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Full-Text Articles in Chemistry

A Dft Study On The Structural And Optical Properties And Cation Selectivities Of Some Metal-Coumarin-Crown Ether Complexes, Emi̇ne Esra Kasapbaşi, Mi̇ne Yurtsever Jan 2012

A Dft Study On The Structural And Optical Properties And Cation Selectivities Of Some Metal-Coumarin-Crown Ether Complexes, Emi̇ne Esra Kasapbaşi, Mi̇ne Yurtsever

Turkish Journal of Chemistry

Macrocyclic ethers are well-known molecules because of their high cation-binding capacities. They form stable complexes with alkaline and soil alkaline metals through strong oxygen bridges in solution. For enhanced optical properties, a new series of crown ethers was synthesized with a coumarin ring fused to it. The effects of the position of the coumarin ring, the type of the substituent on the coumarin ring, and the size of the crown on the optical properties of the material were studied according to the density functional theory (DFT) method at the B3LYP/6-31g(d) level of theory in the gas phase as well as …


One-Pot Synthesis Of Fully Substituted 1,3,4-Oxadiazole Derivatives From Aromatic Carboxylic Acids, Cyclobutanone And N-Isocyaniminotriphenylphosphorane, Mohsen Valizadeh Holagh, Abel Mohammadali Oglu Maharramv, Mirza Aliakbar Oglu Allahverdiyev, Ali Ramazani, Yavar Ahmadi, Ali Souldozi Jan 2012

One-Pot Synthesis Of Fully Substituted 1,3,4-Oxadiazole Derivatives From Aromatic Carboxylic Acids, Cyclobutanone And N-Isocyaniminotriphenylphosphorane, Mohsen Valizadeh Holagh, Abel Mohammadali Oglu Maharramv, Mirza Aliakbar Oglu Allahverdiyev, Ali Ramazani, Yavar Ahmadi, Ali Souldozi

Turkish Journal of Chemistry

Reactions of N-isocyaniminotriphenylphosphorane with cyclobutanone in the presence of aromatic (or heteroaromatic) carboxylic acids proceeded smoothly at room temperature and in neutral conditions to afford sterically congested 1-(5-aryl-1,3,4-oxadiazol-2-yl)- 1-cyclobutanol derivatives in high yields. The reaction proceeded smoothly and cleanly under mild conditions and no side reactions were observed. The structures of the products were deduced from their IR, ^1HNMR, and ^{13}CNMR spectra, and mass spectrometry.


Synthesis, Characterization, And Microwave-Promoted Catalytic Activity Of Novel Benzimidazole Salts Bearing Silicon-Containing Substituents In Heck-Mizoroki And Suzuki-Miyaura Cross-Coupling Reactions Under Aerobic Conditions, Hasan Küçükbay, Ni̇hat Şi̇reci̇, Ülkü Yilmaz, Selma Deni̇z, Mehmet Akkurt, Zeli̇ha Baktir, Orhan Büyükgüngör Jan 2012

Synthesis, Characterization, And Microwave-Promoted Catalytic Activity Of Novel Benzimidazole Salts Bearing Silicon-Containing Substituents In Heck-Mizoroki And Suzuki-Miyaura Cross-Coupling Reactions Under Aerobic Conditions, Hasan Küçükbay, Ni̇hat Şi̇reci̇, Ülkü Yilmaz, Selma Deni̇z, Mehmet Akkurt, Zeli̇ha Baktir, Orhan Büyükgüngör

Turkish Journal of Chemistry

A number of benzimidazole derivatives (1-8) were synthesized and the catalytic activity of these compounds in a catalytic system including Pd(OAc)_2 and K_2CO_3 in DMF-H_2O was evaluated in Heck-Mizoroki and Suzuki-Miyaura cross-coupling reactions of aryl iodides, bromides, and chlorides with styrene and arylboronic acids under microwave irradiation and aerobic conditions. The yields of both the Heck-Mizoroki and the Suzuki-Miyaura cross coupling reactions with aryl iodides and aryl bromides were nearly quantitative. The synthesized 1-substituted benzimidazole (1) and benzimidazole salts (2-8) were identified by ^1H- and ^{13}C-NMR and IR spectroscopic methods, and micro analysis. The molecular structure of 7 was also …


Synthesis And Evaluation Of Enzyme Inhibitory Potential Of Some Derivatives Of Scopolamine, Durre Shahwar, Muhammad Asam Raza, Tania Khan Jan 2012

Synthesis And Evaluation Of Enzyme Inhibitory Potential Of Some Derivatives Of Scopolamine, Durre Shahwar, Muhammad Asam Raza, Tania Khan

Turkish Journal of Chemistry

This study was designed to synthesize and evaluate derivatives of scopolamine (1) as acetylcholine esterase and protease inhibitors. Scopolamine (1) was extracted from the aerial parts of Datura innoxia through bioassay guided fractionation. Five different derivatives of scopolamine (1) were synthesized, and identified through spectroscopic studies. Their acetylcholine esterase (AChE) and trypsin inhibitory potentials were determined through standard protocols and evaluated from the perspective of structure-activity relationship. The synthesized scopolamine derivatives (2-6) showed remarkable AChE inhibitory activity, except for scopoline (6). The results showed higher enzyme inhibition potential of the synthesized compounds (2-5) as compared to scopolamine (1). Maximum inhibition …


^{99m}Tc Labeled Levofloxacin As An Infection Imaging Agent: A Novel Method For Labeling Levofloxacin Using Cysteine\Cdot Hcl As Co-Ligand And In Vivo Study, Syed Ali Raza Naqvi, Malik Muhammad Ishfaq, Zulfiqar Ali Khan, Saeed Ahmad Nagra, Iftikhar Hussain Bukhari, Abdullah Ijaz Hussain, Nasir Mahmood, Sohail Anjum Shahzad, Asma Haque, Tanveer Hussain Bokhari Jan 2012

^{99m}Tc Labeled Levofloxacin As An Infection Imaging Agent: A Novel Method For Labeling Levofloxacin Using Cysteine\Cdot Hcl As Co-Ligand And In Vivo Study, Syed Ali Raza Naqvi, Malik Muhammad Ishfaq, Zulfiqar Ali Khan, Saeed Ahmad Nagra, Iftikhar Hussain Bukhari, Abdullah Ijaz Hussain, Nasir Mahmood, Sohail Anjum Shahzad, Asma Haque, Tanveer Hussain Bokhari

Turkish Journal of Chemistry

Levofloxacin was labeled with ^{99m}Tc using cysteine\cdot HCl as co-ligand and SnCl_2.2H_2O as reducing agent. The influence of various parameters such as amount of cysteine\cdot HCl, reducing agent, pH value, and reaction time on labeling process was studied. After optimizing the conditions the labeling was performed at pH 5 using 1 mg of levofloxacin, 500 \mu g of cysteine\cdot HCl, 50 \mu g of SnCl_2.2H_2O, and 15 min reaction time. The radiochemical purity was determined with the help of instant thin layer chromatography (ITLC) and reverse phase high performance liquid chromatography (RP-HPLC) which was more than 95% and was stable …


Synthesis Of Some New Urea And Thiourea Derivatives And Evaluation Of Their Antimicrobial Activities, Yildiz Gülkok, Tuba Bi̇çer, Fatma Kaynak Onurdağ, Selda Özgen, Mustafa Fethi̇ Şahi̇n, Deni̇z Songül Doğruer Jan 2012

Synthesis Of Some New Urea And Thiourea Derivatives And Evaluation Of Their Antimicrobial Activities, Yildiz Gülkok, Tuba Bi̇çer, Fatma Kaynak Onurdağ, Selda Özgen, Mustafa Fethi̇ Şahi̇n, Deni̇z Songül Doğruer

Turkish Journal of Chemistry

In the present study, 18 new compounds were synthesized, 9 of which were urea (9a-e, 10a-d) while the others were thiourea (11a-e, 12a-d) derivatives. These derivatives were prepared by the reaction of 6-amino-5-nonsubstituted/chloro-3-methyl-2(3H)- benzoxazolones used as key intermediates with the appropriate isocyanates and isothiocyanates. The chemical structures of new compounds were confirmed by ^1H-NMR, mass, and elemental analysis. The synthesized compounds were screened for their antibacterial and antifungal activities against some pathogenic strains. Compounds 9a, 9b, 9e, 10a, and 10c, urea derivatives, and compounds 12a and 12d, thiourea derivatives, exhibited a relatively good inhibitory profile against E. coli, with a …


Antimicrobial Properties And Dna Interactions Studies Of 3-Hetarylazoquinoline-2,4-Diol Compounds, Fatma Öztürk, Leyla Açik, İzzet Şener, Fi̇kret Karci, Emi̇ne Kiliç Jan 2012

Antimicrobial Properties And Dna Interactions Studies Of 3-Hetarylazoquinoline-2,4-Diol Compounds, Fatma Öztürk, Leyla Açik, İzzet Şener, Fi̇kret Karci, Emi̇ne Kiliç

Turkish Journal of Chemistry

The purpose of the present study was to evaluate the antimicrobial effects of 3-hetarylazoquinoline-2,4-diols (19), having substituted or unsubstituted thiazole, benzothiazole, benzimidazole, triazole, isoxazole, and thiadiazole moieties at the 3-position, on bacterial and yeast strains. In addition, compounds and DNA interaction with pUC18 plasmid DNA were studied. The biological effects of these molecules were compared with potential antibiotics ampicillin,~chloramfenicol (for bacteria), and ketoconozole (for yeast). According to the results, all compounds except 8 have mild to moderate activity against some of the bacterial strains tested, and none of the compounds have activity against the fungi C. tropicalis and C. albicans. …


Polymers From Renewable Resources: Synthesis And Characterization Of Poly(2,5-Dihydro-2,5-Dimethoxy Furan), Hakan Çi̇ftçi̇, Zeki̇ Öktem, Hasan Nur Testereci̇ Jan 2012

Polymers From Renewable Resources: Synthesis And Characterization Of Poly(2,5-Dihydro-2,5-Dimethoxy Furan), Hakan Çi̇ftçi̇, Zeki̇ Öktem, Hasan Nur Testereci̇

Turkish Journal of Chemistry

The cationic polymerization of cis, trans-2,5-dihydro-2,5-dimethoxy furan (DHMF) was studied in the presence of HClO_4, in acetonitrile. Different reaction parameters were investigated such as initiator concentration and temperature with duration. Obtained polymers were soluble in dimethylsulfoxide (DMSO) and dimethylformamide (DMF) and the M_n value was calculated as 2700 g/mol by cryoscopy. The FT-IR and ^1H-NMR results indicate that the polymerization proceeds via ring opening. Thermal properties were studied by DSC and TGA.


Simultaneous Determination Of Cr(Iii) And Cr(Vi) Using Differential Pulse Polarography And Application To Gerede River, Olcay Şendi̇l, Nabeel Mohammed, Güler Somer Jan 2012

Simultaneous Determination Of Cr(Iii) And Cr(Vi) Using Differential Pulse Polarography And Application To Gerede River, Olcay Şendi̇l, Nabeel Mohammed, Güler Somer

Turkish Journal of Chemistry

Determination of Cr(III) in the presence of Cr(VI) from one polarogram is not easy. No such procedure was found in the literature. In polarographic studies Cr(III) had a peak only in acidic medium, while Cr(VI) had either 1 or 2 peaks in both acidic and basic solutions. In solutions that contain these 2 ions, the peak obtained in acidic medium for Cr(III) will be the sum of both ions. Thus, Cr(III) cannot be determined directly from one polarogram. In this work, a new and simple polarographic method is established for the determination of Cr(III) and Cr(VI) by using only one …


Synthesis And Antimicrobial Evaluation Of Some Annelated Phthalazine Derivatives And Acyclo C-Nucleosides From 1-Chloro-4-(2,4,6-Trimethylphenyl) Phthalazine Precursor, Maher Abdel Aziz El-Hashash, Ahmed Youssef Soliman, Ibrahim Essam Elshamy Jan 2012

Synthesis And Antimicrobial Evaluation Of Some Annelated Phthalazine Derivatives And Acyclo C-Nucleosides From 1-Chloro-4-(2,4,6-Trimethylphenyl) Phthalazine Precursor, Maher Abdel Aziz El-Hashash, Ahmed Youssef Soliman, Ibrahim Essam Elshamy

Turkish Journal of Chemistry

A highly efficient and versatile synthetic approach to the synthesis of annelated phthalazine derivatives viz. 1,2,4-triazolo [3,4-a]phthalazine 11a,b, 14, 18, 19a,b, 29-31, 33, 1,2,4-triazino [3,4-a]phthalazine 25a,b-28, 1,3,5-triazino[4,3-a]phthalazine 22, tetrazolo[5,1-a] phthalazine 23, imidazophthalazine 9a,b,15, and pyrimidinophthlazine 6, 10, 16, 17, 20 is presented. Moreover, acyclo C-nucleoside and double headed acyclo C-nucleoside of 1,2,4-triazolo[3,4-a]phthalazine 12, 13 were obtained via heterocyclization reaction of 1-chloro-4-(2,4,6-trimethylphenyl) phthalazine (4) with gluconic acid hydrazide and galactaric acid bis hydrazide, respectively. The new compounds were synthesized with the objective of studying their antimicrobial activity.


Synthesis, Anti-Inflammatory, Antiplatelet And In Silico Evaluations Of (E)-3-(3-(2,3-Dihydro-3-Methyl-2-Oxo- 3h-Benzoxazole-6-Yl)-1-Phenyl-1h-Pyrazole- 4-Yl)Acrylamides, Sultan Baytaş, Ni̇lüfer Nermi̇n Turan Dural, Yeşi̇m Özkan, Hasan Bolkan Şi̇mşek, Türki̇z Gürsel, Serdar Ünlü Jan 2012

Synthesis, Anti-Inflammatory, Antiplatelet And In Silico Evaluations Of (E)-3-(3-(2,3-Dihydro-3-Methyl-2-Oxo- 3h-Benzoxazole-6-Yl)-1-Phenyl-1h-Pyrazole- 4-Yl)Acrylamides, Sultan Baytaş, Ni̇lüfer Nermi̇n Turan Dural, Yeşi̇m Özkan, Hasan Bolkan Şi̇mşek, Türki̇z Gürsel, Serdar Ünlü

Turkish Journal of Chemistry

A series of (E)-3-(3-(2,3-dihydro-3-methyl-2-oxo-3H-benzoxazole- 6-yl)-1-phenyl-1H-pyrazole-4-yl)acry- lamides (7a--k) were synthesized and evaluated for their in vitro inhibitory activities on COX-1 and COX-2 isoforms using a human whole blood assay as well as their antiplatelet profile against human platelet aggregation using arachidonic acid as agonists. Among the synthesized derivatives 7a--k, especially compound 7g exhibited dual anti-inflammatory and antiplatelet activity with selective COX-2 inhibition.


Competitive Hydrogen Bonding In Aspirin-Aspirin And Aspirin-Leucine Interactions, Zeynep Yurtsever, Burak Erman, İsmai̇l Ersi̇n Yurtsever Jan 2012

Competitive Hydrogen Bonding In Aspirin-Aspirin And Aspirin-Leucine Interactions, Zeynep Yurtsever, Burak Erman, İsmai̇l Ersi̇n Yurtsever

Turkish Journal of Chemistry

Aspirin-aspirin and aspirin-leucine interactions are studied by the density functional theory (DFT) and high level ab initio calculations with second order Moller-Plesset perturbation theory (MP2). The rotational isomers of aspirin are identified by their relative stability both in gaseous phase and in water using the polarizable continuum method (PCM). Local minima of aspirin monomers in water are found to be all highly populated compared to the gas phase behavior. Homodimers of aspirin form hydrogen bonds with bond energies of 10 kcal/mol. Weak hydrogen bonds utilizing phenyl and methyl groups are also found. The interaction between aspirin and leucine is stronger …


Copolymerization Of N-Vinyl Pyrrolidone With Methyl Methacrylate By Ti(Iii)-Dmg Redox Initiator, Ajithkumar Manayan Parambil, Yashoda Malagar Puttaiahgowda, Prasannakumar Shankarappa Jan 2012

Copolymerization Of N-Vinyl Pyrrolidone With Methyl Methacrylate By Ti(Iii)-Dmg Redox Initiator, Ajithkumar Manayan Parambil, Yashoda Malagar Puttaiahgowda, Prasannakumar Shankarappa

Turkish Journal of Chemistry

Redox copolymerization of N-vinyl-2-pyrrolidone (NVP) with methyl methacrylate (MMA) was carried out using titanium(III)-- dimethylglyoxime [Ti(III)-DMG] redox initiator in aqueous sulfuric acid-alcohol media. The resulting copolymer was characterized by FTIR, ^1H-NMR, and ^{13}C-NMR spectroscopic methods and elemental analysis. Thermal properties of the copolymer were determined by differential scanning calorimetric technique and thermogravimetric analysis. The reactivity ratios of the monomers were computed by Fineman-Ross, Kelen-Tudos, and extended Kelen-Tudos methods at lower conversion. The reactivity ratios obtained r_1 (MMA) 1.69 and r_2 (NVP) 0.03 showed richer content of MMA than NVP in the copolymer having extreme ideal behavior. The distribution of monomer …


Design And Synthesis Of New 1,2,4-Triazole Derivatives Containing Morpholine Moiety As Antimicrobial Agents, Deni̇z Şahi̇n, Hacer Bayrak, Ahmet Demi̇rbaş, Nesli̇han Demi̇rbaş, Şengül Alpay Karaoğlu Jan 2012

Design And Synthesis Of New 1,2,4-Triazole Derivatives Containing Morpholine Moiety As Antimicrobial Agents, Deni̇z Şahi̇n, Hacer Bayrak, Ahmet Demi̇rbaş, Nesli̇han Demi̇rbaş, Şengül Alpay Karaoğlu

Turkish Journal of Chemistry

2-Morpholine-4ylethyl-3H-1,2,4-triazole-3-ones (2a, 2b) were obtained from the condensation between the corresponding ethoxycarbonylhydrazones and 2-morpholinoethanamine. 2a was converted to acetohydrazide (4) via the formation of an ester derivative (3). Treatment of 2a and 2b with several aryl sulfonyl chlorides afforded the corresponding 2-arylsulfonyl-1,2,4-triazole-3-ones (5a-c and 6). The reaction of hydrazide (4) with benzyl iso- and benzyl isothiocyanate produced the corresponding carboxamide (8a) and carbothioamide (8b). The basic treatment of 8b yielded 5-mercapto-4H-1,2,4-triazol-3-yl)methyl]-2,4-dihydro-3H-1,2,4-triazol-3-one (10). The synthesis of 1,3-thiazol-2(3H)-ylidene-1,2,4-triazol-1- ylacetohydrazide (11) and 1,3-oxazole-2(3H)-ylidene-1,2,4-triazole- 1-yl)acetohydrazide (9) derivatives was performed from the reaction of 8a and 8b with substituted phenacyl bromides. All the newly synthesized …


Synthesis, Characterization, And Antioxidant Activities Of New Trisubstituted Triazoles, Kemal Sancak, Yasemi̇n Ünver, Di̇lek Ünlüer, Esra Düğdü, Gülcan Kör, Fati̇h Çeli̇k, Emrah Bi̇ri̇nci̇ Jan 2012

Synthesis, Characterization, And Antioxidant Activities Of New Trisubstituted Triazoles, Kemal Sancak, Yasemi̇n Ünver, Di̇lek Ünlüer, Esra Düğdü, Gülcan Kör, Fati̇h Çeli̇k, Emrah Bi̇ri̇nci̇

Turkish Journal of Chemistry

A series of new 4-(3,4dimethoxyphenethyl)-3,5-akyl/aryl-4H- 1,2,4-triazoles (3a-g) were obtained by reaction of ethyl N'-(alkylidene/arylidene)hydrazonate (1) and 2-(3,4-dimethoxy phenyl)ethanamine (2). Compounds 4d, e, and g were synthesized from the reaction of corresponding compounds 3d, e, and g with BBr_3, respectively. The 10 new compounds synthesized were characterized by elemental analyses, IR, ^1H-NMR, and ^{13}C-NMR spectral data. The structure of compound 3g was inferred through IR, ^1H-, ^{13}C-NMR, elemental analyses, and X-ray spectral techniques. In addition, the newly synthesized chemicals were screened for their antioxidant properties. Among the chemicals tested, 4d, e, and g exhibited the highest degree of antioxidant activity.


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.


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.


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) …


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 …


Titrimetric Determination Of Anionic Surfactant Content In Anionic/Nonionic Surfactant Mixture Solution By Anionic Surfactant Selective Electrode, Junwei Wang, Zhiping Du, Wanxu Wang, Wei Xue Jan 2012

Titrimetric Determination Of Anionic Surfactant Content In Anionic/Nonionic Surfactant Mixture Solution By Anionic Surfactant Selective Electrode, Junwei Wang, Zhiping Du, Wanxu Wang, Wei Xue

Turkish Journal of Chemistry

A new polyvinyl chloride (PVC) membrane electrode for determining the concentration of sodium dodecylsulfate (SDS) based on a neutral ion pair complex of dodecyltrimethylammonium-dodecylsulfate (DTA^+DS^-) as ionophore is described in this paper. The construction and characteristic performance of the PVC membrane electrode displays a Nernstian slope of --56.9 \pm 0.3 mV/decade in the concentration range of 2.0 \times 10^{-6} to 3.2 \times 10^{-3} mol L^{-1} and a detection limit of 1.6 \times 10^{-6} mol L^{-1}. The lifetime of the electrode is more than 3 months without showing significant change in the values of slope or linear concentration range. The electrode …


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 …


Determination Of Ultratrace Amounts Of Dichloro-Nitrobenzene And Dichloro-Nitroaniline In Water Samples Using Solidified Floating Organic Drop Microextraction (Sfodme) And Gas Chromatography, Shayessteh Dadfarnia, Mohammad Mirzaei, Ali Mohammad Haji Shabani, Batoul Ramazanzadeh Jan 2012

Determination Of Ultratrace Amounts Of Dichloro-Nitrobenzene And Dichloro-Nitroaniline In Water Samples Using Solidified Floating Organic Drop Microextraction (Sfodme) And Gas Chromatography, Shayessteh Dadfarnia, Mohammad Mirzaei, Ali Mohammad Haji Shabani, Batoul Ramazanzadeh

Turkish Journal of Chemistry

Solidified floating organic drop microextraction (SFODME) in combination with gas chromatography with an electron capture detector was used for separation/enrichment and determination of 2,5-dichloro-nitrobenzene, 2,3-dichloro-nitrobenzene, and 2,6-dichloro-4-nitroaniline in water samples. The main parameters affecting the performance of SFOME, such as solvent volume, extraction time, stirring rate, extraction temperature, sample volume, nature of the solvent and ionic strength were optimized. Under the optimum experimental conditions, good relative standard deviations of 7.5%, 6.9%, and 9.3% for 7 extractions and determination of 50 ng L^{-1} of 2,5-dichloro-nitrobenzene, 2,3-dichloro-nitrobenzene and 2,6-dichloro-4-nitroaniline were obtained, respectively. Enrichment factors of 1390, 1398, and 1362 and detection limits …


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.


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 …


A One-Pot Efficient Four-Component Reaction For The Synthesis Of 2-(Arylamino)-2-(5-Aryl-1-Ethenyl-1,3,4-Oxadiazol-2-Yl)Propyl Benzoate (Or 4-Bromobenzoate) Derivatives, Mohsen Valizadeh Holagh, Abel Mohammadali Oglu Maharramov, Mirza Aliakbar Oglu Allahverdiyev, Ali Ramazani, Yavar Ahmadi, Fatemeh Zeinali Nasrabadi, Ali Souldozi Jan 2012

A One-Pot Efficient Four-Component Reaction For The Synthesis Of 2-(Arylamino)-2-(5-Aryl-1-Ethenyl-1,3,4-Oxadiazol-2-Yl)Propyl Benzoate (Or 4-Bromobenzoate) Derivatives, Mohsen Valizadeh Holagh, Abel Mohammadali Oglu Maharramov, Mirza Aliakbar Oglu Allahverdiyev, Ali Ramazani, Yavar Ahmadi, Fatemeh Zeinali Nasrabadi, Ali Souldozi

Turkish Journal of Chemistry

Reactions of N-isocyaniminotriphenylphosphorane with 2-oxopropyl benzoate (or 2-oxopropyl 4-bromobenzoate) in the presence of 3-phenyl-2-propynoic acid and primary amines proceeded smoothly at room temperature and in neutral conditions to afford sterically congested 1,3,4-oxadiazole derivatives in high yields. The reaction proceeded smoothly and cleanly under mild conditions and no side reactions were observed.


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.


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 …


Synthesis And Characterization Of Bis(Azine) Ligands And Metal Complexes: Dna-Interaction And Extraction Properties For Metals And Dichromate Anions, Sultan Kulaksizoğlu, Cansu Gökçe, Ramazan Güp Jan 2012

Synthesis And Characterization Of Bis(Azine) Ligands And Metal Complexes: Dna-Interaction And Extraction Properties For Metals And Dichromate Anions, Sultan Kulaksizoğlu, Cansu Gökçe, Ramazan Güp

Turkish Journal of Chemistry

Two new bis(bidentate) azine ligands were prepared by linking (1Z,1'Z)-1,1'-{butane-1,4-diylbis[oxyben-zene-4,1- diyl(1Z)eth-1-yl-1-ylidene]}dihydrazine to salicylaldehyde and pyridine-2-carbaldehyde, 1,4-bis{4-{(1E)-1-((2E)-(2- hydroxybenzene--2-ylmethy-lidene)hydrazonylidene)ethyl}phenoxy}butane (H_2L^1), and 1,4-bis{4-{(1E)-1-((2E)-(pyridine--2-ylmethylidene) hydrazonylidene)ethyl}phenoxy}butane (L^2), respecti- vely. Two kinds of copper(II) and nickel(II) complexes with different ligands were prepared. Reaction of H_2L^1 with Cu(II) and Ni(II) acetate with 1:1 molar ratio gave double stranded binuclear bis(azine) complexes with stoichiometry [M(L^1)]_2 containing {M^{II}N_2O_2} centers. On the other hand, 1:1 molar ratio reaction of Cu(II) and Ni(II) chloride with L^2 yielded mononuclear metal complexes with general stoichiometry [M(L^2)Cl_2] containing {M^{II}N_2N_2} centers. The structures of both bis(azine) ligands and complexes were identified by elemental analysis, infrared …


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.


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.