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Articles 1471 - 1500 of 2628
Full-Text Articles in Physical Sciences and Mathematics
Controlled Growth Of Two-Dimensional Copper Nanoplates In Graphite Gallery, Xiaobei Bin, Jiazang Chen, Hong Cao
Controlled Growth Of Two-Dimensional Copper Nanoplates In Graphite Gallery, Xiaobei Bin, Jiazang Chen, Hong Cao
Turkish Journal of Chemistry
Copper nanoplates embedded in a graphite gallery were obtained by in situ reduction of stage 1, stage 2, and stage 3 CuCl_2-graphite intercalation compound precursors. The characterization results indicated that the morphology of the copper species was that of a 2-dimensional or quasi-2-dimensional nanoplate in the graphite gallery. Interaction between the metallic nanoplates and graphene sheet was also detected. The hexagonal graphene network restricted the crystallization orientation of the copper nanoparticles, and, at the same time, the finite space between the graphene sheets prevented the increase of the thickness. This method would provide a convenient route to synthesize or assemble …
Assimilable Organic Carbon Generation From Algogenic Organic Matter In Drinking Water, Ji-Hoon Kim, Young-Ju Kim, Tahir Imran Qureshi
Assimilable Organic Carbon Generation From Algogenic Organic Matter In Drinking Water, Ji-Hoon Kim, Young-Ju Kim, Tahir Imran Qureshi
Turkish Journal of Chemistry
A study of assimilable organic carbon (AOC) derived from algogenic organic matter in different drinking water resources was conducted. Seasonal changes in the concentration of AOC at Kamafusa Dam were dependent on the algal cell numbers. Variations in AOC concentrations were found to be more reliant on the AOC-P17 component than the AOC-NOX component. The algal culture experiment showed that extracellular organic matter (EOM) released during the growth of Phormidium tenue in M-11 culture medium led to a significant increase in AOC concentration; however, no significant variations of AOC concentration were observed in CT culture medium containing high amounts of …
Synthesis, Crystal Structure, And Antioxidant Properties Of Novel 1,2,4-Triazol-5-Ones Containing 3,4-Dimethoxyphenyl And 3,4-Dihydroxyphenyl Moiety, Yasemi̇n Ünver, Sevgi̇ Meydanal, Kemal Sancak, Di̇lek Ünlüer, Reşat Ustabaş, Esra Düğdü
Synthesis, Crystal Structure, And Antioxidant Properties Of Novel 1,2,4-Triazol-5-Ones Containing 3,4-Dimethoxyphenyl And 3,4-Dihydroxyphenyl Moiety, Yasemi̇n Ünver, Sevgi̇ Meydanal, Kemal Sancak, Di̇lek Ünlüer, Reşat Ustabaş, Esra Düğdü
Turkish Journal of Chemistry
A series of new 4-(3,4-dimethoxyphenethyl)-5-akyl/aryl-2H- 1,2,4-triazol-3(4H)-ones (3a-g) was obtained by the reaction of ethyl 2-(ethoxy)(alkylidene/arylidene)hydrazinecarboxylate (1) and 2-(3,4-dimethoxyphen- yl)ethanamine (2). Compounds 4a-f and 5 were synthesized from the reaction of corresponding compounds 3a-f and 3g with BBr_3, respectively. With elemental analysis, IR, ^1H-NMR, and ^{13C-NMR spectral data, 14 newly synthesized compounds were characterized. The structure of compound 3a was inferred through IR, ^1H- and ^{13}C-NMR, elemental analysis, and X-ray spectral techniques. In addition, the newly synthesized chemicals were screened for their antioxidant properties. Among the chemicals tested, 4a, 4c, 4d, 4f, and 5 exhibited the highest degree of antioxidant activity.
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
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 …
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
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, …
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
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 …
E)--2--Acetyl--4--(4--Methoxyphenyldiazenyl) Phenol: X--Ray And Dft--Calculated Structure, Serap Yazici, Çi̇ğdem Albayrak, İsmai̇l Erdem Gümrükçüoğlu, İsmet Şenel, Orhan Büyükgüngör
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 …
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
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 …
Tridentate Ligands Derived From L-Tert-Leucine For The Cu(Ii) Mediated Asymmetric Henry Reaction, Nesli̇han Korkmaz, Demet Astley, Stephen Thomas Astley
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.
Zno Nanoflake Arrays Prepared Via Anodization And Their Performance In The Photodegradation Of Methyl Orange, Huey-Shya Goh, Rohana Adnan, Muhammad Akhyar Farrukh
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 …
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
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.
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
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 …
Synthesis And Characterization Of New Symmetrical 3,6-Bis[(25,26,27- Tripropoxy-28-(3-(4-Iodophenyl) Propoxy)-P-Tert-Butyl Calix[4]Arene Ethynyl]-9h- Fluoren-9-One By Sonogashira Coupling As A Novel Precursor For Synthesis Of Quinodimethane (Qdm), Karim Akbari Dilmaghani, Fazel Nasuhi Pur
Synthesis And Characterization Of New Symmetrical 3,6-Bis[(25,26,27- Tripropoxy-28-(3-(4-Iodophenyl) Propoxy)-P-Tert-Butyl Calix[4]Arene Ethynyl]-9h- Fluoren-9-One By Sonogashira Coupling As A Novel Precursor For Synthesis Of Quinodimethane (Qdm), Karim Akbari Dilmaghani, Fazel Nasuhi Pur
Turkish Journal of Chemistry
Novel symmetrical 3,6-bis[(25,26,27-tripropoxy-28-(3-(4-iodophenyl)propoxy)-p-tert-butyl calix[4]arene ethynyl]-9H-fluoren-9-one with a cone conformation was synthesized by palladium-catalyzed coupling of (25,26,27-tripropoxy- 28-(3-(4-iodophenyl)propoxy)-p-tert-butyl calix[4]arene and 3,6-diethynyl-9H-fluoren-9-one. Its structure was confirmed by FT-IR, ^1H-NMR, and ^{13}C-NMR spectroscopy, and elemental analysis and positive ion FAB mass spectrometry.
Microwave Synthesis Of Some New Antimicrobial And Antiproliferative Butenamides And Pyrrolidine-2,5-Diones, Shadia Mahmoud Abdallah, Halima Aly Hefny
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.
A Near-Infrared Fluorescent Sensor For H^+ In Aqueous Solution And Living Cells, Aibin Wu, Liping Duan
A Near-Infrared Fluorescent Sensor For H^+ In Aqueous Solution And Living Cells, Aibin Wu, Liping Duan
Turkish Journal of Chemistry
A heptamethine cyanine-based sensor (1) was designed and synthesized by incorporating heptamethine cyanine fluorophore and methylpiperazine. Sensor 1 exhibited good response to the change of pH levels, and a large Stokes shift (>100 nm) was obtained. Fluorescent image experiments in living cells further demonstrated its potential applications in biological systems.
Qsar And Docking Studies Of Inhibition Activity Of 5,6-Dihydro 11-Alkylbenzo[\Alpha]Carbazole Derivatives Against Estrogen Receptor, Tuğba Taşkin, Fatma Sevi̇n
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 …
Chemical Composition And Antimicrobial Activity Of The Essential Oils Of Geranium Columbinum L. And G. Lucidum L. (Geraniaceae), Niko Radulovic, Milan Dekic, Zorica Stojanovic-Radic, Radosav Palic
Chemical Composition And Antimicrobial Activity Of The Essential Oils Of Geranium Columbinum L. And G. Lucidum L. (Geraniaceae), Niko Radulovic, Milan Dekic, Zorica Stojanovic-Radic, Radosav Palic
Turkish Journal of Chemistry
The chemistry of Geranium columbinum and G. lucidum volatiles has been studied here for the first time. The essential oils were obtained by hydrodistillation, analyzed by GC and GC-MS, and screened for their in vitro antibacterial and antifungal activity in a microdilution assay. In total, 172 constituents were identified, accounting for 88.1%-96.7% of the detected GC peak areas. The essential oils consisted mainly of fatty acids and fatty acid-derived compounds (65.0%-86.3%). The major compounds of the essential oils were hexadecanoic acid, hexahydrofarnesyl acetone, and tetracosane. The antimicrobial assay showed a strong activity of the oil from aerial parts of G. …
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
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 …
In Silico Design Of Novel And Highly Selective Lysine-Specific Histone Demethylase Inhibitors, Ebru Demet Akdoğan, Burak Erman, Kemal Yelekçi̇
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 …
Synthesis Of New Substituted 2,2-Bis-(3,5-Di-T-Butyl-4-Hydroxybenzyl)Benzocycloalkanones, Bromopropiophenones, And Their Alcohol Analogs, Jabbar Khalafy, Mehdi Rimaz, Sara Taghinejhad, Mirzagha Babazadeh
Synthesis Of New Substituted 2,2-Bis-(3,5-Di-T-Butyl-4-Hydroxybenzyl)Benzocycloalkanones, Bromopropiophenones, And Their Alcohol Analogs, Jabbar Khalafy, Mehdi Rimaz, Sara Taghinejhad, Mirzagha Babazadeh
Turkish Journal of Chemistry
A new series of substituted 2,2-bis-(3,5-di-t-butyl-4-hydroxybenzyl) benzocycloalkanones, bromopropiophenones, and their alcohol analogs were synthesized. The corresponding alcohols may act as potential allosteric modulators of GABA_B receptors.
Enantioselective Henry Reaction Catalyzed By A Novel L-(+)-Aspartic Acid-Derived Schiff Base Ligand And Cu(Ii) Ion, Gamze Koz, Demet Astley, Stephen Thomas Astley
Enantioselective Henry Reaction Catalyzed By A Novel L-(+)-Aspartic Acid-Derived Schiff Base Ligand And Cu(Ii) Ion, Gamze Koz, Demet Astley, Stephen Thomas Astley
Turkish Journal of Chemistry
Mild and efficient enantioselective Henry reactions of nitromethane with various aldehydes were catalyzed by a novel L-(+)-aspartic acid-derived Schiff base ligand in the presence of Cu(II) ions, affording the corresponding adducts in high yields (up to 96%) and enantioselectivities (up to 92% ee).
Synthesis And Antimicrobial Activities Of Some Bridged Bis-Benzimidazole Derivatives, Hasan Küçükbay, Ülkü Yilmaz, Ni̇hat Şi̇reci̇, Ayşe Ni̇lay Güvenç
Synthesis And Antimicrobial Activities Of Some Bridged Bis-Benzimidazole Derivatives, Hasan Küçükbay, Ülkü Yilmaz, Ni̇hat Şi̇reci̇, Ayşe Ni̇lay Güvenç
Turkish Journal of Chemistry
Some bis-benzimidazoles derivatives bearing allyl, crotyl, cinammyl, furfuryl, and thenyl groups were synthesized and their in vitro antimicrobial activity determined against gram-positive and gram-negative bacteria, and fungi by disk-diffusion method. The structures of all new compounds were identified by ^1H-NMR, ^{13}C-NMR, and FT-IR spectroscopic techniques and elemental analysis. All the compounds synthesized in this work were examined for their in vitro antimicrobial activities against gram-positive (Staphylococcus aureus and Bacillus megaterium) and gram-negative bacteria (Klebsiella pneumoniae and Escherichia coli), and the yeasts like fungi (Candida globrata and Candida tropicalis). Compared to the reference substances, Cefozine and nystatin, most of the compounds …
Synthesis Of Novel Tetraoxime Derivative With Hydrazone Side Groups And Its Metal Complexes, İlknur Babahan, Hüseyi̇n Anil, Nursabah Sarikavakli
Synthesis Of Novel Tetraoxime Derivative With Hydrazone Side Groups And Its Metal Complexes, İlknur Babahan, Hüseyi̇n Anil, Nursabah Sarikavakli
Turkish Journal of Chemistry
In this study, the synthesis of a novel tetraoxime (LH_4) derivative containing hydrazone side groups, and its transition metal complexes with Ni(II), Cu(II), Co(II), and Zn(II) ions, were reported. The ligand was synthesized by reacting anti-glyoximehydrazine (GH_2) with terephthaldialdehyde. Polymeric complexes with Ni(II) and Co(II) and binuclear complexes with Cu(II) and Zn(II) of this tetraoxime were isolated. Structural assignments were supported by a combination of ^1H-NMR, ^{13}C-NMR, HMQC, FT-IR, UV-Vis, thermogravimetric analysis (TGA), molar conductances, elemental analyses, and magnetic susceptibility.
Solidified Floating Organic Drop Microextraction And Spectrophotometric Determination Of Vanadium In Water Samples, Shayessteh Dadfarnia, Ali Mohammad Haji Shabani, Akram Mirshamsi
Solidified Floating Organic Drop Microextraction And Spectrophotometric Determination Of Vanadium In Water Samples, Shayessteh Dadfarnia, Ali Mohammad Haji Shabani, Akram Mirshamsi
Turkish Journal of Chemistry
Solidified floating organic drop microextraction (SFODME) was used as a sample preparation method prior to spectrophotometric determination of trace amounts of vanadium in water samples. 8-Hydroxyquinoline (oxine) was used as the chelating agent. The main parameters affecting the performance of SFODME, such as pH, concentration of oxine, extraction time, sample and organic phase volume, extraction temperature, and the nature of the organic solvent, were optimized. Under the optimized conditions, an enhancement factor of 38, detection limit of 0.97 \mu g L^{-1}, and good relative standard deviation of \pm 3.9% at 10 \mu g L^{-1} were obtained. The method was successfully …
Antioxidant Phenolics From Lobaria Pulmonaria (L.) Hoffm. And Usnea Longissima Ach. Lichen Species, Fadi̇me Atalay, Mesut Bünyami̇ Halici, Ahmet Mavi̇, Ahmet Çakir, Fehmi̇ Odabaşoğlu, Cavi̇t Kazaz, Ali̇ Aslan, Ömer İrfan Küfrevi̇oğlu
Antioxidant Phenolics From Lobaria Pulmonaria (L.) Hoffm. And Usnea Longissima Ach. Lichen Species, Fadi̇me Atalay, Mesut Bünyami̇ Halici, Ahmet Mavi̇, Ahmet Çakir, Fehmi̇ Odabaşoğlu, Cavi̇t Kazaz, Ali̇ Aslan, Ömer İrfan Küfrevi̇oğlu
Turkish Journal of Chemistry
In this study, 1 steroidal and 8 phenolic compounds from Lobaria pulmonaria (L.) Hoffm. and Usnea longissima Ach. were isolated and their chemical structures were characterized by ^1H-NMR, ^{13}C-NMR, DEPT, ^1H-^1H COSY, HMQC, HMBC, IR, UV, and MS spectroscopic methods as stictic acid, isidiophorin, rhizonaldehyde, rhizonyl alcohol, pulmonarianin, vesuvianic acid, ergosterol peroxide, usnic acid, and diffractaic acid. Among these compounds, pulmonarianin, isolated from L. pulmonaria, was characterized for the first time as a natural compound. In addition to isolation and characterization, the lipid peroxidation inhibition and DPPH radical scavenging activities of the isolated compounds were investigated. Among these compounds, isidiophorin, …
In Situ Catalytic Activities Of 1,3-Dialkyltetrahydropyrimidinium Salts/[Rucl_2(P-Cymene)]_2 System For Transfer Hydrogenation Reactions, Emi̇ne Özge Özcan, Deni̇z Mercan, Nevi̇n Gürbüz, Engi̇n Çeti̇nkaya, Beki̇r Çeti̇nkaya, İsmai̇l Özdemi̇r
In Situ Catalytic Activities Of 1,3-Dialkyltetrahydropyrimidinium Salts/[Rucl_2(P-Cymene)]_2 System For Transfer Hydrogenation Reactions, Emi̇ne Özge Özcan, Deni̇z Mercan, Nevi̇n Gürbüz, Engi̇n Çeti̇nkaya, Beki̇r Çeti̇nkaya, İsmai̇l Özdemi̇r
Turkish Journal of Chemistry
Hydrogen-transfer reduction processes are attracting increasing interest from synthetic chemists in view of their operational simplicity. In the present study novel ruthenium carbene complexes were generated in situ and tested for their transfer hydrogenation reactions. The in situ prepared 3 component 1,3-dialkyltetrahydropyrimidinium salts (LHX)/[RuCl_2(p-cymene)]_2 and KOH catalyzed quantitatively the transfer hydrogenation of ketones under mild reaction conditions in 2-propanol.
Electrocatalytic Oxidation Of Methanol At Pd And Pt Ad-Layer Modified Au(111) Electrodes In Alkaline Solution, Süleyman Koçak, Zekerya Dursun, Fatma Ni̇l Ertaş
Electrocatalytic Oxidation Of Methanol At Pd And Pt Ad-Layer Modified Au(111) Electrodes In Alkaline Solution, Süleyman Koçak, Zekerya Dursun, Fatma Ni̇l Ertaş
Turkish Journal of Chemistry
The electrochemical oxidation of methanol was investigated by using various ad-layer modified Au(111) electrodes in alkaline media in comparison to Au(111), polycrystalline Pd, and polycrystalline Pt electrodes. Catalytic activity of gold toward methanol oxidation has tended to increase in more alkaline media, as reflected in the oxidation peak in the concentration range of NaOH (0.1-3.0 M) studied here. The oxidation peak potential of methanol shifted to more negative potentials, indicating a pH-dependent surface reaction. Among the electrodes studied, single-crystal gold electrode surfaces modified with Pd and Pt ad-layers displayed the highest catalytic activity for methanol oxidation. Additional shifts of about …
Preparation And Characterization Of A Series Of Thiourea Derivatives As Phase Change Materials For Thermal Energy Storage, Cemi̇l Alkan, Yusuf Tek, Derya Kahraman
Preparation And Characterization Of A Series Of Thiourea Derivatives As Phase Change Materials For Thermal Energy Storage, Cemi̇l Alkan, Yusuf Tek, Derya Kahraman
Turkish Journal of Chemistry
A series of solid-liquid phase change materials, thiourea derivatives, were prepared via condensation of thiourea with the respective carboxyl chlorides (lauroyl chloride, myristoyl chloride, and palmitoyl chloride) and were then characterized by using FT-IR, ^1H-NMR, differential scanning calorimetry (DSC), and thermogravimetric (TG) analysis. The thiourea derivatives (1,3-didodecanoyl thiourea, 1,3-ditetradecanoyl thiourea, and 1,3-dihexadecanoyl thiourea) were structurally symmetric and had long alkyl groups to crystallize. Thermal analysis by DSC and spectroscopic investigation by FT-IR spectroscopy were performed on the samples before and after thermal cycling tests to determine thermal reliability. The maximum latent heats of melting and freezing of the thiourea derivatives …
A New And Simple Procedure For The Polarographic Speciation And Determination Of Trace Inorganic As(Iii) And As(V) Species, Ülkü Ünal, Güler Somer
A New And Simple Procedure For The Polarographic Speciation And Determination Of Trace Inorganic As(Iii) And As(V) Species, Ülkü Ünal, Güler Somer
Turkish Journal of Chemistry
A new and simple differential pulse polarographic method was developed for the trace determination of As(III) and As(V) species in the same sample. Among several electrolytes, 0.1 M HCl was found to be the most suitable. As(III) had 3 peaks in this medium, and the peak at --0.82 V was chosen because of its peak shape and response to standard additions. In this medium, the limit of detection for As(III) was found to be 1.5 \times 10^{-7} M. Since As(V) is not electroactive, it had to be reduced first into As(III). For this purpose, KI in an acidic and hot …
Remediation Of Various Naturally Oxygenated Volatile Organic Compounds (O-Vocs) By Mn- And Cr-Supported \Gamma -Al_2o_3 Nanocatalysts, Dariush Salari, Aligholi Niaei, Seyed Ali Hosseini, Reza Leshzadeh, Hosein Afshary
Remediation Of Various Naturally Oxygenated Volatile Organic Compounds (O-Vocs) By Mn- And Cr-Supported \Gamma -Al_2o_3 Nanocatalysts, Dariush Salari, Aligholi Niaei, Seyed Ali Hosseini, Reza Leshzadeh, Hosein Afshary
Turkish Journal of Chemistry
The catalytic combustions of different naturally oxygenated volatile organic compounds (ethyl acetate, isopropanol, methyl ethyl ketone (MEK), and benzyl alcohol) alone and in binary mixtures were investigated over pure \gamma -Al_2O_3, Mn/\gamma -Al_2O_3, and Cr/\gamma -Al_2O_3. The catalysts were prepared by the wet impregnation method and were characterized using XRD, ICP-AES, SEM, and BET. Mn/\gamma -Al_2O_3 showed higher activity than others in combustion of the O-VOCs, whereas complete conversion of isopropanol (the most reactive O-VOC) occurred at 350 °C and 400 °C on Mn/\gamma -Al_2O_3 and Cr/\gamma -Al_2O_3, respectively. The following order was found for reactivity of organic compounds in …