Kara, Sezen Yarimkaya Baş, Nusret Ertaş, Ni̇lgün Günden Göğer

Turkish Journal of Chemistry

A new capillary electrophoresis method was developed for the simultaneous determination of dexpanthenol (DEX), lidocaine (LID), and mepyramine (MEP) in pharmaceutical preparations. The best results were obtained using 20 mM (pH 3.0) phosphate buffer as the background electrolyte. Separation was obtained using a fused-silica capillary (75 \mu m internal diameter, 50 cm total length, 41 cm effective length) and a potential of +30 kV at 20 °C. Standards and samples were injected using a pressure injection at 50 mbar for 5 s and the analytes were monitored at a detection wavelength of 200 nm. Under optimum conditions, migration times were …


Ultrarapid Catalytic Reduction Of Some Dyes By Reusable Novel Erythromycin-Derived Silver Nanoparticles, Yasmeen Junejo, Abdulhadi̇ Baykal Jan 2014

Ultrarapid Catalytic Reduction Of Some Dyes By Reusable Novel Erythromycin-Derived Silver Nanoparticles, Yasmeen Junejo, Abdulhadi̇ Baykal

Turkish Journal of Chemistry

A novel green approach for the synthesis of silver nanoparticles using erythromycin as a reducing/capping agent is presented. Erythromycin-derived silver nanoparticles were characterized by ultraviolet-visible spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy, X-ray powder diffraction, and Fourier transform infrared spectroscopy. Monodispersed silver nanoparticles showed excellent and promising catalytic activity for reduction of 3 differently charged dyes (eosin B, methylene blue, and rose bengal) in the presence of NaBH_4. The study revealed that 100% reduction of these dyes can be achieved efficiently in just 150--250 s. They were easily recovered from the reaction medium and were reused 5 times, …


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 …


Rosmarinic Acid: A Potent Carbonic Anhydrase Isoenzymes Inhibitor, Meryem Topal, İlhami̇ Gülçi̇n Jan 2014

Rosmarinic Acid: A Potent Carbonic Anhydrase Isoenzymes Inhibitor, Meryem Topal, İlhami̇ Gülçi̇n

Turkish Journal of Chemistry

Rosmarinic acid is a water-soluble ester of caffeic acid and 3,4-dihydroxyphenyllactic acids, and is mainly found in plant species including Boraginaceae and Lamiaceae. In this research, we determined the inhibition property of rosmarinic acid on carbonic anhydrase isoenzymes I and II (hCA I and II) purified from human erythrocytes by using Sepharose-4B affinity column chromatography. hCA I and II isoenzymes were obtained with a yield of 57.9% and 67.2% and 76.5- and 509.3-fold purification of each isoenzyme, respectively. In order to show the purity of the isoenzymes, SDS-PAGE was performed and one band was observed. In vitro inhibition of both …


Electrochemistry Of Fe(Iv) And Mn(Iv) Corroles Containing Meso-Dichlorophenyl Substituents And The Use Of These Compounds As Catalysts For The Electroreduction Of Dioxygen In Acid Media, Lina Ye, Zhongping Ou, Deying Meng, Mingzhu Yuan, Yuanyuan Fang, Karl M. Kadish Jan 2014

Electrochemistry Of Fe(Iv) And Mn(Iv) Corroles Containing Meso-Dichlorophenyl Substituents And The Use Of These Compounds As Catalysts For The Electroreduction Of Dioxygen In Acid Media, Lina Ye, Zhongping Ou, Deying Meng, Mingzhu Yuan, Yuanyuan Fang, Karl M. Kadish

Turkish Journal of Chemistry

Two meso-dichlorophenyl substituted metallocorroles were synthesized and characterized as to their electrochemical and spectroelectrochemical properties in dichloromethane, benzonitrile, and pyridine containing 0.1 M tetra-n-butylammonium perchlorate (TBAP) as supporting electrolyte. The examined compounds are represented as (Cl_2Ph)_3CorFe^{IV}Cl and (Cl_2Ph)_3CorMn^{IV}Cl where (Cl_2Ph)_3Cor is the trianion of 5,10,15-tri(2,4-dichlorophenyl)corrole. Each metallocorrole was examined as to its catalytic activity for the electoreduction of dioxygen when coated on an edge-plane pyrolytic graphite electrode in 1.0 M HClO_4. Cyclic voltammetry combined with linear sweep voltammetry at a rotating disk electrode (RDE) and a rotating ring disk electrode (RRDE) was utilized to evaluate the catalytic activity for the …


Td-Dft Calculations And Mcd Spectroscopy Of Porphyrin And Phthalocyanine Analogues: Rational Design Of Photosensitizers For Pdt And Nir Region Sensor Applications, John Mack, Martijn Wildervanck, Tebello Nyokong Jan 2014

Td-Dft Calculations And Mcd Spectroscopy Of Porphyrin And Phthalocyanine Analogues: Rational Design Of Photosensitizers For Pdt And Nir Region Sensor Applications, John Mack, Martijn Wildervanck, Tebello Nyokong

Turkish Journal of Chemistry

Geometry optimizations and TD-DFT calculations have been carried out on series of fused-ring-expanded phthalonitriles, phthalocyanines, and aza-dipyrromethene boron difluoride (aza-BODIPY) dyes and trends in their optical and redox properties have been analyzed. The potential utility of fused-ring-expanded phthalocyanine and aza-BODIPY analogues for photodynamic therapy and near infrared region sensor applications is assessed on this basis. Recent attempts to prepare fused-ring-expanded aza-BODIPY analogues with benzene, pyrazine, and naphthalene rings have demonstrated that the properties of aza-BODIPYs vary markedly when different fused ring systems are added to the \beta-carbons of the pyrrole rings. A comparison of the TD-DFT calculations demonstrates that, as …


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 …