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Articles 5251 - 5280 of 5872
Full-Text Articles in Physical Sciences and Mathematics
Synthesis Of A Ruthenium Complex Bound To A Polyimide Matrix: Investigating The Catalytic Properties In A Hydrosilylation Reaction, Turgay Seçki̇n, Süleyman Köytepe, İsmai̇l Özdemi̇r, Beki̇r Çeti̇nkaya
Synthesis Of A Ruthenium Complex Bound To A Polyimide Matrix: Investigating The Catalytic Properties In A Hydrosilylation Reaction, Turgay Seçki̇n, Süleyman Köytepe, İsmai̇l Özdemi̇r, Beki̇r Çeti̇nkaya
Turkish Journal of Chemistry
3,6-Bis(dimethylamino)acridine(hexamethylbenzene)dichlororuthenium(II) was used as a tricyclic heteroatomic monomer to prepare polyimides from the corresponding dianhyrides by solution condensation. The ruthenium complex monomer was synthesized starting from [RuCl_2(HMB)]_2 and 3-6-bis(dimethylamino)acridine. The polymers had inherent viscosities of 1.77 to 2.11 and were soluble in most polar solvents. The glass transition temperatures were in the range of 204 to 298 °C and the 10% weight loss in the range of 506-626 °C, depending upon the structure of the dianhyride monomer. The catalytic activity of the polyimides tested in a hydrosilylation reaction of acetophenone was up to 90%. Leaching of ruthenium into the reaction …
Structure Of 1-(Thiophen-2-Ylmethyl)-2-(Thiophen-2-Yl)-1h-Benzimidazole, Necmi̇ Dege, Memet Şekerci̇, Süleyman Servi̇, Muharrem Di̇nçer, Ünzi̇le Demi̇rbaş
Structure Of 1-(Thiophen-2-Ylmethyl)-2-(Thiophen-2-Yl)-1h-Benzimidazole, Necmi̇ Dege, Memet Şekerci̇, Süleyman Servi̇, Muharrem Di̇nçer, Ünzi̇le Demi̇rbaş
Turkish Journal of Chemistry
The title compound, C_{16}H_{12}N_2S_2, crystallizes in the monoclinic space group P2_1/n with Z = 4, a = 8.950 (5) Å, b = 9.141 (5) Å, c = 17.429 (5) Å and \beta = 93.638 (5)°. The benzimidazole ring is essentially planar. The crystal structure is stabilized by intermolecular C---H ... N and C---H ... \pi contacts.
Studies On 2-Ethyl-3-Carbmethoxy-4-Aryl-5-Oxo-1,4,5,6,7,8-Hexahydroquinoline Derivatives And Calcium Modulatory Activities, Ci̇hat Şafak, Elvan Doğan, Kevser Erol
Studies On 2-Ethyl-3-Carbmethoxy-4-Aryl-5-Oxo-1,4,5,6,7,8-Hexahydroquinoline Derivatives And Calcium Modulatory Activities, Ci̇hat Şafak, Elvan Doğan, Kevser Erol
Turkish Journal of Chemistry
Twelve new compounds having a 2-ethyl-3-carbmethoxy-4-aryl-5-oxo-1,4,5,6,7,8-hexahydroquinoline structure were synthesized, characterized and screened for their calcium modulatory activities. The calcium antagonistic activities of the compounds were investigated by tests performed on isolated rat ileum and lamb carotid artery. Compounds 1, 4, 8 and 9 showed considerable activity.
Heterocyclic Synthesis Using Nitrilimines: Part 5. Synthesis Of Some Novel Spiro Heterocycles, Hany M. Dalloul, Peter H. Boyle
Heterocyclic Synthesis Using Nitrilimines: Part 5. Synthesis Of Some Novel Spiro Heterocycles, Hany M. Dalloul, Peter H. Boyle
Turkish Journal of Chemistry
A new class of spiro-triazoles (4a-m) were synthesized from the reaction of corresponding nitrilimines 2 with substituted heterocyclic benzoylhydrazones 3 in good yields. The spectral data of the new synthesized compounds are in full agreement with their molecular structure.
Synthesis Of New 3-Pyrrolin-2-One Derivatives, Nezi̇re Saygili, Ayşegül Altunbaş, Akgül Yeşi̇lada
Synthesis Of New 3-Pyrrolin-2-One Derivatives, Nezi̇re Saygili, Ayşegül Altunbaş, Akgül Yeşi̇lada
Turkish Journal of Chemistry
Six new 3-pyrrolin-2-one derivatives were synthesized via the condensation reaction of amino acid esters (2a-f) with 2,5-dimethoxy-2,5-dihydrofurane (1) in acidic medium. This simple one-pot reaction furnished the corresponding pyrrolinones (3a-f) in acceptable yields.
Construction Of A Homonaphthazarin Skeleton And Synthesis Of Hydroquinone-Annelated Cycloheptatriene Derivatives, Emi̇n Şengül, Abdullah Menzek, Meti̇n Balci
Construction Of A Homonaphthazarin Skeleton And Synthesis Of Hydroquinone-Annelated Cycloheptatriene Derivatives, Emi̇n Şengül, Abdullah Menzek, Meti̇n Balci
Turkish Journal of Chemistry
1,4-Dihydroxy-7,8-dihydro-5H-benzo[a]cycloheptene-5,9(6H)- dione (7) was synthesised from hydroquinone and glutaric acid chloride via an acylation reaction. The reaction of dione (7) with bromine followed by treatment with NEt_3 gave homonaphthazarin 8 as well as the brominated derivatives 9 and 10. Reduction of 1,4-dimethoxy-7,8-dihydro-5H-benzo[a]cycloheptene-5,9(6H)-dione (16) with LiAlH_4 gave 2 isomeric alcohols, 17 and 18. Reaction of these alcohols with SOCl_2 followed by HCl elimination with NEt_3 afforded dimethoxybenzocycloheptatriene 19 as the sole product. For the synthesis of the isomeric cycloheptatriene 20, the double bond in 19 was isomerised with KOt-Bu.
Synthesis Of N-Alkylnaphthalenes Via Semicarbazones, Gülay Zengi̇n, John W. Huffman
Synthesis Of N-Alkylnaphthalenes Via Semicarbazones, Gülay Zengi̇n, John W. Huffman
Turkish Journal of Chemistry
A number of 1-n-alkylnaphthalenes were prepared via the respective semicarbazones. The semicarbazones were reduced by modified Wolff-Kishner reductions to give 1-n-alkylnaphthalenes in excellent yields as manageable yellow or orange viscous oils. The semicarbazones were prepared from ketones, which are the addition products of Grignard reagents to nitriles. This study offers an excellent preparative method for the synthesis of 1-n-alkylnaphthalenes from semicarbazones, via a 3-step procedure.
Formation Of Yttrium(Iii) Complexes With Salicylic Acid Derivatives In Aqueous Solution, Rahmi̇ye Aydin, Ulvi̇ye Özer
Formation Of Yttrium(Iii) Complexes With Salicylic Acid Derivatives In Aqueous Solution, Rahmi̇ye Aydin, Ulvi̇ye Özer
Turkish Journal of Chemistry
Complexes of yttrium(III) formed with 5-sulphosalicylic acid, 5-SSA (H_3L), and 5-nitrosalicylic acid, 5-NSA (H_2L), were investigated in 0.1 mol.dm^{-3} sodium perchlorate ionic medium at 25.0 \pm 0.1 °C potentiometrically for various molar ratios of Y(III) to these salicylic acid, SA (H_2L), derivatives. Y(III) forms YL and YL_2^{3-} type complexes with 5-SSA that have rather high stabilities (log \beta _1 = 7.91 \pm 0.01 and log \beta _2 = 14.56 \pm 0.06). In the Y(III):5-NSA system, YL^+ and YL_2^- type complexes appear with high stabilities (log \beta _1 = 7.39 \pm 0.02 and log \beta _2 = 13.50 \pm 0.07). Y(III):5-SSA …
Heterogeneous Electron Transfer Rate Constants Of Viologen Monocations At A Platinum Disk Electrode, Naheed Kaukab Bhatti, M. Sadiq Subhani, Ather Yaseen Khan, Rumana Qureshi, Abdur Rahman
Heterogeneous Electron Transfer Rate Constants Of Viologen Monocations At A Platinum Disk Electrode, Naheed Kaukab Bhatti, M. Sadiq Subhani, Ather Yaseen Khan, Rumana Qureshi, Abdur Rahman
Turkish Journal of Chemistry
Experimental values of rate constants for the heterogeneous transfer of electrons to methyl viologen, diquat viologen, benzyl viologen and n-butyl viologen monocations were determined. The process was studied at the surface of a platinum disk in mixtures of water with different aprotic solvents at different temperatures. Theoretical rate constants were evaluated using Marcus' equation, which also contains barrier crossing probability and nuclear frequency. A comparison was made between the theoretical and experimental values of rate constants.
Optimization Of The Nonaqueous Capillary Electrophoresis Separation Of Metal Ions Using Mixture Design And Response Surface Methods, Cevdet Demi̇r, Yasi̇n Yücel
Optimization Of The Nonaqueous Capillary Electrophoresis Separation Of Metal Ions Using Mixture Design And Response Surface Methods, Cevdet Demi̇r, Yasi̇n Yücel
Turkish Journal of Chemistry
Mixture experimental design was used to enhance the separation selectivity of metal ions in nonaqueous capillary electrophoresis. The separation of cations (Ag, Fe, Cr, Mn, Cd, Co, Pb, Ni, Zn and Cu) was achieved using imidazole as UV co-ion for indirect detection. Acetic acid was chosen as an electrolyte because its cathodic electroosmotic flow permits faster separation. The composition of organic solvents is important to achieve the best separation of all metal ions. Simplex lattice design and response surface methods have proved to be an effective tool to optimize the composition of organic solvents in nonaqueous capillary electrophoresis. Full and …
Organotin (Iv) Derivatives Of 1-Ethyl-1,4-Dihydro-7-Methyl-4-Oxo- 1,8-Naphthyridine-3-Carboxylic Acid (Nalidixic Acid): Synthesis, Structural Elucidation And Biological Activities, Sajjad Ahmed, Moazzam Hussain Bhatti, Saqib Ali, Fiaz Ahmed
Organotin (Iv) Derivatives Of 1-Ethyl-1,4-Dihydro-7-Methyl-4-Oxo- 1,8-Naphthyridine-3-Carboxylic Acid (Nalidixic Acid): Synthesis, Structural Elucidation And Biological Activities, Sajjad Ahmed, Moazzam Hussain Bhatti, Saqib Ali, Fiaz Ahmed
Turkish Journal of Chemistry
Organotin carboxylates of the general formulae R_2SnL_2 and R_3SnL, where R = CH_3, n-C_4H_9, C_6H_5, CH_2C_6H_5 and L = 1-ethyl-1,4-dihydro-7-methyl-4-oxo-1,8-naphthyridine-3-carboxylic acid (nalidixic acid), have been prepared. These compounds were characterized by FT-IR, mass and multinuclear NMR (^1H, ^{13}C and ^{119}Sn) spectroscopy. The geometry around the tin atom is compared both in solution and in solid state. These compounds were also screened for their antifungal and antibacterial activities.
Surface Modification Of Glass Beads With An Aminosilane Monolayer, Gülşi̇n Arslan, Mustafa Özmen, Beni̇z Gündüz, Xunli Zhang, Mustafa Ersöz
Surface Modification Of Glass Beads With An Aminosilane Monolayer, Gülşi̇n Arslan, Mustafa Özmen, Beni̇z Gündüz, Xunli Zhang, Mustafa Ersöz
Turkish Journal of Chemistry
Surface modification of glass beads with a self-assembled monolayer of (3-Aminopropyl)-triethoxysilane (APTES) was investigated. Characterisation of the self-assembled monolayer was confirmed by a reaction between amine terminal groups and thionylchloride of Rhodamine-B dye using fluorescence microscopy. Quantitative 3-dimensional profiling was obtained for all modification processes by converting microscopic images to numerical values. The reaction steps were also analysed using infrared spectroscopy (FTIR).
Surface Properties And Catalytic Performance Of Pt/Prsrcoo_4 Catalysts For No Reduction By Co, Hua Zhong, Xirui Zeng
Surface Properties And Catalytic Performance Of Pt/Prsrcoo_4 Catalysts For No Reduction By Co, Hua Zhong, Xirui Zeng
Turkish Journal of Chemistry
Perovskite-type Pr_{2-x}Sr_xCoO_{4\pm \lambda} mixed oxides were prepared by different calcination temperatures and were investigated by XRD, BET, TPD, TPR and XPS methods. These catalysts possess high catalytic activities towards the NO reduction by CO, and the activity of the PrSrCoO_4 catalyst prepared by calcining at 750 °C is the best among these samples. This is explained in terms of its greater oxygen vacancies and larger BET surface areas. The influence of modification by a suitable amount of Pt-doping on the surface properties and catalytic activity for NO reduction by CO was studied. The results show that the Pt-modified PrSrCoO_4 catalysts …
Synthesis And Antifungal Properties Of Some Benzimidazole Derivatives, Gülgün Ayhan Kilcigi̇l, Nurten Altanlar
Synthesis And Antifungal Properties Of Some Benzimidazole Derivatives, Gülgün Ayhan Kilcigi̇l, Nurten Altanlar
Turkish Journal of Chemistry
Some benzimidazole derivatives were synthesized and their in vitro antifungal activities were tested against Candida albicans, Candida glabrata and Candida krusei. Compounds 6 and 9 possessed activity comparable to fluconazole against C. albicans with a minimum inhibitory concentration of 12.5 \mu g/mL.
Sesquiterpene Lactones From Centaurea Helenioides Boiss, Nuretti̇n Yayli, Cemaletti̇n Baltaci, Yaşar Gök, Ebru Aydin, Osman Üçüncü
Sesquiterpene Lactones From Centaurea Helenioides Boiss, Nuretti̇n Yayli, Cemaletti̇n Baltaci, Yaşar Gök, Ebru Aydin, Osman Üçüncü
Turkish Journal of Chemistry
Grosheimin (1) and cynaropicrin (3) sesquiterpenes were isolated from the flowers of Centaurea helenioides Boiss., an endemic plant of Turkey. The products are known as they occur in another species, but they were isolated and identified for the first time from C. helenioides Boiss. In order to correlate spectral data of grosheimin, its acetyl derivative, 8\alpha -acetyl grosheimin (2) was also prepared. Their structures were deduced by FT-IR, UV, 1D and 2D NMR, LC MS/MS, GC-mass spectra (EI), optical rotation, and chemical methods.
Synthesis Of Methylthionaphthalene Derivatives, Ayşegül Öncü, Nurgün Sakarya Büyükkidan, Bülent Büyükkidan, Osman Çakmak
Synthesis Of Methylthionaphthalene Derivatives, Ayşegül Öncü, Nurgün Sakarya Büyükkidan, Bülent Büyükkidan, Osman Çakmak
Turkish Journal of Chemistry
No abstract provided.
Gc-Ms Analysis And Antibacterial Activity Of Cultivated Satureja Cuneifolia Ten. Essential Oil, Yüksel Kan, Uçkun Sai̇t Uçan, Murat Kartal, M. Levent Altun, Si̇nem Aslan, Esi̇n Sayar, Ti̇murhan Ceyhan
Gc-Ms Analysis And Antibacterial Activity Of Cultivated Satureja Cuneifolia Ten. Essential Oil, Yüksel Kan, Uçkun Sai̇t Uçan, Murat Kartal, M. Levent Altun, Si̇nem Aslan, Esi̇n Sayar, Ti̇murhan Ceyhan
Turkish Journal of Chemistry
The composition of the essential oil of Satureja cuneifolia Ten. cultivated in Konya, Turkey, was investigated by capillary GC-MS. The compounds were characterized by comparison with library searches. Six main compounds were identified. Carvacrol was the dominant component, comprising 59.28% of the essential oil. The oil also contained 15.72% thymol, 9.69% p-cymene, 4.16% \gamma -terpinene, 1.70% linalool and 1.25% borneol. The antibacterial activity of the essential oil of S. cuneifolia and its components was determined by a semiquantative disc-diffusion method, and the minimum inhibitory concentration (MIC) was determined based on a micro-well dilution method against strains of Pseudomonas aeruginosa, Bacillus …
Investigation Of The Cation Complexation By Macrocyclic Ethers Using ^{13}C Nmr Spin--Lattice Dipolar Relaxation Time Measurements, Çakil Erk, Matthias Heydenreich, Erich Kleinpeter
Investigation Of The Cation Complexation By Macrocyclic Ethers Using ^{13}C Nmr Spin--Lattice Dipolar Relaxation Time Measurements, Çakil Erk, Matthias Heydenreich, Erich Kleinpeter
Turkish Journal of Chemistry
The binding constants (K_a) of [18]crown-6 ether with Na^+ , K^+, and Ba^{2+} thiocyanates were determined by ^{13}C{^1H} NMR spin--lattice dipolar relaxation time measurements. The observed relaxation times (T_{obs}) for ^{13}C nuclei are dependent upon the relaxation times of the complexed (T_{1a}) and free crown ether (T_{1f}), and were measured in [D4]methanol using inversion--recovery measurements in the extreme narrowing limit (75 MHz). The observed ^{13}C relaxation times of the metal complexes were found to be smaller than those of the cation-free macrocyclic ether due to reduced internal flexibility of the macrocycles in the complexes. The relationship 1/T_{obs} = P_a/T_{1a} + …
Cumene Cracking On Modified Mesoporous Material Type Mcm-41, Ahmed Belhakem, Abdelkader Bengueddach
Cumene Cracking On Modified Mesoporous Material Type Mcm-41, Ahmed Belhakem, Abdelkader Bengueddach
Turkish Journal of Chemistry
The effect of ionic exchange degree of H(X)-AlMCM-41 materials, the method of its exchange and its grain form were investigated for mesoporous catalytic activity in the cumene cracking reaction. Benzene, propylene and xylene derivatives are the main products of this reaction. Olefins like butene and pentene appeared as the products of secondary reactions. No saturated hydrocarbons, which are typical products of secondary reactions obtained with HNaY zeolites, were formed, except for traces of butane. Generally the exchanged H(X)-AlMCM-41 materials by the substitution of Na^+ by NH_4^+ are more active than those exchanged directly with acid solution (substitution of Na^+ by …
Online Viscosity Measurement Of Complex Solutions Using Ultrasound Doppler Velocimetry, Volkan Köseli̇, Şeri̇fe Zeybek, Yusuf Uludağ
Online Viscosity Measurement Of Complex Solutions Using Ultrasound Doppler Velocimetry, Volkan Köseli̇, Şeri̇fe Zeybek, Yusuf Uludağ
Turkish Journal of Chemistry
A new method to measure the viscosity of non-Newtonian fluids over a wide range of shear rates in a short period of time is presented. The technique is based on the measurement of the velocity profile in a pipe flow using ultrasound Doppler velocimetry (UDV), which is a non-invasive method, and simultaneously determining the pressure drop. The velocity profile is used to obtain shear rate distribution, while the pressure drop is used to calculate the shear stress distribution. By taking the ratio of these quantities at a radial position, local viscosity can be obtained within the shear rate range in …
Secondary Metabolites From Euphorbia Helioscopia And Their Vasodepressor Activity, Asli Barla, Hüsni̇ye Bi̇rman, Şükran Kültür, Sevi̇l Öksüz
Secondary Metabolites From Euphorbia Helioscopia And Their Vasodepressor Activity, Asli Barla, Hüsni̇ye Bi̇rman, Şükran Kültür, Sevi̇l Öksüz
Turkish Journal of Chemistry
From the aerial parts of Euphorbia helioscopia L. (Euphorbiaceae), a jatrophane diterpene ester, 5,11-jatrophadiene-3-benzoyloxy-7,9,14-tri-acetyloxy-15-ol and 2 lupane derivatives, lup-20(29)-ene-3-acetate and lup-20(29)-ene-3-palmitate, together with common triterpenoids of Euphorbiaceae, 24-methylene cycloartanol, 24-methylenecycloart-3-one, cycloartanol, and stigmast-4-ene-3-one were isolated. The last compounds, lup-20(29)-ene-3-acetate, 24-methylene cycloartanol, 24-methylenecycloart-3-one, cycloartanol, and stigmast-4-ene-3-one, were isolated for the first time from E. helioscopia}. The fractions and the isolates were tested for their vasodepressor effects using Wistar Albino rats, and 5,11-jatrophadiene-3-benzoyloxy-7,9,14-tri-acetyloxy- 15-ol, lup-20(29)-ene-3-acetate, and stigmast-4-ene-3-one were found to possess relevant activity. The structures of all of the compounds were identified with high field spectroscopic methods. The detailed spectroscopic data of …
A Novel Approach To The Hydrothermal Synthesis Of Anatase Titania Nanoparticles And The Photocatalytic Degradation Of Rhodamine B, Murat Akarsu, Meltem Asi̇ltürk, Funda Sayilkan, Nadi̇r Ki̇raz, Ertuğrul Arpaç, Hi̇kmet Sayilkan
A Novel Approach To The Hydrothermal Synthesis Of Anatase Titania Nanoparticles And The Photocatalytic Degradation Of Rhodamine B, Murat Akarsu, Meltem Asi̇ltürk, Funda Sayilkan, Nadi̇r Ki̇raz, Ertuğrul Arpaç, Hi̇kmet Sayilkan
Turkish Journal of Chemistry
A novel approach was developed for the synthesis of high-dispersed anatase nano-TiO_2 by a hydrothermal process without solvent at 200 °C in 1 h. It was characterized using XRD, TEM, BET and elemental analysis. Nanoparticle-TiO_2 was used as a photocatalyst by considering complete degradation of Rhodamine B (RB) dye. The photocatalytic reaction parameters such as photocatalyst amount, irradiation time and dye concentration were optimized and it was found that 0.125 wt% catalyst in 30 mg/L of RB aqueous solution is adequate for full degradation of RB in 50 min with 770 W/m^2 irradiation power. Photocatalytic activity of the nanoparticle-TiO_2 was …
Synthesis And Spectroscopic Characterization Of Biologically Active Triarylantimony(V) Carboxylates Containing Germanium, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Khadija Shahid, Farnaz Malik
Synthesis And Spectroscopic Characterization Of Biologically Active Triarylantimony(V) Carboxylates Containing Germanium, Muhammad Kaleem Khosa, Muhammad Mazhar, Saqib Ali, Khadija Shahid, Farnaz Malik
Turkish Journal of Chemistry
A new series of bimetallic (Ge and Sb) compounds (1-7) was synthesized and characterized by elemental analyses, FT-IR, multinuclear NMR (^1H, ^{13}C) spectroscopy and mass spectrometry. These techniques not only confirmed the formation of the compounds, but also revealed their trigonal bipyramidal geometry around antimony(V). Selected compounds were screened against different pathogens and showed promising antibacterial and antifungal activities.
Synthesis And Antimicrobial Activity Of Some New 3-Substituted Benzyl-5-(4-Chloro-2-Piperidin-1yl-Thiazole-5-Yl-Methylene)-Thiazolidine-2,4-Dione Derivatives, Meltem Ceylan Ünlüsoy, Oya Bozdağ Dündar, Nurten Altanlar, Rahmi̇ye Ertan
Synthesis And Antimicrobial Activity Of Some New 3-Substituted Benzyl-5-(4-Chloro-2-Piperidin-1yl-Thiazole-5-Yl-Methylene)-Thiazolidine-2,4-Dione Derivatives, Meltem Ceylan Ünlüsoy, Oya Bozdağ Dündar, Nurten Altanlar, Rahmi̇ye Ertan
Turkish Journal of Chemistry
A new series of thiazolyl thiazolidine-2,4-dione (Va-f) were synthesized and their structures were elucidated by IR, ^1H-NMR, mass spectra and elementary analysis. The synthesized compounds were tested for their antimicrobial activities against Candida albicans, Staphylococcus aureus, Bacillus subtilis and Escherichia coli. Compounds Va-b, Vd-f showed high activity against Escherichia coli comparable to ampicillin.
Metal Complexes Of Schiff Bases: Preparation, Characterization, And Biological Activity, Gehad Genidy Mohamed, Mohamed Mohamed Omar, Ahmed Mohamed Hindy
Metal Complexes Of Schiff Bases: Preparation, Characterization, And Biological Activity, Gehad Genidy Mohamed, Mohamed Mohamed Omar, Ahmed Mohamed Hindy
Turkish Journal of Chemistry
Metal complexes of Schiff bases derived from 2-furancarboxaldehyde and o-phenylenediamine (L^1), and 2-thiophenecarboxaldehyde and 2-aminothiophenol (HL^2) are reported and characterized based on elemental analyses, IR ^1H NMR, solid reflectance, magnetic moment, molar conductance, and thermal analysis (TGA). The ligand dissociation, as well as the metal-ligand stability constants were calculated, pH-metrically, at 25 °C and ionic strength \mu = 0.1 (1 M NaCl). The complexes are found to have the formulae [M(L^1)(H_2O)_2](Cl)_n \cdot yH_2O (where M = Fe(III), Ni(II), Cu(II); n = 2-3, y = 2-4); [M(L^1)](X)_2 \cdot yH_2O (where M = Co(II), Zn(II), UO_2(II), X = Cl, AcO or NO_3, …
Secondary Metabolites From Phlomis Syriaca And Their Antioxidant Activities, Ü. Şebnem Harput, İhsan Çaliş, İclal Saracoğlu, Ali̇ Arslan Dönmez, Akito Nagatsu
Secondary Metabolites From Phlomis Syriaca And Their Antioxidant Activities, Ü. Şebnem Harput, İhsan Çaliş, İclal Saracoğlu, Ali̇ Arslan Dönmez, Akito Nagatsu
Turkish Journal of Chemistry
An iridoid glucoside, lamiide (1); 4 phenylethanoid glycosides, acteoside (2), \beta-OH acteoside (3), leucosceptoside A (4) and samioside (5); a caffeic acid ester, chlorogenic acid (6); 2 flavone glucosides, luteolin-7-O-glucopyranoside (7) and chrysoeriol-7-O-glucopyranoside (8); and a flavanone aglycone, naringenin (9), were isolated from the aerial parts of Phlomis syriaca. The structures of the isolated compounds were elucidated by means of spectroscopic (UV, IR, 1D- and 2D-NMR, and FAB-MS) methods. Free radical scavenging activity of the isolated compounds was determined using the radical 2,2-diphenyl-1-picrylhydrazyl (DPPH), spectroscopically.
Iridoid, Flavonoid, And Phenylethanoid Glycosides From Wiedemannia Orientalis, Zühal Güvenalp, Hi̇lal Özbek, Türesi̇n Ünsalar, Cavi̇t Kazaz, L. Ömür Demi̇rezer
Iridoid, Flavonoid, And Phenylethanoid Glycosides From Wiedemannia Orientalis, Zühal Güvenalp, Hi̇lal Özbek, Türesi̇n Ünsalar, Cavi̇t Kazaz, L. Ömür Demi̇rezer
Turkish Journal of Chemistry
Five iridoid glycosides, lamiide, ipolamiide, ipolamiidoside, 6\beta-hydroxyipolamiide, and 5-hydroxy-8-epi-loganin; 5 flavonoid glycosides, apigenin 7-O-\beta-glucopyranoside, luteolin 5-O-\beta- glucopyranoside, isorhamnetin 3-O-rutinoside, quercetin 3-O-rutinoside, and apigenin 7-O-(6''-O-trans-p-coumaroyl) \beta-glucopyranoside; and a phenylethanoid glycoside, acteoside (= verbascoside), were isolated from the aerial parts of Wiedemannia orientalis (Lamiaceae). Their structures were identified using spectral methods (UV, 1D- and 2D-NMR, and EI-MS).
Electrochemical Synthesis Of N-Methylpyrrole And N-Methylcarbazole Copolymer On Carbon Fiber Microelectrodes, And Their Characterization, A. Sezai̇ Saraç, Erkan Doğru, Murat Ateş, Eli̇f Altürk Parlak
Electrochemical Synthesis Of N-Methylpyrrole And N-Methylcarbazole Copolymer On Carbon Fiber Microelectrodes, And Their Characterization, A. Sezai̇ Saraç, Erkan Doğru, Murat Ateş, Eli̇f Altürk Parlak
Turkish Journal of Chemistry
Copolymer films of N-methylpyrrole (N-MPy) and N-methylcarbazole (N-MCz) were synthesized electrochemically onto single carbon fiber microelectrodes (CFMEs). Deposition conditions on the carbon fiber, influence of the monomer concentrations on the copolymerization of P[N-methylpyrrole-co-N-methylcarbazole] P[N-MPy-co-N-MCz], and the electrochemistry of the resulting homopolymer and copolymers were studied using cyclic voltammetry, FTIR-ATR, in-situ spectroelectrochemistry, a UV-vis spectrophotometer, and a 4-point probe conductometer. The effects of current density, supporting electrolyte type, temperature, and monomer concentrations on the formation of the film were studied. Redox parameters and stability of charged films were obtained by cyclic voltammetry. The most stable copolymer was obtained in lithium perchlorate-acetonitrile …
Synthesis, Characterization, Crystal Structure And Thermal Behavior Of N'-(4-Chlorobenzoyl)-N,N-Di-N-Butylthiourea And Its Nickel Complex, Hakan Arslan, Ulrich Flörke, Nevzat Külcü, Esra Kayhan
Synthesis, Characterization, Crystal Structure And Thermal Behavior Of N'-(4-Chlorobenzoyl)-N,N-Di-N-Butylthiourea And Its Nickel Complex, Hakan Arslan, Ulrich Flörke, Nevzat Külcü, Esra Kayhan
Turkish Journal of Chemistry
We report the synthesis, structural characterization and thermal behavior of N'-(4-chlorobenzoyl)-N,N-di-n-butylthiourea (HL) and its nickel complex (NiL_2). Some physical properties of the prepared compounds were investigated using elemental analyses, IR, ^1H-NMR, and magnetic susceptibility. The molecular structures of HL and NiL_2 were determined by single crystal X-ray diffraction. HL is a monoclinic, space group P2_1/c with a = 10.7457(5) Å, b = 15.5909(8) Å, c = 10.4536(5) Å, \beta = 104.398(1)°, and V = 1696.34(14) Å^3 with Z = 4 for d_{calc} = 1.280 g/cm^3. NiL_2 is a triclinic, space group P-1 with a = 8.561(3) Å, b = 16.643(6) …
Chemistry Of Bicyclic Endoperoxides Derived From Dihydropyridine Derivatives: Attempted Synthesis Of Polyhydroxypiperidine Derivatives, Emi̇ne Salamci, Beyhan Bayram, Meti̇n Balci
Chemistry Of Bicyclic Endoperoxides Derived From Dihydropyridine Derivatives: Attempted Synthesis Of Polyhydroxypiperidine Derivatives, Emi̇ne Salamci, Beyhan Bayram, Meti̇n Balci
Turkish Journal of Chemistry
To achieve the synthesis of azasugar derivatives with the utilization of singlet oxygen, pyridine was used as the starting material. The reduction of pyridine followed by a singlet oxygen reaction afforded cyclic aza-endoperoxides (14 and 16). However, many attempts were made to convert the aza-endoperoxides to the corresponding di- and triacetates without success. However, the base-catalyzed rearrangement of 14 gave unprecedented rearrangement products 23 and 24.