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2011

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Articles 751 - 780 of 1068

Full-Text Articles in Chemistry

Catalytic Activity Of Titania And Titania-Containing Nanomaterials: And, Spatial Distribution Of Silica Surface Groups Using A Tethered Amine Catalyst, Ramkumar Samala Jan 2011

Catalytic Activity Of Titania And Titania-Containing Nanomaterials: And, Spatial Distribution Of Silica Surface Groups Using A Tethered Amine Catalyst, Ramkumar Samala

Masters Theses

Titania and titania-containing nanomaterials are semiconductor photocatalysts and are widely used to degrade (i.e. oxidize) organic matter. The adsorption and catalytic properties of highly dispersed titania prepared using sulfate and pyrogenic methods, and fumed containing mixed oxides, were studied using catalytic decomposition of methylene blue primarily by kinetic methods. Commercial ultrafine titania (PC-100, PC-105 and PC-500), fumed Ti 02, and the mixed oxide of 80% Silica/20% Titania (ST20) were studied. Catalytic activity as measured by methylene blue decomposition kinetics was highest per gram for non-treated ultrafine titania PC- 500 which has the highest SsET and smallest particle size. However this …

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Fourier Transform Mass Spectrometry For The Molecular Level Characterization Of Natural Organic Matter: Instrument Capabilities, Applications, And Limitations, Rachel L. Sleighter, Patrick G. Hatcher, Goran Nikolić (Ed.) Jan 2011

Fourier Transform Mass Spectrometry For The Molecular Level Characterization Of Natural Organic Matter: Instrument Capabilities, Applications, And Limitations, Rachel L. Sleighter, Patrick G. Hatcher, Goran Nikolić (Ed.)

Chemistry & Biochemistry Faculty Publications

No abstract provided.

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Characterization Of Heterogeneities And Domains In Aquatic And Sedimentary Organic Matter By 1 H Spin Diffusion: Potential For Elucidating The Formation Mechanisms, Jingdong Mao, Xiaoyan Cao Jan 2011

Characterization Of Heterogeneities And Domains In Aquatic And Sedimentary Organic Matter By 1 H Spin Diffusion: Potential For Elucidating The Formation Mechanisms, Jingdong Mao, Xiaoyan Cao

Chemistry & Biochemistry Faculty Publications

Although the information on domains and heterogeneities of natural organic matter (NOM) can provide insights into its formation mechanisms, the appropriate solid-state NMR technique for measuring them is still lacking. The traditional technique requires mobility differences in NOM whereas NOM components are primarily rigid. We introduced a new 1H spin diffusion technique, 1H-13C two-dimensional heteronuclear correlation (2D HETCOR) NMR with 1H spin diffusion, for characterization of domains and heterogeneities in aquatic and sedimentary organic matter. It was achieved by collecting a series of 2D HETCOR spectra with a variable mixing time, tm', and …

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Reaction Of Cycloheptatriene Derivatives With 1,3-Diketones In The Presence Of Mn(Oac)_3, Mahi̇r Burak Südemen, Mustafa Zengi̇n, Hayri̇ye Genç, Meti̇n Balci Jan 2011

Reaction Of Cycloheptatriene Derivatives With 1,3-Diketones In The Presence Of Mn(Oac)_3, Mahi̇r Burak Südemen, Mustafa Zengi̇n, Hayri̇ye Genç, Meti̇n Balci

Turkish Journal of Chemistry

The reactions of some 1,3-dicarbonyl compounds with cycloheptatriene derivatives in the presence of Mn(OAc)_3 were examined. Cycloheptatriene forms mainly [2+3] and [6+3] dihydrofuran addition products derived from cycloheptatriene. However, the reaction of acetylacetone with cycloheptatriene substituted with an electron withdrawing group exclusively gave products derived from the norcaradiene structure. The formation mechanism of the products as well as the role of the substituent attached to cycloheptatriene is discussed.

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Reaction Dynamics Of Br + Hd: Quantum Wave Packet On Three Potential Energy Surfaces, Qing Song, Wei-Long Quan, Tian-Jun Feng Jan 2011

Reaction Dynamics Of Br + Hd: Quantum Wave Packet On Three Potential Energy Surfaces, Qing Song, Wei-Long Quan, Tian-Jun Feng

Turkish Journal of Chemistry

The initial state-resolved reaction probabilities, reaction cross-sections, and rate constants of the reaction Br + HD are computed on 3 potential energy surfaces (denoted as e-LEPS, MB2, and MB3, respectively) by carrying out quantum time-dependent wave packet calculations. The results show that the reactivity of Br + HD on MB3 is much stronger than that on e-LEPS and somewhat weaker than that on MB2. Both of the vibrational and the rotational excitation of reagent HD enhance the reaction, which depends on the PESs and the strongest enhancement effects are on e-LEPS.

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Azocalixarenes.7: Synthesis And Study Of The Absorption Properties Of Novel Mono-Azo Substituted Chromogenic Calix[4]Arenes, Hasaletti̇n Deli̇göz, Özlem Özen Karakuş Jan 2011

Azocalixarenes.7: Synthesis And Study Of The Absorption Properties Of Novel Mono-Azo Substituted Chromogenic Calix[4]Arenes, Hasaletti̇n Deli̇göz, Özlem Özen Karakuş

Turkish Journal of Chemistry

Eight new mono-azo substituted chromogenic calix[4]arenes (1-8) were synthesized by diazo-coupling reactions in which 25,26,27-tribenzoyloxy-28-hydroxy-5,11,17-tri-(tert-butyl)calix[4]arene and diazonium salts (2-, 3-, and 4-nitroaniline; 4-phenyl azoaniline; 3- and 4-chloroaniline; or 2- and 4-methylaniline) formed the corresponding mono-azo substituted derivatives in high yields. The mono-azo substituted calix[4]arenes were characterized by UV-Vis, FT-IR, and ^1H-NMR spectroscopic techniques. Elemental analysis was also carried out. In addition, the effects of varying pH levels and solvents upon the absorption ability of azocalix[4]arenes substituted with electron-donating and electron-withdrawing groups at their o-, m-, and p- positions were studied. The results proved that the absorption maxima of the prepared …

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Synthesis And Biological Activity Of 5-Substituted-2-Amino-1,3,4-Oxadiazole Derivatives, Sanjeev Kumar Jan 2011

Synthesis And Biological Activity Of 5-Substituted-2-Amino-1,3,4-Oxadiazole Derivatives, Sanjeev Kumar

Turkish Journal of Chemistry

Electrical energy offers numerous benefits for performing synthesis, including increased reaction rates, enhanced yields, and cleaner chemistries. 5-Substituted-2-amino-1,3,4-oxadiazoles were synthesized directly from the semicarbazone at a platinum electrode under controlled potential electrolysis in an undivided cell assembly in acetonitrile. The compounds were screened for antibacterial and antifungal activity against Staphylococcus aureus, Klebsiella pneumoniae, Pellicularia salmonicolor, and Macrophomina phaseolina.

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Synthesis And Antiinflammatory Activity Of Novel 2,5-Disubstituted Thiophene Derivatives, Sahar Badr Jan 2011

Synthesis And Antiinflammatory Activity Of Novel 2,5-Disubstituted Thiophene Derivatives, Sahar Badr

Turkish Journal of Chemistry

New series of 2,5-disubstituted thiophenes were synthesized. Thiosemicarbazones 1a-b were reacted with various reagents, such as diethyl-2-bromomalonate, ethyl-2-chloroacetoacetate, thioglycolic acid, 4-substituted phenacyl bromides, and acetic anhydride, to afford heterocyclic substituted thiophene derivatives 2a-b, 3a-b, 4a-b, 5a-b, 6a-b, and 7a-b, respectively. Moreover, cyclization of the key intermediate 1b with chloroacetic acid yielded thiazolidine 9, which on reaction with appropriate aromatic aldehydes afforded the corresponding arylidene derivatives 10a-f. Finally, reaction of N^\-arylidene cyanoacetohydrazide 11 with sulfur and phenylisothiocyanate yielded thiazoline derivative 12, which on treatment with triethylorthoformate and acetic anhydride afforded thiazolo[4,5-d]pyrimidinone derivative 13. Some of the newly synthesized compounds showed promising …

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Antimicrobial Activity And Volatile Constituents Of The Flower, Leaf, And Stem Of Paeonia Daurica Grown In Turkey, Gonca Tosun, Nuran Kahri̇man, Canan Albay, Şengül Alpay Karaoğlu, Nuretti̇n Yayli Jan 2011

Antimicrobial Activity And Volatile Constituents Of The Flower, Leaf, And Stem Of Paeonia Daurica Grown In Turkey, Gonca Tosun, Nuran Kahri̇man, Canan Albay, Şengül Alpay Karaoğlu, Nuretti̇n Yayli

Turkish Journal of Chemistry

The volatile constituents of the essential oils from the flower, leaf, and stem of Paeonia daurica Andrews were analyzed by GC and GC-MS. A total of 74 compounds were identified, constituting over 95.0%, 80.8%, and 98.2% of the oil composition of the flower, leaf, and stem of P. daurica, respectively. Aldehydes were shown to be the main group of constituents of the flower and stem parts, at 39.1% and 79.8%, respectively. However, the major group in the leaf oil was found to be oxygenated monoterpenes (43.5%). Salicylaldehyde (20.7% and 79.5%) was the major component of the flower and stem oils …

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Synthesis And Characterization Of Novel Benzovesamicol Analogs, Thaer Assaad Jan 2011

Synthesis And Characterization Of Novel Benzovesamicol Analogs, Thaer Assaad

Turkish Journal of Chemistry

Three new racemic vesamicol analogs were successfully prepared in good yields and high purity. All compounds were characterized by both IR and NMR spectroscopy. Compounds (\pm)-5 and (\pm)-6 showed a moderate lipophilicity compared with reference compounds IBVM and DRC140, respectively. However, the lipophilicity of DRC140 and (\pm)-9 showed very similar behaviors.

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Polarographic Determination Of Anticancer Drug Vitamin K_3 With Direct And Indirect Methods/Application To Serum And K_3 Injection Solution, Ümmi̇han Taşkoparan Yilmaz, Güler Somer Jan 2011

Polarographic Determination Of Anticancer Drug Vitamin K_3 With Direct And Indirect Methods/Application To Serum And K_3 Injection Solution, Ümmi̇han Taşkoparan Yilmaz, Güler Somer

Turkish Journal of Chemistry

In this work, direct and indirect methods for determination of vitamin K_3 were developed using differential pulse polarography. The reaction between sulfite and the quinone (Q) form of vitamin K_3 was used for indirect determination, since the sulfite peak at -0.7 V is sharp and very reproducible in 0.1 M HAc NaAc (pH = 5.5). It was found that at pH 4.5-5.5, this reaction was quantitative and very fast when the temperature was 45 °C. For its direct determination, on the other hand, vitamin K_3 was standardized by the indirect method using standard sulfite as the reducing agent. The calibration …

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Synthesis And Spectral Characterization Of A Decavanadate/Chitosan Complex, Violeta Dimitrova Kassabova Zhetcheva, Lilyana Parvanova Pavlova Jan 2011

Synthesis And Spectral Characterization Of A Decavanadate/Chitosan Complex, Violeta Dimitrova Kassabova Zhetcheva, Lilyana Parvanova Pavlova

Turkish Journal of Chemistry

A decavanadate/chitosan complex was synthesized by crosslinking chitosan with decavanadate anions at a pH of 3. The materials were characterized by Fourier transformed infrared spectroscopy (FT-IR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), absorption spectroscopy (UV-Vis), and transmission electron microscopy (TEM). The spectroscopic results indicated that the decavanadate/chitosan complex was successfully obtained as result of an ionic crosslinking of the chitosan with decavanadate anions.

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Stability Study Of Passive Film On Copper Surface As A Function Of Anodic Potential, Amtul Naseer, Athar Yaseen Khan Jan 2011

Stability Study Of Passive Film On Copper Surface As A Function Of Anodic Potential, Amtul Naseer, Athar Yaseen Khan

Turkish Journal of Chemistry

Results for passive film formation and breakdown on copper disk electrodes in buffer solutions, pH 9.2 and 8.5, were reported earlier. The present studies were carried out in a buffer solution, pH 8.0, and together these studies make good material for understanding the effect of pH changes on film texture as a function of potential. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) were used to examine passive film and the variations it went through upon being treated potentiostatically in the range of -0.3 to 0.9 V. On the basis of equivalent circuits used for modeling impedance data in this …

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Preparation, Morphology, And Thermomechanical Properties Of Coal Ash/Polyethylene Oxide Composites, Khalid Saeed, Muhmmad Ishaq, Muhmmad Ilyas Jan 2011

Preparation, Morphology, And Thermomechanical Properties Of Coal Ash/Polyethylene Oxide Composites, Khalid Saeed, Muhmmad Ishaq, Muhmmad Ilyas

Turkish Journal of Chemistry

Coal ash/polyethylene oxide (ash/PEO) composite films were prepared by the solution casting technique. Scanning electron microscopy (SEM) micrographs indicated that the ash particles were dispersed and embedded well within the polymer matrix. The size of the ash particles in the PEO matrix was less than 3 \mu m. The polarized optical microscopic (POM) analyses revealed that the pure PEO, upon crystallization, showed distinct crystalline spherulites of a considerable size. The size of the spherulites was decreased by the incorporation of ash particles into the polymer matrix, which might be due to the nucleation role of ash in ash/PEO composite, and …

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Determination Of Stability Constants Of 5-(2-Hydroxybenzylidene)-2-Thioxodihydropyrimidine-4,6(1h,5h)-Dione With Copper(Ii) And Mercury(Ii) Ions, Morteza Bahram, Nader Noroozi Pesyan, Abdolhossein Naseri, Masomeh Tasbihforosh Jan 2011

Determination Of Stability Constants Of 5-(2-Hydroxybenzylidene)-2-Thioxodihydropyrimidine-4,6(1h,5h)-Dione With Copper(Ii) And Mercury(Ii) Ions, Morteza Bahram, Nader Noroozi Pesyan, Abdolhossein Naseri, Masomeh Tasbihforosh

Turkish Journal of Chemistry

In this work, a hard model chemometric method was used to determine the stability constants of copper(II) and mercury(II) complexes with the newly synthesized ligand 5-(2-hydroxybenzylidene)- 2-thioxodihydropyrimidine-4,6(1H,5H)-dione in acetonitrile by UV-Vis spectrophotometry. The ligand forms stable complexes with both metal cations. The protonation constants of the ligand were also measured in an ethanol-water (1:1) mixture.

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Synthesis And Properties Of New Optically Active And Organosoluble Poly(Ester-Imide)S Containing L-Valine Moieties In The Main Chain By Direct Polycondensation Reaction, Khalil Faghihi, Meisam Shabanian, Mohsen Hajibeygi Jan 2011

Synthesis And Properties Of New Optically Active And Organosoluble Poly(Ester-Imide)S Containing L-Valine Moieties In The Main Chain By Direct Polycondensation Reaction, Khalil Faghihi, Meisam Shabanian, Mohsen Hajibeygi

Turkish Journal of Chemistry

New optically active poly(ester-imide)s (PEIs) containing bicyclo[2,2,2]oct-7-ene-2,3,5,6-tetracarboxylic diimide in the main chain were prepared by the reaction of N,N'-(bicyclo[2,2,2]oct-7- ene-2,3,5,6-tetra carboxylic)-bis-L-valine 4 as a diacid monomer with various aromatic diols 5a-g in a system of tosyl chloride (TsCl), pyridine (Py), and N,N-dimethylformamide (DMF). The reactions with TsCl were significantly promoted by controlling alcoholysis with diols, in the presence of catalytic amounts of DMF, to give a series of optically active poly(ester-imide)s. The resulting new polymers were obtained in good yields and inherent viscosities, ranging between 0.36 and 0.62 dL g^{-1}, and were characterized with FT-IR and ^1H-NMR spectroscopy, including specific …

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Synthesis And Spectrophotometric Determination Of Acidity Constants Of 2,3,4,6'-Tetrahydroxy-3'-Sulfoazobenzene And Their Use In Determination Of Aluminum, Tufan Güray, Cemi̇l Öğreti̇r, Tevfi̇k Gedi̇kbey, Abu Ali̇ Hüseyi̇nli̇ Jan 2011

Synthesis And Spectrophotometric Determination Of Acidity Constants Of 2,3,4,6'-Tetrahydroxy-3'-Sulfoazobenzene And Their Use In Determination Of Aluminum, Tufan Güray, Cemi̇l Öğreti̇r, Tevfi̇k Gedi̇kbey, Abu Ali̇ Hüseyi̇nli̇

Turkish Journal of Chemistry

A novel azo derivative, 2,3,4,6'-tetrahydroxy-3'-sulfoazobenzene (THSA), was synthesized by using pyrogallol. The acid dissociation constants, or K_a values, of THSA were determined by the UV-visible spectroscopic technique. The protonation and deprotonation behaviors of the title molecule were studied from the super basic to the super acid region (i.e. 10 N NaOH to 98% H_2SO_4), including the pH region. A selective and sensitive UV-visible spectrophotometric method was devised for determination of aluminum by using this ligand. The developed method was successfully applied to an alunite mineral and to pharmaceutical preparations for the determination of aluminum.

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Synthesis And Anti-Helicobacter Pylori Activity Of (4-Nitro-1-Imidazolylmethyl)-1,2,4-Triazoles, 1,3,4-Thiadiazoles, And 1,3,4-Oxadiazoles, Asal Fallah-Tafti, Tahmineh Akbarzadeh, Parastoo Saniee, Farideh Siavoshi, Abbas Shafiee, Alireza Foroumadi Jan 2011

Synthesis And Anti-Helicobacter Pylori Activity Of (4-Nitro-1-Imidazolylmethyl)-1,2,4-Triazoles, 1,3,4-Thiadiazoles, And 1,3,4-Oxadiazoles, Asal Fallah-Tafti, Tahmineh Akbarzadeh, Parastoo Saniee, Farideh Siavoshi, Abbas Shafiee, Alireza Foroumadi

Turkish Journal of Chemistry

A series of [(4-nitro-1H-imidazol-1-yl)methyl]-1,2,4- triazoles and 1,3,4-thiadiazoles were prepared and evaluated for their activity against sensitive and resistant H. pylori strains. Study of the structure-activity relationship of these series of compounds indicated that the type of nitroimidazole moiety and the pendent group on the heteroaryl analog dramatically impact the anti-H. pylori activity. In triazole series, compound 5d, containing a 4-methyl phenyl group on the triazole ring, was the most potent compound tested against both metronidazole-sensitive and -resistant strains at a concentration of 8 \mu g.

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Molecular Modeling And Antimycobacterial Studies Of Mannich Bases: 5-Hydroxy-2-Methyl-4h-Pyran-4-Ones, Barkin Berk, Demet Us, Si̇nem Öktem, Zühtü Tanil Kocagöz, Berrak Çağlayan, Işil Aksan Kurnaz, Di̇lek Demi̇r Erol Jan 2011

Molecular Modeling And Antimycobacterial Studies Of Mannich Bases: 5-Hydroxy-2-Methyl-4h-Pyran-4-Ones, Barkin Berk, Demet Us, Si̇nem Öktem, Zühtü Tanil Kocagöz, Berrak Çağlayan, Işil Aksan Kurnaz, Di̇lek Demi̇r Erol

Turkish Journal of Chemistry

The World Health Organization lists tuberculosis among the top 3 leading causes of death from a single infectious agent, and reported cases of multidrug-resistant tuberculosis (MDR-TB) are on the rise. In an attempt to improve MDR-TB drug-directed therapy, we synthesized 11 4-substituted piperazine derivatives of 3-hydroxy-6-methyl-4H-pyran-4-one pharmacophore by reacting 5-hydroxy-2-methyl-4H-pyran-4-one with suitable piperazine derivatives under Mannich reaction conditions. Inhibitory effects of the 11 compounds on Escherichia coli DNA gyrase were evaluated via DNA gyrase supercoiling assay. The minimum inhibitory concentrations (MIC) of the 11 compounds and 41 compounds from our previous studies against Mycobacterium tuberculosis H37RV were assessed, in vitro, …

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Synthesis And In Vitro Antimycobacterial Activities Of Novel 6-Substituted-3(2h)-Pyridazinone-2-Acetyl-2-(Substituted/ Nonsubstituted Acetophenone) Hydrazone, Semra Utku, Mehtap Gökçe, Gönül Aslan, Gül Bayram, Mahmut Ülger, Gürol Emekdaş, Mustafa Fethi̇ Şahi̇n Jan 2011

Synthesis And In Vitro Antimycobacterial Activities Of Novel 6-Substituted-3(2h)-Pyridazinone-2-Acetyl-2-(Substituted/ Nonsubstituted Acetophenone) Hydrazone, Semra Utku, Mehtap Gökçe, Gönül Aslan, Gül Bayram, Mahmut Ülger, Gürol Emekdaş, Mustafa Fethi̇ Şahi̇n

Turkish Journal of Chemistry

The difficulty in managing tuberculosis includes the prolonged duration of the treatment, the emergence of drug resistance, and coinfection with HIV/AIDS. Tuberculosis control requires new drugs that act on novel drug targets to help in combating resistant forms of Mycobacterium tuberculosis and reduce the treatment duration. For this purpose, 6-substituted-3(2H)-pyridazinone-2-acetyl-2- (substituted/nonsubstituted acetophenone) hydrazone derivatives were synthesized and their structures were elucidated by elemental analyses, IR, and ^1H-NMR. The in vitro antimycobacterial activities of synthesized compounds 5a-l were determined by the agar proportion method against Mycobacterium tuberculosis H37Rv. Among the target compounds, 5b and 5f exhibited the best antimycobacterial activity, with …

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E)--2--Acetyl--4--(4--Methoxyphenyldiazenyl) Phenol: X--Ray And Dft--Calculated Structure, Serap Yazici, Çi̇ğdem Albayrak, İsmai̇l Erdem Gümrükçüoğlu, İsmet Şenel, Orhan Büyükgüngör Jan 2011

E)--2--Acetyl--4--(4--Methoxyphenyldiazenyl) Phenol: X--Ray And Dft--Calculated Structure, Serap Yazici, Çi̇ğdem Albayrak, İsmai̇l Erdem Gümrükçüoğlu, İsmet Şenel, Orhan Büyükgüngör

Turkish Journal of Chemistry

The crystal structure of the title compound, (E)-2-acetyl-4-(4-methoxyphenyldiazenyl) phenol, displays a trans configuration of the azo moiety as found for other azo (diazene) derivatives. The aromatic mean planes are nearly coplanar and the dihedral angle between the 2 aromatic rings is 3.04(8)°. The molecules, with strong intramolecular O--H...O hydrogen bonding, are linked by weak van der Waals interactions in the 3-dimensional network. The molecular geometry, determined using X-ray diffraction techniques, was also calculated with the density functional theory (DFT), employing the hybrid exchange-correlation functional B3LYP. Experimental and theoretical IR spectra of the compound were also calculated for comparison. The results …

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Electrocatalytic Oxidation Of Ethanol On Various Metal Ad-Layer Modified Au(111) Electrodes In Alkaline Solution, Zekerya Dursun, Şükri̇ye Ulubay Karabi̇beroğlu, Buket Gelmez, Aydan Başaran Jan 2011

Electrocatalytic Oxidation Of Ethanol On Various Metal Ad-Layer Modified Au(111) Electrodes In Alkaline Solution, Zekerya Dursun, Şükri̇ye Ulubay Karabi̇beroğlu, Buket Gelmez, Aydan Başaran

Turkish Journal of Chemistry

Ethanol oxidation was studied on single-crystal Au(111) electrodes that were modified by platinum, palladium, and cadmium metal ad-layers. The metal ad-layer modification was carried out by the underpotential deposition process, in which controlled amounts of Pt, Pd, and Cd were electrodeposited onto the substrate as submonolayer or monolayer coverage. The activity of the metal ad-layer modified Au(111) electrodes toward ethanol oxidation was studied in alkaline media, and recorded voltammograms were compared to those of bare single crystal Au(111) and polycrystalline gold and platinum disk electrodes. In terms of the desired shift in reduction potential and increased current density, the best …

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Tridentate Ligands Derived From L-Tert-Leucine For The Cu(Ii) Mediated Asymmetric Henry Reaction, Nesli̇han Korkmaz, Demet Astley, Stephen Thomas Astley Jan 2011

Tridentate Ligands Derived From L-Tert-Leucine For The Cu(Ii) Mediated Asymmetric Henry Reaction, Nesli̇han Korkmaz, Demet Astley, Stephen Thomas Astley

Turkish Journal of Chemistry

Chiral tridentate Schiff base ligands were prepared from L-tert-Leucine and used as catalysts in the asymmetric Henry reaction in the presence of Cu(II) ions. Moderate enantiomeric excesses (up to 66%) and yields (up to 76%) of the desired \beta-nitroalcohols were obtained.

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Zno Nanoflake Arrays Prepared Via Anodization And Their Performance In The Photodegradation Of Methyl Orange, Huey-Shya Goh, Rohana Adnan, Muhammad Akhyar Farrukh Jan 2011

Zno Nanoflake Arrays Prepared Via Anodization And Their Performance In The Photodegradation Of Methyl Orange, Huey-Shya Goh, Rohana Adnan, Muhammad Akhyar Farrukh

Turkish Journal of Chemistry

In the present work, anodization of zinc foil was investigated in a mixed electrolyte of ammonium sulfate and sodium hydroxide under the influence of different anodization times and concentrations of the electrolyte while the temperature and voltage were kept constant. The ZnO nanoflake arrays formed on Zn foil were characterized using a field emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscopy (EDX) analysis, and X-ray diffraction (XRD). The size of the nanoflakes increased as the anodization time increased, while increasing the concentration of (NH_4)_2SO_4 increased the dissolution of the nanoflakes. Upon stirring, the nanoflakes that formed were more uniform …

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One Pot Synthesis Of Pyridophenanthroline And Pyrrolophenanthroline Derivatives By Regioselective Reaction Between 1,7-Phenanthroline And Dialkyl Acetylenedicarboxylate: New Fused Heterocyclic Compounds, Malek Taher Maghsoodlou, Reza Heydari, Sayyed Mostafa Habibi Khorassani, Batool Tahami Pour, Ghasem Marandi, Farhad Maghfuri Jan 2011

One Pot Synthesis Of Pyridophenanthroline And Pyrrolophenanthroline Derivatives By Regioselective Reaction Between 1,7-Phenanthroline And Dialkyl Acetylenedicarboxylate: New Fused Heterocyclic Compounds, Malek Taher Maghsoodlou, Reza Heydari, Sayyed Mostafa Habibi Khorassani, Batool Tahami Pour, Ghasem Marandi, Farhad Maghfuri

Turkish Journal of Chemistry

1,7-Phenanthroline reacts with dialkyl acetylenedicarboxylate in a regioselective manner to give new macromolecules such as tetramethyl- 6aH-pyrido[1,2-i][1,7]phenanthroline-7,8,9,10-tetracarboxylate and trialkyl pyrrolo[1,2-i][1,7]phenanthroline-7,8,9-tricarboxylate derivatives.

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Synthesis And Antimicrobial Activity Of Methoxy Azachalcones And N-Alkyl Substituted Methoxy Azachalconium Bromides, Canan Albay, Nuran Kahri̇man, Nagi̇han Yilmaz İskender, Şengül Alpay Karaoğlu, Nuretti̇n Yayli Jan 2011

Synthesis And Antimicrobial Activity Of Methoxy Azachalcones And N-Alkyl Substituted Methoxy Azachalconium Bromides, Canan Albay, Nuran Kahri̇man, Nagi̇han Yilmaz İskender, Şengül Alpay Karaoğlu, Nuretti̇n Yayli

Turkish Journal of Chemistry

In this study, 18 new N-octyl, N-decyl, and N-dodecyl substituted o-, m-, and p-methoxy (E)-3- and 4-azachalcones, {4- or 3-[(1E)-3-(4-, 3-, or 2-methoxyphenyl)-3-oxoprop-1-en-1-yl]-1-alkyl (C_{8,10,12}) pyridinium bromides} (1a-6a, 1b-1b, and 1c-6c), and 4 new o-, and m-methoxy (E)-3- and 4-azachalcones (2, 3, 5, and 6) were synthesized and tested for antimicrobial activities against Escherichia coli, Yersinia pseudotuberculosis, Enterobacter aerogenes, Pseudomonas aeruginosa, Staphylococcus aureus, Enterococcus faecalis, Bacillus cereus, and Candida albicans. N-Alkyl substituted azachalconium bromides showed good antimicrobial activity against all tested microorganisms with minimal inhibitory concentration (MIC) values in the range of 0.42-58.7 \mu g/mL in most cases. Nonalkylated compounds 1-9 …

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Microwave Synthesis Of Some New Antimicrobial And Antiproliferative Butenamides And Pyrrolidine-2,5-Diones, Shadia Mahmoud Abdallah, Halima Aly Hefny Jan 2011

Microwave Synthesis Of Some New Antimicrobial And Antiproliferative Butenamides And Pyrrolidine-2,5-Diones, Shadia Mahmoud Abdallah, Halima Aly Hefny

Turkish Journal of Chemistry

Microwave irradiation, comparable to conventional thermal heating, proves to be a convenient method in assisting the synthesis of some butenamides, pyrrolidine-2,5-diones, and their benzenesulfonamido derivatives, which are known to have biological activities and wide medical and industrial applications. Both procedures were used to compare their efficiency in synthesizing butenamides and pyrrolidine-2,5-diones (2-25), which have important and wide applications, from condensation of \alpha,\beta-unsaturated anhydride (1) with the corresponding amines. Some of the products showed biological or cytotoxic (antiproliferative) activity.

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Qsar And Docking Studies Of Inhibition Activity Of 5,6-Dihydro 11-Alkylbenzo[\Alpha]Carbazole Derivatives Against Estrogen Receptor, Tuğba Taşkin, Fatma Sevi̇n Jan 2011

Qsar And Docking Studies Of Inhibition Activity Of 5,6-Dihydro 11-Alkylbenzo[\Alpha]Carbazole Derivatives Against Estrogen Receptor, Tuğba Taşkin, Fatma Sevi̇n

Turkish Journal of Chemistry

In the present study, QSAR and docking studies were applied to understand the nature of 5,6-dihydro 11-alkylbenzo[\alpha]carbazole derivatives and to investigate the interactions of homolog series with binding sites on selected a-chains of human estrogen receptors (hER). The best QSAR model was selected, having the correlation coefficient r = 0.924, squared correlation coefficient r^2 = 0.854, standard deviation s = 0.357, and cross-validated squared correlation coefficient Q^2 = 0.755. The QSAR model indicated that the descriptors E-HOMO and heat of formation play an important role in human estrogen receptor inhibitor activities. A docking study was also utilized to visualize the …

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Electrocatalytic Reactivity Of Pt Ad-Layer Modified Au(111) Single Crystal Electrodes On Reduction Of Oxygen, Zekerya Dursun, Şükri̇ye Ulubay Karabi̇beroğlu, Buket Gelmez, Fatma Ni̇l Ertaş Jan 2011

Electrocatalytic Reactivity Of Pt Ad-Layer Modified Au(111) Single Crystal Electrodes On Reduction Of Oxygen, Zekerya Dursun, Şükri̇ye Ulubay Karabi̇beroğlu, Buket Gelmez, Fatma Ni̇l Ertaş

Turkish Journal of Chemistry

Electrocatalytic reduction of oxygen at electrochemically deposited Pt ad-layer modified Au(111) electrodes was studied in an O_2-saturated NaOH (0.1 M) solution. The results were compared with those obtained by using a polycrystalline Pt electrode and another Pt-deposited electrode prepared by replacement with Cu on bare Au(111). Linear sweep voltammetry displayed a positive shift of the oxygen reduction potential by about 0.14 V compared to the bare Au(111) electrode. This shift was about 0.06 V compared to a Pt disk electrode. Tafel slopes gradually changed between 0.06 and 0.1 V/dec, from 0.075 to -0.10 V/dec, from lower to higher current density …

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In Silico Design Of Novel And Highly Selective Lysine-Specific Histone Demethylase Inhibitors, Ebru Demet Akdoğan, Burak Erman, Kemal Yelekçi̇ Jan 2011

In Silico Design Of Novel And Highly Selective Lysine-Specific Histone Demethylase Inhibitors, Ebru Demet Akdoğan, Burak Erman, Kemal Yelekçi̇

Turkish Journal of Chemistry

Histone lysine-specific demethylase (LSD1) is involved in a wide range of epigenetic processes and plays important roles in gene silencing, DNA transcription, DNA replication, DNA repair, and heterochromatin formation. Its active site shows a resemblance to those of 2 homologous enzymes, monamine oxidase A and B (MAO-A and MAO-B.) In the present work, starting from suitable scaffolds and generating thousands of structures from them, 10 potential inhibitors were obtained with structural and physicochemical properties selectively suitable for inhibiting LSD1. iLib Diverse software was used to generate the diverse structures and 3 docking tools, CDOCKER, GOLD, and AutoDock, were used to …

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