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Full-Text Articles in Physical Sciences and Mathematics

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.


Qsar Study Of Chalcone Derivatives As Anti-Leishmania Agents, Maryam Iman, Asghar Davood, Nasim Banarouei Jan 2014

Qsar Study Of Chalcone Derivatives As Anti-Leishmania Agents, Maryam Iman, Asghar Davood, Nasim Banarouei

Turkish Journal of Chemistry

Quantitative structure activity relationship analyses were used to identify the ideal physicochemical characteristics of potential chalcone derivatives as anti-Leishmania agents. The HyperChem program was used to build chalcone structures and to perform conformational analyses through the semiempirical method followed by the PM3 force field. Dragon calculated a large number of molecular descriptors. Multilinear regression was used for quantitative structure activity relationship modeling. Based on our computational studies, 4 descriptors, SEigv, RDF125v, RDF055u, and O-058, can affect the activity of chalcone derivatives.


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 …


Graphene Oxide--Magnetite Nanocomposite As An Efficient And Magnetically Separable Adsorbent For Methylene Blue Removal From Aqueous Solution, Kadem Meral, Önder Meti̇n Jan 2014

Graphene Oxide--Magnetite Nanocomposite As An Efficient And Magnetically Separable Adsorbent For Methylene Blue Removal From Aqueous Solution, Kadem Meral, Önder Meti̇n

Turkish Journal of Chemistry

We report a facile method to produce a magnetically separable graphene oxide--magnetite nanocomposite (GO--Fe_3O_4) and its adsorption performance in methylene blue (MB) removal from aqueous solution. The GO--Fe_3O_4 nanocomposite was synthesized by a solution-phase self-assembly method including the incorporation of monodisperse Fe_3O_4 nanoparticles (NPs) and GO in a dimethylformamide/chloroform mixture under sonication. The successfully decorating GO sheet with monodisperse Fe_3O_4 NPs was proved by TEM study. ICP--OES data of the GO--Fe_3O_4 nanocomposite show that the GO--Fe_3O_4 nanocomposite consists of 21 wt% Fe_3O_4 NPs, which is sufficient for its magnetic separation from aqueous solution. The spectroscopic studies reveal that the GO--Fe_3O_4 …


Synthesis, Anticandidal Activity, And Cytotoxicity Of Some Thiazole Derivatives With Dithiocarbamate Side Chains, Leyla Yurttaş, Yusuf Özkay, Fati̇h Demi̇rci̇, Gamze Göger, Şafak Ulusoylar Yildirim, Usama Abu Mohsen, Ömer Öztürk, Zafer Asim Kaplancikli Jan 2014

Synthesis, Anticandidal Activity, And Cytotoxicity Of Some Thiazole Derivatives With Dithiocarbamate Side Chains, Leyla Yurttaş, Yusuf Özkay, Fati̇h Demi̇rci̇, Gamze Göger, Şafak Ulusoylar Yildirim, Usama Abu Mohsen, Ömer Öztürk, Zafer Asim Kaplancikli

Turkish Journal of Chemistry

Some thiazole derivatives bearing dithiocarbamic acid esters were synthesized in order to investigate their anticandidal activity and cytotoxicity. The structures of the obtained final compounds (6a--j) were confirmed by spectral data (IR, ^1H NMR, ^{13}C NMR, and MS) and elemental analysis. The anticandidal activity of the compounds was determined (6a--j) using the microbroth dilution method and their cytotoxicity was evaluated according to the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay against normal cells. Contrary to expectations, weak antifungal activity was observed with IC_{50} values ranging between 30 and 403 \mu g/mL.


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

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

Turkish Journal of Chemistry

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


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

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

Turkish Journal of Chemistry

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


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

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

Turkish Journal of Chemistry

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


History, Development, And A New Concept Of Phthalocyanines In Turkey, Özer Bekaroğlu Jan 2014

History, Development, And A New Concept Of Phthalocyanines In Turkey, Özer Bekaroğlu

Turkish Journal of Chemistry

This paper reviews the history of phthalocyanines in Turkey. Phthalocyanines are chemical compounds that were accidently discovered nearly a century ago. The relevant research and articles have grown dramatically in Turkey since our first paper on them containing four [15]crown[5] published in 1986. The ball-type phthalocyanines were produced and published as a new concept in phthalocyanine chemistry for the first time by our group in Turkey in 2006. Unfortunately, with the exception of our work on this subject, almost no papers have been published in Turkey or in other countries since then. We strongly urge scientists to consider working on …


Boron-Containing Tetrapyrroles, Şennur Özçeli̇k, Ahmet Gül Jan 2014

Boron-Containing Tetrapyrroles, Şennur Özçeli̇k, Ahmet Gül

Turkish Journal of Chemistry

The recent advances in the synthesis of carborane and boronic ester-substituted tetrapyrroles (porphyrins, porphyrazines, and phthalocyanines) are reviewed together with their possible utilization as agents for photodynamic therapy (PDT) and boron neutron capture therapy of cancer (BNCT) as well as dual PDT/BNCT sensitizers.


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 …


Novel Metal-Free And Metallophthalocyanines Containing Four 21-Membered Pentathiadiaza Macrocycles: Synthesis, Characterization, And Study Of Aggregation Properties, Hali̇l Zeki̇ Gök, Berna Farsak, Hülya Keleş, Mustafa Keleş Jan 2014

Novel Metal-Free And Metallophthalocyanines Containing Four 21-Membered Pentathiadiaza Macrocycles: Synthesis, Characterization, And Study Of Aggregation Properties, Hali̇l Zeki̇ Gök, Berna Farsak, Hülya Keleş, Mustafa Keleş

Turkish Journal of Chemistry

Metal-free phthalocyanine 3 and its metallophthalocyanine derivatives 4, 5, and 6 (M = Zn, Co, and Ni) substituted with four 21-membered pentathiadiaza macrocycles were synthesized and their structures identified by elemental analysis, IR, ^1H NMR, mass, and UV-Vis spectroscopy techniques. The aggregation properties of phthalocyanines 4, 5, and 6 were investigated in different solvents and at different concentrations of dimethylformamide.


Diphenylethoxy-Substituted Metal-Free And Metallophthalocyanines As Potential Photosensitizer For Photodynamic Therapy: Synthesis And Photophysical And Photochemical Properties, Yusuf Yilmaz, Ali̇ Erdoğmuş, Muhammet Kasim Şener Jan 2014

Diphenylethoxy-Substituted Metal-Free And Metallophthalocyanines As Potential Photosensitizer For Photodynamic Therapy: Synthesis And Photophysical And Photochemical Properties, Yusuf Yilmaz, Ali̇ Erdoğmuş, Muhammet Kasim Şener

Turkish Journal of Chemistry

The synthesis of a 4-(2,2-diphenylethoxy)phthalonitrile (1) and its organosoluble free base (2), zinc(II) (3), nickel(II) (4), and cobalt(II) (5) phthalocyanine derivatives is presented in this work. The novel complexes were characterized by elemental analyses and spectral data such as infrared, nuclear magnetic resonance, ultraviolet visible, and mass data. General tendencies were described for photophysics (fluorescence) and photochemistry (photodegradation and singlet oxygen quantum yields) of the free base and zinc(II) phthalocyanine derivatives in dimethylformamide. The quantum yield values of fluorescence (\Phi_F), singlet oxygen formation (\Phi_{\Delta}), and photodegradation (\Phi_d) for the zinc phthalocyanine were found to be 0.37, 0.48, and 9.12 \times …


Synthesis, Characterization, And Photophysical And Photochemical Properties Of 3-(4-Phenyloxy)Coumarin Containing Metallo- And Metal-Free Phthalocyanines, Nurullah Kartaloğlu, Ali̇ye Asli Esenpinar, Mustafa Bulut Jan 2014

Synthesis, Characterization, And Photophysical And Photochemical Properties Of 3-(4-Phenyloxy)Coumarin Containing Metallo- And Metal-Free Phthalocyanines, Nurullah Kartaloğlu, Ali̇ye Asli Esenpinar, Mustafa Bulut

Turkish Journal of Chemistry

The synthesis of novel zinc, cobalt, indium, and metal-free phthalocyanines carrying four 3-(4-phenyloxy)couma- rins in the periphery/nonperiphery were prepared by cyclotetramerization of 3-[4-(3,4-dicyanophenyloxy)phenyl]coumarin (2)/3-[4-(2,3- dicyanophenyloxy)phenyl]coumarin (3). The novel chromogenic compounds were characterized by elemental analysis, ^1H NMR, mass spectra, F-IR, and UV-vis spectral data. The effects of the coumarin units on the zinc, indium, and metal-free phthalocyanine complexes (2a/3a, 2c/3c, 2d/3d) were also investigated.


Synthesis And Spectral And Thermal Characterization Of New Metal-Free And Metallophthalocyanines: Investigation Of Their Photophysical, Photochemical, And Thin Film Properties, Eli̇f Çelenk Kaya, Mahmut Durmuş, Ekrem Yanmaz, Hali̇t Kanteki̇n Jan 2014

Synthesis And Spectral And Thermal Characterization Of New Metal-Free And Metallophthalocyanines: Investigation Of Their Photophysical, Photochemical, And Thin Film Properties, Eli̇f Çelenk Kaya, Mahmut Durmuş, Ekrem Yanmaz, Hali̇t Kanteki̇n

Turkish Journal of Chemistry

Novel tetrasubstituted metal-free (2), zinc (II) (3), cobalt (II) (4), and copper (II) (5) phthalocyanines bearing 2-phenylethanolate groups on the peripheral positions were synthesized by the cyclotetramerization reaction of the phthalonitrile derivative 1. The new compounds were characterized by a combination of IR, ^1H NMR, ^{13}C NMR, UV-Vis, elemental analysis, and MS spectra data. The thermal stabilities of the phthalocyanine compounds were determined by thermogravimetric analysis. For metal-free (2) and zinc (3) phthalocyanines, photochemical (photodegradation and singlet oxygen quantum yields) and photophysical (fluorescence quantum yields and fluorescence lifetimes) properties were analyzed in dimethylsulfoxide (DMSO). The cobalt (4) and copper (5) …