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2012

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Articles 11071 - 11100 of 12196

Full-Text Articles in Physical Sciences and Mathematics

Optimization Of A New Cloud Point Extraction Procedure For The Selective Determination Of Trace Amounts Of Total Iron In Some Environmental Samples, Celal Duran, Duygu Özdeş, Eli̇f Çelenk Kaya, Hali̇t Kanteki̇n, Volkan Numan Bulut, Mehmet Tüfekçi̇ Jan 2012

Optimization Of A New Cloud Point Extraction Procedure For The Selective Determination Of Trace Amounts Of Total Iron In Some Environmental Samples, Celal Duran, Duygu Özdeş, Eli̇f Çelenk Kaya, Hali̇t Kanteki̇n, Volkan Numan Bulut, Mehmet Tüfekçi̇

Turkish Journal of Chemistry

A new, simple, and rapid cloud point extraction (CPE) procedure system, combined with flame atomic absorption spectrometry (FAAS), was developed for selective separation, preconcentration, and determination of trace amounts of total iron in some environmental samples. The complexing agent, N,N'-(2,2'-(ethane-1,2-diylbis(oxy)) bis(ethane-2,1-diyl))bis(2-chloroacetamide) (EDBOCA), is selective at pH 5.0 for only Fe(II) and Fe(III) ions in the presence of Cu(II), Pb(II), Cd(II), Mn(II), Co(II), Cr(III), Cr(VI), Ni(II), Zn(II), Al(III), Mo(VI), Pd(II), Pt(IV), Au(III), and V(V) ions. The procedure is based on the complexation of Fe(III) ions with EDBOCA reagent in the presence of Triton X-114 (TX-114) as a non-ionic surfactant. The optimum …

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Silica Nanoparticles As A High Efficient Catalyst For The One-Pot Synthesis Of 3-Oxo-3-Phenylpropanamid Derivatives From Isocyanides, Phenylacetaldehyde And Secondary Amines, Ali Ramazani, Kourosh Dastanra, Fatemeh Zeinali Nasrabadi, Zahra Karimi, Morteza Rouhani, Mehdi Hosseini Jan 2012

Silica Nanoparticles As A High Efficient Catalyst For The One-Pot Synthesis Of 3-Oxo-3-Phenylpropanamid Derivatives From Isocyanides, Phenylacetaldehyde And Secondary Amines, Ali Ramazani, Kourosh Dastanra, Fatemeh Zeinali Nasrabadi, Zahra Karimi, Morteza Rouhani, Mehdi Hosseini

Turkish Journal of Chemistry

Reaction of an isocyanide with an iminium ion intermediate, formed by reaction between 2-oxo-2-phenylacetaldehyde and a secondary amine in the presence of silica nanoparticles, proceeds smoothly at room temperature to afford ketoamide derivatives in high yields.

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Transmission Ft-Ir Spectroscopic Analysis Of Human Kidney Stones In The Hyderabad Region Of Pakistan, Muhammad Hussan Khaskheli, Syed Tufail Hussain Sherazi, Huma Mazhar Ujan, Sarfaraz Ahmed Mahesar Jan 2012

Transmission Ft-Ir Spectroscopic Analysis Of Human Kidney Stones In The Hyderabad Region Of Pakistan, Muhammad Hussan Khaskheli, Syed Tufail Hussain Sherazi, Huma Mazhar Ujan, Sarfaraz Ahmed Mahesar

Turkish Journal of Chemistry

The purpose of the present study was to investigate the composition of kidney stones removed from human patients. Seventeen samples were collected after surgery (5 females and 12 males; age range 2 to 60 years). The samples were analyzed for composition by transmission Fourier transform infrared (FT-IR) spectroscopy. The 17 analyzed samples of kidney stones comprised 29.4% calcium oxalate, 29.4% uric acid, 29.4% calcium oxalate (CaOx)-uric acid, 5.9% phosphate, and 5.9% calcium oxalate-phosphate stones. The results of the study indicated that transmission FT-IR spectroscopy could be used as an environmentally friendly technique for rapid screening of kidney stones.

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The Reaction Of Dialkyl Acetylenedicarboxylates With 2-Oxo-2-Phenylacetaldehyde In The Presence Of Primary Amines: Synthesis Of Alkyl 2-Benzoyl-4-Alkylamino-5-Oxo-2,5-Dihydro-3-Furan Carboxylate Derivatives, Javad Safaei Ghomi, Fariba Salimi, Ali Ramazani, Fatemeh Zeinali Nasrabadi, Yavar Ahmadi Jan 2012

The Reaction Of Dialkyl Acetylenedicarboxylates With 2-Oxo-2-Phenylacetaldehyde In The Presence Of Primary Amines: Synthesis Of Alkyl 2-Benzoyl-4-Alkylamino-5-Oxo-2,5-Dihydro-3-Furan Carboxylate Derivatives, Javad Safaei Ghomi, Fariba Salimi, Ali Ramazani, Fatemeh Zeinali Nasrabadi, Yavar Ahmadi

Turkish Journal of Chemistry

A 3-component domino reaction approach between a primary amine, a dialkyl acetylenedicarboxylate, and 2-oxo-2- phenylacetaldehyde that affords novel alkyl 2-benzoyl-4-alkylamino- 5-oxo-2,5-dihydro-3-furan carboxylate derivatives is reported. The reaction sequence consists of an initial Michael addition of primary amines to dialkyl acetylenedicarboxylates, followed by an aldol-like reaction with 2-oxo-2-phenylacetaldehyde, and then \gamma -lactonization to afford the products. This cascade reaction sequence represents a rapid and unprecedented route to the described biologically interesting molecules.

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Symmetric, Twinned, And Double-Decker Phthalocyanines Substituted By Trialkylated Pentaerythritol, Muzaffer Köç, Ayşe Gül Gürek, Fabienne Dumoulin, Vefa Ahsen Jan 2012

Symmetric, Twinned, And Double-Decker Phthalocyanines Substituted By Trialkylated Pentaerythritol, Muzaffer Köç, Ayşe Gül Gürek, Fabienne Dumoulin, Vefa Ahsen

Turkish Journal of Chemistry

Trialkylated pentaerythritol was chosen as a bulky substituent for a set of 3 free-base phthalocyanines: a symmetric, a twinned, and a double-decker derivative. The bulkiness of this substituent lowered the aggregation of the phthalocyanines. The electronic absorptions were comparatively investigated: the twinned phthalocyanine exhibited a significant near-infrared shifted absorption. The neutral radical Eu(III) complex was oxidized by bromine. These 3 phthalocyanines are promising for use as molecular materials.

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A New Absorption Based Co_2 Sensor Based On Schiff Base Doped Ethyl Cellulose, Sevi̇nç Zehra Topal, Kadri̇ye Erteki̇n, Beri̇n Yeni̇gül, Ayşe Erçağ Jan 2012

A New Absorption Based Co_2 Sensor Based On Schiff Base Doped Ethyl Cellulose, Sevi̇nç Zehra Topal, Kadri̇ye Erteki̇n, Beri̇n Yeni̇gül, Ayşe Erçağ

Turkish Journal of Chemistry

This paper reports absorption-based CO_2 sensing of the pH-active Schiff base 2-[(2-hydroxymethylphenylimino) methyl]-5-bromo-phenol (SB) in an ethyl cellulose (EC) matrix with and without Teflon coating. The CO_2 sensitivity of the SB dye in the EC matrix was evaluated in the presence of nonadecafluorodecanoic acid and tetrabutyl ammonium hydroxide. When exposed to CO_2, the sensing films exhibited 76% of overall relative signal change and responded to CO_2 over a wide range: 1%-100 % (v/v). However, the slope of the spectral response between 1% and 5% (v/v) is more significant. The response time (\tau_{90}) was 15 s, and limit of detection (LOD) …

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Design, Synthesis, And Biological Evaluation Of Indole-Based 1,4-Disubstituted Piperazines As Cytotoxic Agents, Meri̇ç Köksal Akkoç, Mi̇ne Yarim Yüksel, İrem Durmaz, Rengül Çeti̇n Atalay Jan 2012

Design, Synthesis, And Biological Evaluation Of Indole-Based 1,4-Disubstituted Piperazines As Cytotoxic Agents, Meri̇ç Köksal Akkoç, Mi̇ne Yarim Yüksel, İrem Durmaz, Rengül Çeti̇n Atalay

Turkish Journal of Chemistry

A series of 3-[(4-substitutedpiperazin-1-yl)methyl]-1H-indole derivatives were synthesized, and their structures were confirmed by spectral analysis. All the compounds were tested for their cytotoxic activity in vitro against 3 human tumor cell lines: human liver (HUH7), breast (MCF7), and colon (HCT116). Among the designed derivatives, most of the compounds showed significant cytotoxicity against liver and colon cancer cell lines with lower IC_{50} concentrations than the standard drug 5-fluorouracil. Compound 3s, with 3,4-dichlorophenyl substituent on the piperazine ring, was the most active in suppressing the growth of all screened cancer cells.

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Simultaneous Determination Of Dopamine, Uric Acid, And Tryptophan Using An Mwcnt Modified Carbon Paste Electrode By Square Wave Voltammetry, Hadi Beitollahi, Alireza Mohadesi, Saeedeh Khalilizadeh Mahani, Hassan Karimi Maleh, Ali Akbari Jan 2012

Simultaneous Determination Of Dopamine, Uric Acid, And Tryptophan Using An Mwcnt Modified Carbon Paste Electrode By Square Wave Voltammetry, Hadi Beitollahi, Alireza Mohadesi, Saeedeh Khalilizadeh Mahani, Hassan Karimi Maleh, Ali Akbari

Turkish Journal of Chemistry

A highly sensitive method was investigated for the simultaneous determination of dopamine (DA), uric acid (UA), and tryptophan (TRP) using a multiwall carbon nanotubes/5-amino-3',4'-dimethoxy-biphenyl-2-ol modified carbon paste electrode (5ADMBCNPE). The 5ADMBCNPE displayed excellent electrochemical catalytic activities towards the oxidation of DA, UA, and TRP. The electrochemical profile of the proposed modified electrode was analyzed by cyclic voltammetry (CV), which showed a shift in the oxidation peak potential of DA at 160 mV to a less positive value compared with an unmodified carbon paste electrode. Square wave voltammetry (SWV) in 0.1 M phosphate buffer solution (PBS) at pH 7.0 was performed …

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Three-Component Passerini-Smiles Coupling Reaction Of Aldehydes And Isocyanides With Tropolone Catalyzed By Silica Nanoparticles, Abdolhossain Massoudi, Issa Amini, Ali Ramazani, Fatemeh Zeinali Nasrabadi Jan 2012

Three-Component Passerini-Smiles Coupling Reaction Of Aldehydes And Isocyanides With Tropolone Catalyzed By Silica Nanoparticles, Abdolhossain Massoudi, Issa Amini, Ali Ramazani, Fatemeh Zeinali Nasrabadi

Turkish Journal of Chemistry

The use of Smiles rearrangement in Passerini-type couplings with tropolone allows very straightforward multicomponent formation of \alpha-aryloxy amide derivatives. The 3-component addition of isocyanide to tropolone (2-hydroxy-2,4,6-cycloheptatrien-1-one) and aldehyde in the presence of silica nanoparticles (silica NP, ca. 70 nm) proceeds easily in methanol to form the title compounds in a new Passerini-Smiles-type reaction.

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Microwave-Assisted Synthesis, Spectroscopy, And Crystal Structures Of [(H_2-(4,4'-Bipy)]^{2+} [Cr_2o_7]^{2-} And One-Dimensional Polymeric {[Mn(4,4'-Bipy)(Cr_2o_7)(H_2o)_2]\}_N Compounds, Hirihattaya Phetmung, Munee Wateh, Chaveng Pakawatchai Jan 2012

Microwave-Assisted Synthesis, Spectroscopy, And Crystal Structures Of [(H_2-(4,4'-Bipy)]^{2+} [Cr_2o_7]^{2-} And One-Dimensional Polymeric {[Mn(4,4'-Bipy)(Cr_2o_7)(H_2o)_2]\}_N Compounds, Hirihattaya Phetmung, Munee Wateh, Chaveng Pakawatchai

Turkish Journal of Chemistry

A compound (1), [H_2-(4,4'-bipy)]^{2+}[(Cr_2O_7)]^{2-} and a metal organic-inorganic coordination framework (2), [Mn(4,4'-bipy)(Cr_2O_77)(H_2O)_2] (4,4'-bipy=4,4' -bipyridine) were successfully synthesized by microwave method. Their characterization was performed by single crystal X-ray crystallography and FT-IR spectroscopy. The crystal structure of 1 revealed a diprotonated 4,4'-bipyridium dichromate compound while compound 2 is an onedimensional (1D) polymer in which (Cr_2O_7)^{2-} acts as a bridging ligand supporting the formation of infinite {[Mn(4,4'-bipy)(Cr_2O_7)(H_2O)_2]}_n polymeric chains. The geometry of the 4,4'-bipy ring in 1 is typical coplanar, but twists in 2. In the free molecule 1, dichromate ligand adopts an eclipsed conformation, but adopts a staggered conformation in complex. …

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Reduction, Mannich Reaction And Antimicrobial Activity Evaluation Of Some New 1,2,4-Triazol-3-One Derivatives, Seda Fandakli, Serap Başoğlu, Hakan Bektaş, Meltem Yolal, Ahmet Demi̇rbaş, Şengül Alpay Karaoğlu Jan 2012

Reduction, Mannich Reaction And Antimicrobial Activity Evaluation Of Some New 1,2,4-Triazol-3-One Derivatives, Seda Fandakli, Serap Başoğlu, Hakan Bektaş, Meltem Yolal, Ahmet Demi̇rbaş, Şengül Alpay Karaoğlu

Turkish Journal of Chemistry

Ethyl[4-arylmethyleneamino-3-(4-metylphenyl)-5-oxo-4,5-dihydro- 1H-1,2,4-triazole-1-yl]acetates (3a-e and 10a-d) were obtained starting from 4-amino-2,4-dihydro-3H-1,2,4-triazol-3-ones (1 and 9) in 2 steps. The treatment of 3a-e with NaBH_4 resulted in the formation of 3 kinds of product incorporating carboxcilic acid (4a-c) or alcohol (5a-e) functionality. [4-{[(4-Methoxyphenyl)methylene]amino}- and 4-{[pyridin-4-ylmethylene]amino}-3-(4-methylphenyl)-5-oxo-4,5-dihydro-1H- 1,2,4-triazole-1-yl] acetic acids (6a, 6e) were obtained by the hydrolysis of the corresponding esters (5a-5e). The treatment of 6a with NaBH_4 caused the reduction of only the imine bond; the carboxyl group remained unchanged. Then this carboxylic acid was converted to the corresponding hydrazide (8) in 2 steps by reaction with ethanol and hydrazine hydrate, respectively. The synthesis …

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Synthesis And Cytotoxic Evaluation Of Uracil C-Mannich Bases, Hüseyi̇n İstanbullu, Istvan Zupko, Vi̇ldan Alptüzün, Erçi̇n Erci̇yas Jan 2012

Synthesis And Cytotoxic Evaluation Of Uracil C-Mannich Bases, Hüseyi̇n İstanbullu, Istvan Zupko, Vi̇ldan Alptüzün, Erçi̇n Erci̇yas

Turkish Journal of Chemistry

This study covers the design, synthesis, characterization, and cytotoxic activity of a series of uracil C-Mannich bases. Among them, one hybrid compound (1), a molecular combination of the potential antimetabolite substituted uracil and nitrogen mustard, having potential alkylating capability, was prepared as a Mannich base. The other compound was synthesized with the replacement of chlorines in the ethyl chains with hydroxyl groups for testing for anticancer activity. Some of Mannich bases having several amino groups with different pKa values were also synthesized and investigated in terms of cytotoxic activity. Their chemical structures were confirmed by means of their UV, IR, …

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Determination Of Lidocaine Based On Electrocatalysis Of A Chemically Modified Electrode, Gamze Tan, Gülçi̇n Bolat, Mehmet Ali̇ Onur, Serdar Abaci Jan 2012

Determination Of Lidocaine Based On Electrocatalysis Of A Chemically Modified Electrode, Gamze Tan, Gülçi̇n Bolat, Mehmet Ali̇ Onur, Serdar Abaci

Turkish Journal of Chemistry

The potential application of biochemically modified electrodes was investigated for construction of a drug biosensor. The electrocatalytic response of lidocaine was examined through modified electrodes using the electron transfer ability of hemoglobin (Hb) immobilized on gold film modified with a self-assembled monolayer (SAM) of 3-mercaptopropionic acid (MPA). According to the results of voltammetric studies, Au/MPA/Hb electrodes exhibited high sensitivity and good electrocatalytic activity for the reduction of lidocaine, motivating us to construct drug biosensors. With this study, a new electroanalytical procedure is proposed for the determination of lidocaine level in medical applications or therapeutic formulations containing lidocaine as the active …

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Synthesis And Structural Characterization Of Novel Square Pyramidal Oxovanadium(Iv) Complexes With Ligands Having N And O Donor Atoms, Ashok Kumar Yadava, Hardeo Singh Yadav, Uma Shanker Yadav, Devendra Pratap Rao Jan 2012

Synthesis And Structural Characterization Of Novel Square Pyramidal Oxovanadium(Iv) Complexes With Ligands Having N And O Donor Atoms, Ashok Kumar Yadava, Hardeo Singh Yadav, Uma Shanker Yadav, Devendra Pratap Rao

Turkish Journal of Chemistry

Oxovanadium(IV) complexes having the general formula [VO(L)] were designed and synthesized using vanadyl ion as kinetic template with ligands derived by condensation of \beta-diketones such as acetylacetone, benzoylacetone, thenoyltrifluoroacetone, and dibenzoylmethane with 2-amino-3-hydroxypyridine or 2-aminobenzoic acid or 2-aminonicotinic acid. Tentative structures of the complexes were proposed on the basis of elemental analysis, molar conductance, magnetic moments, and spectral (infrared, electronic and electron spin resonance) data. All the oxovanadium(IV) complexes are 5-coordinated wherein derived ligands act as tetradentate chelating agents.

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In Situ Formed 1-Hexyl-3-Methylimidazolium Hexafluorophosphate For Dispersive Liquid-Liquid Microextraction Of Pd(Ii) Prior To Electrothermal Aas And Spectrophotometry, Habibollh Eskandari Jan 2012

In Situ Formed 1-Hexyl-3-Methylimidazolium Hexafluorophosphate For Dispersive Liquid-Liquid Microextraction Of Pd(Ii) Prior To Electrothermal Aas And Spectrophotometry, Habibollh Eskandari

Turkish Journal of Chemistry

1-Hexyl-3-methylimidazolium hexafluorophosphate was prepared in situ and used as extractant in dispersive liquid-liquid microextraction. Ultra-trace amounts of Pd(II) could be accurately determined by electrothermal atomic absorption spectrometry (ETAAS) and spectrophotometry after extraction by the formed micro-droplets of the ionic liquid phase. 1-(2-Pyridylazo)-2-naphthol was used to produce a hydrophobic palladium complex prior to extraction. The effects of concentrations of reagents, reaction and extraction times, and the other parameters were investigated and optimized. Beer's law was obeyed in the ranges of 0.015-0.900 and 1.50-63.0 ng mL^{-1} Pd(II) by ETAAS and spectrophotometry, respectively. Under the optimized conditions, the limit of detection (LOD) by …

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Determination Of Ascorbic Acid By A Modified Multiwall Carbon Nanotube Paste Electrode Using Cetrimonium Iodide/Iodine, Meissam Noroozifar, Mozhgan Khorasani Motlagh, Hamed Tavakoli Jan 2012

Determination Of Ascorbic Acid By A Modified Multiwall Carbon Nanotube Paste Electrode Using Cetrimonium Iodide/Iodine, Meissam Noroozifar, Mozhgan Khorasani Motlagh, Hamed Tavakoli

Turkish Journal of Chemistry

A new modified graphite-multiwall carbon nanotube paste electrode for the determination of ascorbic acid (AA) based on cetrimonium iodide-iodine is described. The electrochemical response characteristics of the modified electrode toward AA were investigated by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) in phosphate buffer solution (pH 2.0). When compared to activated carbon, graphite, and multiwall carbon nanotube paste electrode containing new modifier, the proposed modified paste electrode not only shifted the oxidation potential of AA towards less positive potential but also enhanced its oxidation peak current. Further, the oxidation of AA was highly stable at the modified paste electrode. …

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Synthesis And Antimicrobial Activity Of Some Novel 4-Hydroxyquinolin-2(1h)-Ones And Pyrano[3,2-C] Quinolinones From 3-(1-Ethy1-4-Hydroxy-2-Oxo-1,2-Dihydroquinolin-3-Yl)-3-Oxopropanoic Acid, Hany Mohamed Hassanin, Magdy Ahmed Ibrahim, Youssef Abdel-Salam Alnamer Jan 2012

Synthesis And Antimicrobial Activity Of Some Novel 4-Hydroxyquinolin-2(1h)-Ones And Pyrano[3,2-C] Quinolinones From 3-(1-Ethy1-4-Hydroxy-2-Oxo-1,2-Dihydroquinolin-3-Yl)-3-Oxopropanoic Acid, Hany Mohamed Hassanin, Magdy Ahmed Ibrahim, Youssef Abdel-Salam Alnamer

Turkish Journal of Chemistry

Chlorination, bromination, and condensation reactions of 3-(1-ethy1-4-hydroxy-2-oxo-1,2-dihydroquinolin-3-yl)-3-oxopropanoic acid (3) were studied. Some novel 4-hydroxyquinolin-2(1H)-ones and pyrano[3,2-c]quinolin-2(1H)-ones were also prepared. The structures of the novel compounds were established by elemental analyses and spectral data. All the products were also screened in vitro for their antimicrobial activity.

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Preparation Of Porphyrinated Polyacrylonitrile Fiber Mat Supported Tio_2 Photocatalyst And Its Photocatalytic Activities, Linjun Shao, Ji Chen, Luyao He, Guiying Xing, Weixi Lv, Zaina Chen, Chenze Qi Jan 2012

Preparation Of Porphyrinated Polyacrylonitrile Fiber Mat Supported Tio_2 Photocatalyst And Its Photocatalytic Activities, Linjun Shao, Ji Chen, Luyao He, Guiying Xing, Weixi Lv, Zaina Chen, Chenze Qi

Turkish Journal of Chemistry

Fe(III)meso-tetraphenylporphyrinated polyacrylonitrile fiber mat supported TiO_2 photocatalyst (PANC/ TiO_2 mat) was prepared via copolymerization and electrospinning. SEM images showed that well-defined fibers with diameters around 1.47 \pm 0.26 \mu m were fabricated from Fe(III)meso-tetraphenylporphyrin (FeTPP)-acrylonitrile copolymer (PANC) and TiO_2 mixture. The XRD characterizations demonstrated that the electrospinning process had no effect on the anatase structure of TiO_2. The photocatalytic activity of the PANC/TiO_2 mat was examined for the photodegradation of methyl red in aqueous solution under the irradiation of visible light. The results showed that this PANC/TiO_2 fiber mat was very efficient for the photodegradation of methyl red, with a …

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Preparation, Morphology, And Thermal And Optical Properties Of Thin Films Of Ferric Chloride/Polyethylene Oxide Composites, Sabiha Sultana, Muhammad Saleem Khan, Muhammad Humayun Jan 2012

Preparation, Morphology, And Thermal And Optical Properties Of Thin Films Of Ferric Chloride/Polyethylene Oxide Composites, Sabiha Sultana, Muhammad Saleem Khan, Muhammad Humayun

Turkish Journal of Chemistry

Pure poly (ethylene oxide) (PEO) films and PEO-FeCl_3 films of various concentration were prepared and studied for thermal and optical properties. Various analytical techniques like XRD, EDX, SEM, TGA, and UV were used to examine the structural properties of PEO and PEO-FeCl_3 systems. X-ray scans (XRD) revealed the existence of some crystalline part in the PEO matrix. The concentration of FeCl_3 has a great effect on the crystallinity of PEO. Thermogravimetric analysis (TGA) data established that accumulation of FeCl_3 to PEO films enhanced the thermal stability of PEO. The optical properties of these systems were also studied in the UV-Visible …

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Synthesis Of Antipyrine/Pyridazinone Hybrids And Investigation Of Their In Vivo Analgesic And Anti-Inflammatory Activities, Sultan Baytaş, Nazan İnceler, Khatereh Fattahpour Mavaneh, Meci̇t Orhan Uludağ, Nuretti̇n Abacioğlu, Mehtap Gökçe Jan 2012

Synthesis Of Antipyrine/Pyridazinone Hybrids And Investigation Of Their In Vivo Analgesic And Anti-Inflammatory Activities, Sultan Baytaş, Nazan İnceler, Khatereh Fattahpour Mavaneh, Meci̇t Orhan Uludağ, Nuretti̇n Abacioğlu, Mehtap Gökçe

Turkish Journal of Chemistry

Eleven antipyrine/pyridazinone hybrids were synthesized and evaluated for their in vivo analgesic and anti-inflammatory activities by p-benzoquinone-induced writhing test and carrageenan-induced paw edema model, respectively. The test results indicated that compounds 6a, 6c, and 6d were equally or more potent analgesic and anti-inflammatory agents than aspirin and indomethacin, respectively. Side effects of the compounds were examined on gastric mucosa. Most of the compounds were found to be non-ulcerogenic under test conditions.

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Substituent Effects On The Regioselectivity Of Maleamic Acid Formation And Hydrogen Chloride Addition To N-Aryl Maleimides, Yeli̇z Faturaci, Necdet Coşkun Jan 2012

Substituent Effects On The Regioselectivity Of Maleamic Acid Formation And Hydrogen Chloride Addition To N-Aryl Maleimides, Yeli̇z Faturaci, Necdet Coşkun

Turkish Journal of Chemistry

Itaconic anhydride reacts with aryl amines to give a substituent controlled equilibrium mixture of regioisomeric (Z)-2-methyl- and (Z)-3-methyl-4-oxo-4-(arylamino)but-2-enoic acids. Electron-donating groups favor nucleophilic attack on C-5 carbonyl, while the presence of electron-withdrawing groups enhances the bias for attack on C-2 carbonyl. The treatment of (Z)-2-methyl- and (Z)-3-methyl-4-oxo-4-(arylamino)but-2-enoic acids with SOCl_2-Et_3N in THF provided the corresponding maleimides in high yields while under the same conditions the maleic anhydride aryl amine addition products gave predominately the corresponding 3-chloro-1-arylpyrrolidine-2,5-diones and maleimides in substituent dependent ratio.

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Synthesis And Structural X-Ray Analysis Of 1,1'-(Naphthalene-1,8-Diyl)-3,3'-Dibenzoyl-Bisthiourea And Its Use As Anion-Binding Receptor, Fatma Aydin, Nazan Tunoğlu, Doğan Aykaç, Nahi̇de Burcu Arslan, Canan Kazak Jan 2012

Synthesis And Structural X-Ray Analysis Of 1,1'-(Naphthalene-1,8-Diyl)-3,3'-Dibenzoyl-Bisthiourea And Its Use As Anion-Binding Receptor, Fatma Aydin, Nazan Tunoğlu, Doğan Aykaç, Nahi̇de Burcu Arslan, Canan Kazak

Turkish Journal of Chemistry

A novel artificial receptor, 1,1'-(naphthalene-1,8-diyl)-3,3'- dibenzoyl-bisthiourea, based on a 1,8-naphthalene skeleton bearing bisthiourea groups was prepared and characterized by IR and ^1H-NMR, ^{13}C-NMR, and MS spectroscopic techniques. The compound proved to be an efficient and selective naked-eye detector for the fluoride, cyanide, and hydroxide ions in DMSO. The crystal structure of the title compound was examined by using X-ray crystallographic techniques and found to be crystallized in the monoclinic space group P -1 with the unit cell parameters: a = 8.1556(8) Å, b = 12.0127(11) Å, c = 13.2081(11) Å, \alpha = 109.510(7)°, \beta = 95.390(7)°, \gamma = 103.660(7)°, Z …

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Preparation Of 2-(N,N-Dialkylamino)-2,4,6- Cycloheptatrien-1-One Derivatives From An Isocyanide, A Primary Amine, Propionaldehyde, And Tropolone Via Ugi-Smiles Coupling Reaction In The Presence Of Silica Nanoparticles, Abdolhossain Massoudi, Issa Amini, Ali Ramazani, Fatemeh Zeinali Nasrabadi Jan 2012

Preparation Of 2-(N,N-Dialkylamino)-2,4,6- Cycloheptatrien-1-One Derivatives From An Isocyanide, A Primary Amine, Propionaldehyde, And Tropolone Via Ugi-Smiles Coupling Reaction In The Presence Of Silica Nanoparticles, Abdolhossain Massoudi, Issa Amini, Ali Ramazani, Fatemeh Zeinali Nasrabadi

Turkish Journal of Chemistry

The use of Smiles rearrangement in Ugi-type couplings with tropolone allows very straightforward multicomponent formation of 2-(N,N-dialkylamino)-2,4,6-cycloheptatrien-1-one derivatives. The 4-component reaction of isocyanides, tropolone (2-hydroxy-2,4,6- cycloheptatrien-1-one), primary amines, and propionaldehyde in the presence of silica nanoparticles (silica NPs, ca. 42 nm) proceeds easily in methanol to form the title compounds in a new Ugi--Smiles-type reaction.

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Bifunctionalized Linked Bis-Spiro[Furo[2,3-D]Pyrimidine-6,5'- Pyrimidine]2,2',4,4',6'(3h,3'H,5h)-Pentaones Derived From One-Pot Reaction Of (Thio)Barbituric Acids With Aromatic Dialdehydes And Brcn In The Presence Of Et_3n, Nader Noroozi Pesyan, Mohammad Jalilzadeh Jan 2012

Bifunctionalized Linked Bis-Spiro[Furo[2,3-D]Pyrimidine-6,5'- Pyrimidine]2,2',4,4',6'(3h,3'H,5h)-Pentaones Derived From One-Pot Reaction Of (Thio)Barbituric Acids With Aromatic Dialdehydes And Brcn In The Presence Of Et_3n, Nader Noroozi Pesyan, Mohammad Jalilzadeh

Turkish Journal of Chemistry

Reaction of pyrimidine-(1H,3H,5H)-2,4,6-trione (barbituric acid), 1,3-dimethyl pyrimidine-(1H,3H,5H)-2,4,6-trione (1,3-dimethyl barbituric acid), and 1,3-diethyl-2-thioxodihydropyrimidine-4,6(1H,5H)- dione (1,3-diethyl thiobarbituric acid) with cyanogen bromide and aromatic dialdehydes in the presence of triethylamine leads to the selective and efficient formation of a novel class of bifunctionalized stable heterocyclic bis-spiro[furo[2,3-d]pyrimidine-6,5'-pyrimidine] 2,2',4,4',6'(3H,3'H,5H)pentaones and their sulfur analogues, which are dimeric forms of barbiturate linked by a phenyl ring. A proposed mechanism was suggested for the formation of the products. The reaction of phthalaldehyde with BrCN and (thio)barbituric acids resulted in only monofunctionalized spiro[furo[2,3-d]pyrimidine-6,5'- pyrimidine]2,2',4,4',6'(3H,3'H,5H)pentaones, while isophthalaldehyde and terphthalaldehyde resulted in the bifunctionalized form.

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Synthetic Access To Benzazolyl (Pyrazoles, Thiazoles, Or Triazoles), Bakr Fathy Abdelwahab, Hanan Ahmed Mohamed Jan 2012

Synthetic Access To Benzazolyl (Pyrazoles, Thiazoles, Or Triazoles), Bakr Fathy Abdelwahab, Hanan Ahmed Mohamed

Turkish Journal of Chemistry

This review surveys data published in recent years on the synthesis of benzazoles linked directly with pyrazoles, thiazoles, or triazoles. Some of the commercial applications are mentioned.

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Synthesis, Structural Characterization, And Benzyl Alcohol Oxidation Activity Of Mononuclear Manganese(Ii) Complex With 2,2'-Bipyridine: [Mn(Bipy)_2(Clo_4)_2], İbrahi̇m Kani̇, Mehmet Kurtça Jan 2012

Synthesis, Structural Characterization, And Benzyl Alcohol Oxidation Activity Of Mononuclear Manganese(Ii) Complex With 2,2'-Bipyridine: [Mn(Bipy)_2(Clo_4)_2], İbrahi̇m Kani̇, Mehmet Kurtça

Turkish Journal of Chemistry

A manganese(II) complex of 2,2'-bipyridine (bipy) was synthesized and characterized by X-ray diffraction, IR, and UV-vis spectroscopy. The activity of the complex was tested for oxidation of benzyl alcohols using t-BuOOH as an oxidant in organic solvents and in an organic/water biphasic system (hexane/H_2O, toluene/H_2O). The effect of solvent, temperature, oxidant, and some additives (KBr, N(C_4H_9)Br, and N-bromosuccinimide) on the oxidation of benzyl alcohol is reported. The results show that benzyl alcohol was selectively converted to benzaldehyde in 71.9% yield within 4 h in acetonitrile. Control experiments performed without catalyst and the corresponding metal salt as catalyst produced no benzaldehyde …

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Properties Of The Mixed Adsorption Layer: Neutral Detergent-Tetramethylthiourea At Interface Electrode/Solution, Jolanta Nieszporek, Dorota Sienko, Dorota Gugala-Fekner, Malgorzata Klin Jan 2012

Properties Of The Mixed Adsorption Layer: Neutral Detergent-Tetramethylthiourea At Interface Electrode/Solution, Jolanta Nieszporek, Dorota Sienko, Dorota Gugala-Fekner, Malgorzata Klin

Turkish Journal of Chemistry

The mixed adsorption layers of tetramethylthiourea and a neutral detergent formed at the electrode surface in 1 M NaClO_4 are described in this paper. The systems were characterized by the measurement of differential capacity, zero charge potential, and surface tension at the same potential. The data were analyzed to obtain the surface pressure and relative surface excess of tetramethylthiourea as a function of electrode charge and bulk concentration of the studied compounds. The values of the lateral interaction parameters, obtained in the presence and in the absence of decanoyl-N-methylglucamide (C_{17}H_{35}NO_6), change differently depending on the isotherm used, but \Delta G° …

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Efficient One-Pot Alkylation Of Imines Using Nanosilver Iodide In Aqueous Media, Javad Safaei Ghomi, Ahmad Kakavand-Qalenoei, Mohammad Ali Ghasemzadeh, Masoud Salavati-Niasari Jan 2012

Efficient One-Pot Alkylation Of Imines Using Nanosilver Iodide In Aqueous Media, Javad Safaei Ghomi, Ahmad Kakavand-Qalenoei, Mohammad Ali Ghasemzadeh, Masoud Salavati-Niasari

Turkish Journal of Chemistry

An efficient ecofriendly method for the alkylation reaction of various imines is described by a simple one-pot reaction of aldehydes, amines and alkyl iodides in the presence of AgI nanoparticles in aqueous media. Silver iodide nanoparticles mediated an enhanced rate and facility of reaction and showed high influence in the green synthesis of some amine derivatives. Moreover, this nanoparticle increased the yields of products and decreased the reaction times in all cases. The heterogeneous mediator was fully characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and FT-IR experimental techniques.

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Synthesis Of 3-Pyrroline-2-Ones From Amino Acids And An Aryl Amine, Nezi̇re Saygili, Cemi̇l Aydoğan Jan 2012

Synthesis Of 3-Pyrroline-2-Ones From Amino Acids And An Aryl Amine, Nezi̇re Saygili, Cemi̇l Aydoğan

Turkish Journal of Chemistry

The conversion of the amino group of amino dicarboxylicacid esters and an aryl amine into N-substituted pyrrolinone derivatives with dimethoxydihydrofurane is described. The conversion also occurs with serine methylester but it decomposes very quickly.

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A Novel Soluble Phthalocyanine Capable Of Binding Four Boronic Esters, Şennur Özçeli̇k, Gülnur Keser Karaoğlan, Gülşah Gümrükçü, Ahmet Gül Jan 2012

A Novel Soluble Phthalocyanine Capable Of Binding Four Boronic Esters, Şennur Özçeli̇k, Gülnur Keser Karaoğlan, Gülşah Gümrükçü, Ahmet Gül

Turkish Journal of Chemistry

A novel Zn phthalocyanine bearing 4 salicylideniminophenyloxy substituents on peripheral positions was synthesized from the reaction of 4-aminophenoxy substituted phthalocyanine and salicylaldehyde. The condensation reaction of salicylidene Schiff base groups and benzeneboronic acid produced a new phthalocyanine carrying benzeneboronic acid ester derivatives as substituents. Ethoxy groups were bound to boronic acid as a second ligand. The presence of B-N bond interactions enhanced the stability of this boronated phthalocyanine derivative, which exhibited sufficient air stability during the purification and characterization processes. The novel compounds were characterized by using elemental analysis, IR, ^1H-NMR, ^{11}B-NMR, ^{13}C-NMR, UV-Vis and MALDI-TOF MS spectral data.

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