Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- 1 (98)
- 2 (83)
- Synthesis (61)
- Adsorption (55)
- Antimicrobial activity (47)
-
- 3 (45)
- Phthalocyanine (35)
- Antibacterial activity (31)
- Molecular docking (30)
- Cytotoxicity (28)
- Preconcentration (26)
- Cyclic voltammetry (25)
- Palladium (25)
- Voltammetry (25)
- Schiff base (24)
- Spectrophotometry (24)
- Copper (23)
- Fluorescence (23)
- Lamiaceae (22)
- DFT (20)
- Kinetics (20)
- Antioxidant activity (19)
- Antioxidant (18)
- Cadmium (18)
- Chitosan (18)
- Nanoparticles (18)
- Photocatalysis (18)
- Antimicrobial (17)
- Catalyst (16)
- Electrospinning (16)
- Publication Year
Articles 2071 - 2100 of 2720
Full-Text Articles in Chemistry
Synthesis, Characterization And Genotoxicity Of Platinum(Ii)Complexes With Subtituted Benzimidazole Ligands, Özteki̇n Algül, Berri̇n Özçeli̇k, Ufuk Abbasoğlu, Fatma Gümüş
Synthesis, Characterization And Genotoxicity Of Platinum(Ii)Complexes With Subtituted Benzimidazole Ligands, Özteki̇n Algül, Berri̇n Özçeli̇k, Ufuk Abbasoğlu, Fatma Gümüş
Turkish Journal of Chemistry
Five Pt(II) complexes with the ligands 2-ethyl-/ or-benzyl-/ or-phenoxymethyl- and 1-methyl-2-hydroxymethyl- and 1-methyl-2-phenyl- benzimidazoles were synthesized and characterized by elemental analysis, and IR and ^1H-NMR spectra and evaluated for their in vitro genotoxic activities by Rec-Assay test. Based on the data obtained in this study, the Pt(II) complexes tested might be taken into consideration as promising antitumor compounds.
Development And Characterization Of A Cationic Emulsion Formulation As A Potential Pdna Carrier System, Kudret Di̇lşat Barut, Fatma Fi̇li̇z Coşkun Ari, Fi̇li̇z Öner
Development And Characterization Of A Cationic Emulsion Formulation As A Potential Pdna Carrier System, Kudret Di̇lşat Barut, Fatma Fi̇li̇z Coşkun Ari, Fi̇li̇z Öner
Turkish Journal of Chemistry
The development of efficient and stable carriers for the delivery of DNA to the body is becoming an increasingly important issue in the fields of gene therapy and vaccination. The present study was designed to prepare an emulsion-based gene delivery system. Oil-in-water emulsions containing cetyltrimethylammonium bromide (CTAB) as a cationic surfactant and Pluronic F-68 as a nonionic co-surfactant were formulated and their physical characteristics were investigated. The cationic emulsion, referred to as B13d, containing a liquid crystal phase, was found to be stable and suitable for parenteral application. Complex formation between pGL3 plasmid DNA and B13d emulsion achieved at the …
Secondary Metabolites Of Phlomis Viscosa And Their Biological Activities, İhsan Çaliş, Hasan Kirmizibekmez, John A. Beutler, Ali̇ Arslan Dönmez, Funda Nuray Yalçin, Ekrem Kiliç, Meral Özalp, Peter Rüedi, Deni̇z Taşdemi̇r
Secondary Metabolites Of Phlomis Viscosa And Their Biological Activities, İhsan Çaliş, Hasan Kirmizibekmez, John A. Beutler, Ali̇ Arslan Dönmez, Funda Nuray Yalçin, Ekrem Kiliç, Meral Özalp, Peter Rüedi, Deni̇z Taşdemi̇r
Turkish Journal of Chemistry
Further phytochemical studies on the aerial parts of Phlomis viscosa (Lamiaceae) led to the isolation of 24 compounds: 3 iridoid glycosides, 10 phenylethanoid glycosides, a megastigmane glycoside and a hydroquinone glycoside, as well as 2 lignan glucosides and 7 neolignan glucosides, 1 of which is new (17b). Compound 17b was obtained as a minor component of an inseparable mixture (2:1) of 2 neolignan glucosides (17a/b), and characterized as 3',4-O-dimethylcedrusin 9-O-\beta -glucopyranoside. Full NMR data of the known 8-O-4' neolignan glucoside, erythro-1-(4-O-\beta-glucopyranosyl-3-methoxyphenyl)- 2-{2-methoxyl-4-[1-(E)-propene-3-ol]-phenoxyl}-propane-1,3-diol (18) are also reported. All isolated compounds were screened for cell growth inhibition versus 3 tumor cell lines …
The Synthesis And Applications Of Cr-Doped Glymo And Glymo/Damo Surface Coating Systems For Absorbing Uv-Light By Sol-Gel Process, Meltem Asi̇ltürk, Funda Sayilkan, Gali̇p İçduygu, Hi̇kmet Sayilkan
The Synthesis And Applications Of Cr-Doped Glymo And Glymo/Damo Surface Coating Systems For Absorbing Uv-Light By Sol-Gel Process, Meltem Asi̇ltürk, Funda Sayilkan, Gali̇p İçduygu, Hi̇kmet Sayilkan
Turkish Journal of Chemistry
A new glass coating system, containing \gamma- glycidoxypropyltrimethoxysilane/Cr^{3+} (system I:GLYMO/ Cr^{3+}) and \gamma-glycidoxypropyltrimethoxysilane/N-aminoethyl-3- aminopropyltrimethoxysilane/Cr^{3+} (system II:GLYMO/DAMO/Cr^{3+}), was synthesized by the sol-gel technique for UV light absorption applications. UV-visible spectroscopy (UV-VIS) was utilized to investigate the optical properties of coating materials. Especially system II showed very low transmission in the UV wavelength regions (300--400 nm) after thermal treatment of the coated surface. The UV transmission property of surfaces did not change at 80, 100, 450 or 500 °C, but a T value as low as 0.07% was obtained between 150 and 450 °C.
Kinetics Study Of Lead Ion Adsorption On Active Carbon, Riaz Qadeer, Sohail Akhtar
Kinetics Study Of Lead Ion Adsorption On Active Carbon, Riaz Qadeer, Sohail Akhtar
Turkish Journal of Chemistry
The kinetics of the adsorption of lead ions on active carbon from aqueous solutions was studied at room temperature at different lead ion concentrations (i.e. 0.1-0.5 g/L). The kinetics of the lead ion adsorption on active carbon is explained through mass transfer adsorption phenomena and the rate determining step was found to be film diffusion
Synthesis And Complex Formation Of Some Novel Vic-Dioxime Derivatives Of Hydrazones, Nursabah Sarikavakli, Gazi̇ İrez
Synthesis And Complex Formation Of Some Novel Vic-Dioxime Derivatives Of Hydrazones, Nursabah Sarikavakli, Gazi̇ İrez
Turkish Journal of Chemistry
Three novel vic-dioxime compounds and their transition metal complexes were synthesized for the first time. These ligands are anti-glyoximehydrazine (GH_2), anti-2-pyridinealdehydeglyoxime hydrazone (PyGH_2) and anti-2-furancarboxaldehydeglyoxime hydrazone (FGH_2). The synthesized anti-glyoximehydrazine was reacted with 2-pyridinealdehyde or 2-furancarboxaldehyde to obtain the PyGH_2 and FGH_2 ligands. Mononuclear complexes of these ligands with a metal-ligand ratio of 1:2 were prepared with Ni(II), Co(II) and Cu(II) ions. The structures of the ligands and complexes were determined by ^1H n.m.r, i.r spectroscopy and elemental analytical techniques.
Anhydrous Proton Conductive Polystyrene Sulfonic Acid Membranes, Ayhan Bozkurt
Anhydrous Proton Conductive Polystyrene Sulfonic Acid Membranes, Ayhan Bozkurt
Turkish Journal of Chemistry
A novel anhydrous proton conducting polymer electrolyte based on polystyrene sulfonic acid, PSSA and benzimidazole (BnIm) was synthesized. The PSSA-BnIm interactions were studied by FT-IR. The thermal properties of the blends were investigated by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). The proton conductivities of these materials were measured by AC impedance technique. The conductivities of these materials increase with increasing BnIm content and temperature and maximum conductivity was found to be approximately 5 \times 10^{-4} S/cm at 150 °C.
Synthesis And Characterization Of New Triheterocyclic Compounds Consisting Of 1,2,4-Triazol-3-One, 1,3,4-Thiadiazole And 1,3,4-Oxadiazole Rings, Nesli̇han Demi̇rbaş
Synthesis And Characterization Of New Triheterocyclic Compounds Consisting Of 1,2,4-Triazol-3-One, 1,3,4-Thiadiazole And 1,3,4-Oxadiazole Rings, Nesli̇han Demi̇rbaş
Turkish Journal of Chemistry
A series of acetic acid derivatives (2a-c) was synthesized by the condensation of compounds 1a-c with chloroacetic acid. The treatment of carboxylic acid derivatives with thiosemicarbazide in phosphorus oxychloride and subsequent diazotation of the products (3a-c) afforded 5-alkyl-2-[(5-chloro-1,3,4-thiadiazol-2-yl)methyl]- 2,4-dihydro-3H-1,2,4-triazol-3-one derivatives (4a-c). The treatment of compounds 4a-c with thiourea produced 5-alkyl-2-[(5-mercapto-1,3,4- thiadiazol-2-yl)methyl]-2,4-dihydro-3H-1,2,4-triazol-3-one derivatives (5a-c). Subsequently, compounds 5a-c were converted to acid hydrazides by treatment with hydrazine hydrate after esterification (7a-e). Moreover, the reaction of compounds 7a-c with carbon disulfite in the presence of KOH afforded 5-alkyl-2-[(5-\{[(5- mercapto-1,3,4-oxadiazol-2-yl)methyl]thio\}-1,3,4-thiadiazol-2-yl)methyl]- 2,4-dihydro-3H-1,2,4-triazol-3-ones (8a-c).
Synthesis Of Some New Isoxazolidines By 1,3-Dipolar Cycloaddition Reaction Of Nitrones And Olefins, Akbar Mobinikhaledi, Naser Forughifar, Zahra Kalate
Synthesis Of Some New Isoxazolidines By 1,3-Dipolar Cycloaddition Reaction Of Nitrones And Olefins, Akbar Mobinikhaledi, Naser Forughifar, Zahra Kalate
Turkish Journal of Chemistry
A series of new isoxazolidines 5a-j were synthesized by 1,3-dipolar cycloaddition reaction of different nitrones with substituted olefins under reflux condition. The yields of products following recrystallization from absolute ethanol were of the order of 40%-66%. IR, NMR and mass spectroscopies were used for identification of these compounds.
Synthesis Of Some Novel Optically Active Isocoumarin And 3,4-Dihydroisocoumarin Containing L-Valine And L-Leucine Moieties, Khosrow Zamani, Khalil Faghihi, Satar Ebrahimi
Synthesis Of Some Novel Optically Active Isocoumarin And 3,4-Dihydroisocoumarin Containing L-Valine And L-Leucine Moieties, Khosrow Zamani, Khalil Faghihi, Satar Ebrahimi
Turkish Journal of Chemistry
Phthalic anhydride was reacted with L-Valine and L-Leucine in a mixture of acetic acid and pyridine at room temperature, and then was refluxed at 90-100 °C and N-phthaloyl-L-valine or N-phthaloyl-L-leucine were obtained in quantitative yields. The imide-acids were converted to N-phthaloyl-L-valine acid chloride and N-phthaloyl-L-leucine acid chloride by reaction with thionyl chloride. Then 2 new derivatives of the chiral isocoumarin with L-valine and L-leucine moieties were synthesised by the condensation reaction of homophthalic acid with respective imide-acid chloride. Furthermore these isocoumarins were converted to 2 new chiral substituted 3,4-dihydroisocoumarins. Biological screening tests reveal that the compounds (3a, 9a) have not …
Synthesis And Antimicrobial Activities Of Some New Flavonyl Pro-Drug Esters Of Ampicillin, Meltem Ceylan Ünlüsoy, Nurten Altanlar, Rahmi̇ye Ertan
Synthesis And Antimicrobial Activities Of Some New Flavonyl Pro-Drug Esters Of Ampicillin, Meltem Ceylan Ünlüsoy, Nurten Altanlar, Rahmi̇ye Ertan
Turkish Journal of Chemistry
A new series of flavonyl pro-drug esters of ampicillin (Va-b) was prepared by condensing the appropriate bromomethyl flavone with ampicillin trihydrate potassium salt. Flavone derivatives and ampicillin both have good antibacterial activity. The synthesized compounds were tested for their antifungal and antibacterial activities in vitro. Both of the compounds were active against Candida krusei and Staphylococcus aureus.
Synthesis And In Vitro Antimicrobial And Cytotoxicity Activities Of 2-[(2-Nitro-1-Phenylalkyl)Thio]Benzoic Acid Derivatives, Mehtap Gökçe, Semra Utku, Erdoğan Berçi̇n, Berri̇n Özçeli̇k, Taner Karaoğlu, Ni̇ngur Noyanalpan
Synthesis And In Vitro Antimicrobial And Cytotoxicity Activities Of 2-[(2-Nitro-1-Phenylalkyl)Thio]Benzoic Acid Derivatives, Mehtap Gökçe, Semra Utku, Erdoğan Berçi̇n, Berri̇n Özçeli̇k, Taner Karaoğlu, Ni̇ngur Noyanalpan
Turkish Journal of Chemistry
In this research 14 compounds were tested for their antimicrobial activity. The synthesis of 7 compounds corresponding to 2-[(2-nitro-1-phenyl-propyl)thio]benzoic acids 4 has not been reported before and 7 compounds corresponding to 2-[(2-nitro-1-phenyl-ethyl) thio]benzoic acid 3 were reported by our research group. The antibacterial activity of the title compounds was evaluated by 2 Gram (+) (Staphylococcus aureus, Bacillus subtilis) and 2 Gram (-)(Pseudomonas aeruginosa, Escherichia coli) microorganisms. The antifungal activity of the compounds was also determined against yeast-like fungi (Candida albicans, C. krusei). For antibacterial activity, ampicillin and for antifungal activity, fluconazole and ketoconazole have been used as reference compounds. All …
Synthesis, Characterization And Primary Antimicrobial Activity Evaluation Of 3-Phenyl-6-Methyl-4(3h)-Quinazolinone-2-Yl-Mercaptoacetic Acid Arylidenehydrazides, Aysel Gürsoy, Banu Ünal, Ni̇lgün Karali, Gülten Ötük
Synthesis, Characterization And Primary Antimicrobial Activity Evaluation Of 3-Phenyl-6-Methyl-4(3h)-Quinazolinone-2-Yl-Mercaptoacetic Acid Arylidenehydrazides, Aysel Gürsoy, Banu Ünal, Ni̇lgün Karali, Gülten Ötük
Turkish Journal of Chemistry
3-Phenyl-6-methyl-4(3H)-quinazolinone-2-yl-mercaptoacetic acid hydrazide (3) was reacted with substituted aldehydes in absolute ethanol to obtain a new series, 3-phenyl-6-methyl-4(3H)-quinazolinone- 2-yl-mercaptoacetic acid arylidenehydrazides (4a-q). The structures of 4a-q were elucidated by elemental analyses and from spectrometric (UV, IR, ^1H-NMR, ^{13}C-NMR and EIMS) data. Then 4a-q were evaluated for antibacterial, antifungal and antitubercular activities. No significant activity was observed against the selected microorganisms.
Examination Of Some Organic Explosives By Ion Mobility Spectrometry (Ims), Hülya Koyuncu, Ertan Seven, Ayla Çalimli
Examination Of Some Organic Explosives By Ion Mobility Spectrometry (Ims), Hülya Koyuncu, Ertan Seven, Ayla Çalimli
Turkish Journal of Chemistry
The increase in terrorist activities committed using explosives in recent years has generated the need for improved analytical methods that can accurately and quickly identify explosives and their residues. In this study such an analytical method is evaluated. In the first phase of the study, standard solutions and a standard mixture solution of TNT (2,4,6-trinitrotoluene), RDX (1,3,5-trinitro-1,3,5-triazocyclohexane), PETN (pentaerythritoltetranitrate) and TETRYL (2,4,6-trinitrophenylmethylnitramine) were examined using ion mobility spectrometry (IMS). In the second phase, qualitative analysis of a real explosion residue was carried out and the explosive material used in the bomb was identified by analysing the acetone extract. In the …
Non-Steroidal Anti-Inflammatory Drugs (Nsaids) As Donor Ligands In Organotin(Iv) Derivatives: Synthesis, Spectroscopic Characterization And Biological Applications, Saira Shahzadi, Khadija Shahid, Saqib Ali, Mohammad Mazhar, Amin Badshah, Ejaz Ahmed, Abdul Malik
Non-Steroidal Anti-Inflammatory Drugs (Nsaids) As Donor Ligands In Organotin(Iv) Derivatives: Synthesis, Spectroscopic Characterization And Biological Applications, Saira Shahzadi, Khadija Shahid, Saqib Ali, Mohammad Mazhar, Amin Badshah, Ejaz Ahmed, Abdul Malik
Turkish Journal of Chemistry
Some new di- and tri-organotin(IV) derivatives of 4 different non-steroidal anti-inflammatory drugs (NSAIDs) with the general formulae R_2SnL_2 and R_3SnL (where R = n-C_{8}H_{17} and C_6H_5CH_2) and L = 2-[(2,3-dimethylphenyl)amino]benzoic acid, 2-(2-fluoro-4-biphenyl)propionic acid, 2-(4-isobutylphenyl) propionic acid and 2-(3-benzoylphenyl)-propionic acid were synthesized. These compounds were structurally characterized by infrared and multinuclear NMR (^1H, ^{13}C, ^{119}Sn) spectroscopies and mass spectrometry. The isotopic effect of tin was studied by comparison of experimental data with the simulated isotopic pattern using the Chemtool software package. These compounds were also screened against different animal and plant pathogens to study their biological activity. LD_{50} data show that …
New Complexes Of Organotin(Iv) 2-(N-Maleoylamino)-2-Methylpropanoate: Synthesis, Spectroscopic Characterization And Biological Activity, Sajjad Ahmad, Saqib Ali, Saira Shahzadi, Fiaz Ahmed, Khalid Mohammed Khan
New Complexes Of Organotin(Iv) 2-(N-Maleoylamino)-2-Methylpropanoate: Synthesis, Spectroscopic Characterization And Biological Activity, Sajjad Ahmad, Saqib Ali, Saira Shahzadi, Fiaz Ahmed, Khalid Mohammed Khan
Turkish Journal of Chemistry
Organotin(IV) complexes of 2-(N-maleoylamino)-2-methylpropanoate were prepared by treating the ligand acid with diorganotin dichloride and triorganotin chloride in 1:2 and 1:1 molar ratios, respectively. These reactions proceeded smoothly to completion and the complexes formed were characterized by elemental analysis, infrared, multinuclear NMR (^1H, ^{13}C, ^{119}Sn) and mass spectrometry. The biological activities of the tin complexes were studied by screening the compounds against various animal and plant pathogens. These results show that triorganotin(IV) carboxylates are more active against the animal and plant pathogens tested as compared to diorganotin dicarboxylates.
Synthesis Of Some New Dihalophenyl- And Dihalobenzylisocoumarins And Their (Dl)-3,4-Dihydroderivatives, Zahid Shafiq, Muhammad Arfan, Nasim Hasan Rama, Shahid Hameed, Ghulam Abbas, Muhammad Tahir Hussain
Synthesis Of Some New Dihalophenyl- And Dihalobenzylisocoumarins And Their (Dl)-3,4-Dihydroderivatives, Zahid Shafiq, Muhammad Arfan, Nasim Hasan Rama, Shahid Hameed, Ghulam Abbas, Muhammad Tahir Hussain
Turkish Journal of Chemistry
3-Dihalophenyl- and dihalobenzylisocoumarins (3a-c) were synthesized by condensation of homophthalic acid (1) with dihalobenzoyl- and dihalophenylacetyl chlorides (2a-c), respectively. The alkaline hydrolysis of these isocoumarins (2a-c) afforded keto-acids (4a-c). (dl)-3-(Dihalophenyl)- and (dl)-3-(dihalobenzyl)- 3,4-dihydroisocoumarins (6a-c) were obtained by reduction of keto-acids (4a-c) to racemic hydroxy-acids (5a-c) followed by cyclodehydration using acetic anhydride.
Determination Of Cadmium, Copper, Iron, Manganese, Lead And Zinc In Lichens And Botanic Samples By Electrothermal And Flame Atomic Absorption Spectrometry, Orhan Acar, Sümer Özvatan, Murat İli̇m
Determination Of Cadmium, Copper, Iron, Manganese, Lead And Zinc In Lichens And Botanic Samples By Electrothermal And Flame Atomic Absorption Spectrometry, Orhan Acar, Sümer Özvatan, Murat İli̇m
Turkish Journal of Chemistry
Within the framework of the International Atomic Energy Agency (IAEA) Analytical Quality Control Service (AQCS) Chemistry Unit a research program was initiated for the identification of trace elements such as Cd, Cu, Fe, Mn, Pb and Zn in IAEA lichen-338 for a proficiency test (PT). This was to evaluate the possibility of using lichens as biomonitors of trace elements in atmospheric pollution. Pyrolysis and atomization temperatures, atomization and background profiles, detection limits and characteristic masses of analytes in lichen samples with Ni, Ni + Pd and Ni + Pd + tartaric acid (TA) modifier mixture, and without any modifiers were …
Anodic Stripping Voltammetric Behavior Of Mercury In Chloride Medium And Its Determination At A Gold Film Electrode, Füsun Okçu, F. Ni̇l Ertaş, H. İsmet Gökçel, Hüseyi̇n Tural
Anodic Stripping Voltammetric Behavior Of Mercury In Chloride Medium And Its Determination At A Gold Film Electrode, Füsun Okçu, F. Ni̇l Ertaş, H. İsmet Gökçel, Hüseyi̇n Tural
Turkish Journal of Chemistry
The electrochemical behavior of aqueous Hg(II) ions at a gold film electrode is described. The effects of supporting electrolyte and halide ions on the anodic stripping voltammetric behavior of Hg(II) ions was illustrated to prepare a basis for the analysis in real samples with high saline content. The concentration ratio of metallic mercury to halide ions at the electrode surface determines the resulting peak characteristics. The peak potentials in particular shift in a more negative direction as the halide concentration increases. A comparative study with Cu(II) ions revealed that a different mechanism is involved in their reoxidation steps. Mercuric ions …
Synthesis Of Isomorphous Prototypic [Crfe_2o(Aco)_6(Tep)_3]Cl And [Crfe_2o(Aco)_6(Tmp)_3]Cl As Oxo-Centered Hetero Tri-Nuclear Carboxylate Complexes, Massoud Rafizadeh, Reza Tayebee, Vahid Amani
Synthesis Of Isomorphous Prototypic [Crfe_2o(Aco)_6(Tep)_3]Cl And [Crfe_2o(Aco)_6(Tmp)_3]Cl As Oxo-Centered Hetero Tri-Nuclear Carboxylate Complexes, Massoud Rafizadeh, Reza Tayebee, Vahid Amani
Turkish Journal of Chemistry
[CrFe_2O(AcO)_6(TEP)_3]Cl, (1), and [CrFe_2O(AcO)_6(TMP)_3]Cl, (2), were prepared by replacing 3 water molecules in the [CrFe_2O(AcO)_6(H_2O)_3]Cl complex with triethyl- and trimethyl-phosphates, respectively. FT-IR spectroscopy confirmed an oxo-centered, carboxylate-bridged, heteronuclear triangular structure for the title compounds. M_3O and MO_4 units adopted D_{3h} and D_{4h} local symmetry, respectively, and are surrounded by 6 bridging acetates with C_{2v} local symmetry.
O-Galloyl Flavonoids From Geranium Pyrenaicum And Their In Vitro Antileishmanial Activity, Di̇lek Erci̇l, Maeki Kaloga, Oliver A. Radtke, M. Koray Sakar, Albrecht F. Kiderlen, Herbert Kolodziej
O-Galloyl Flavonoids From Geranium Pyrenaicum And Their In Vitro Antileishmanial Activity, Di̇lek Erci̇l, Maeki Kaloga, Oliver A. Radtke, M. Koray Sakar, Albrecht F. Kiderlen, Herbert Kolodziej
Turkish Journal of Chemistry
From the aerial parts of Geranium pyrenaicum Burm., a new flavonol glycoside, kaempferol 3-O-(2'',3''-di-O-galloyl)-{\ss}-D-glucopyranoside (7), along with 6 known related glycosides [kaempferol 3-O-\beta-D-glucopyranoside (1), quercetin 3-O-\beta-D-glucopyranoside (2), quercetin 3-O-\beta-D-galactopyranoside (3), kaempferol 3-O-(2''-O-galloyl)-\beta-D-glucopyranoside (4), quercetin 3-O-(2''-O-galloyl)-\beta-D-glucopyranoside (5) and quercetin 3-O-(2'',3''-di-O-galloyl)-{\ss}-D-glucopyranoside (6)] and the ellagitannins corilagin (8) and tellimagrandin I (9) were isolated. Their structures were established from spectroscopic studies (UV, FAB-MS, ^1H and ^{13}C-NMR, ^1H-^1H COSY, HETCOR, HMBC). Compounds 1-7 were evaluated for antileishmanial activity against a panel of Leishmania species (L. major, L. donovani and L. amazonensis), indicating appreciable in vitro activities (IC_{50} 4-27 nM) when compared with Pentostam (IC_{50} …
New Alkoxyzinc Salts Mediated Chemoselective Transesterification Reactions, Necdet Coşkun, Mustafa Er
New Alkoxyzinc Salts Mediated Chemoselective Transesterification Reactions, Necdet Coşkun, Mustafa Er
Turkish Journal of Chemistry
A new chemoselective method for the transesterification of alkyl esters in the presence of in situ formed alkoxyzinc salts was developed. Electron-rich esters are less reactive than electron poor ones and this is the basis for the chemoselectivity of the reaction. Suggested mechanisms of the transesterification reactions are discussed.
Excellent And Convenient Procedures For Reduction Of Benzene And Its Derivatives, Ali̇ye Altundaş, Abdullah Menzek, Demet Demi̇rci̇ Gülteki̇n, Melek Karakaya
Excellent And Convenient Procedures For Reduction Of Benzene And Its Derivatives, Ali̇ye Altundaş, Abdullah Menzek, Demet Demi̇rci̇ Gülteki̇n, Melek Karakaya
Turkish Journal of Chemistry
Reductions of benzene, toluene, ortho-xylene, cumene, anisole and benzoic acid to corresponding nonconjugated dienes were realized at room temperature by gas NH_3 and Li. The reduced products were easily isolated because THF and dioxane were dissolved in the water. The yields and conversions of the reactions were 70-89% and 80-100%, respectively.
The Electroanalytical Determination Of Sodium Borohydride Using A Gold Electrode, Hüseyi̇n Çeli̇kkan, Hasan Aydin, M. Levent Aksu
The Electroanalytical Determination Of Sodium Borohydride Using A Gold Electrode, Hüseyi̇n Çeli̇kkan, Hasan Aydin, M. Levent Aksu
Turkish Journal of Chemistry
It was shown that square wave voltammetry, a technique with a much lower detection limit, could be successfully used in the detection of borohydride formed in alkaline medium. A Au electrode was found to be very suitable for this purpose. The detection limit was 3 x 10^{-5} M.
Analysis Of The Essential Oil Composition Of Sideritis Albiflora Using Direct Thermal Desorption And Headspace Gc-Ms Techniques, Gülaçti Topçu, Asli Barla, Ahmet C. Gören, Gökhan Bi̇lsel, Mi̇ne Bi̇lsel, Gülendam Tümen
Analysis Of The Essential Oil Composition Of Sideritis Albiflora Using Direct Thermal Desorption And Headspace Gc-Ms Techniques, Gülaçti Topçu, Asli Barla, Ahmet C. Gören, Gökhan Bi̇lsel, Mi̇ne Bi̇lsel, Gülendam Tümen
Turkish Journal of Chemistry
The main constituents of Sideritis albiflora were found to be trans-caryophyllene, \alpha-pinene, \beta-pinene, \gamma-cadinene, pulegone, and caryophyllene oxide by both thermal desorption GC/MS and headspace GC/MS techniques.
Polyphenolic Compounds And Antimicrobial Activity Of Quercus Aucheri Leaves, Mahmut Koray Sakar, Di̇dem Şöhretoğlu, Meral Özalp, Meli̇ke Eki̇zoğlu, Sonia Piacente, Cosimo Pizza
Polyphenolic Compounds And Antimicrobial Activity Of Quercus Aucheri Leaves, Mahmut Koray Sakar, Di̇dem Şöhretoğlu, Meral Özalp, Meli̇ke Eki̇zoğlu, Sonia Piacente, Cosimo Pizza
Turkish Journal of Chemistry
Chromatographic studies (CC, VLC, MPLC, and PTLC) on ethyl acetate extract from the leaves of Quercus aucheri yielded 2 flavonoids (quercetin 3-O-\alpha-L-arabinopyranoside (1), quercetin 3-O-\beta-D-galactopyranoside (2)) and 2 tannin precursors and a procyanidin [(isolated as peracetates of (+)-catechin (3a), (+)-gallocatechin (4a) and epicatechin-(4\beta \to 8)-catechin (5a))]. The structures of the compounds were elucidated by UV, 1D-NMR (^1H, ^{13}C, TOCSY) and 2D-NMR (COSY, HSQC, HMBC) techniques. Different extracts (80% MeOH, EtOAc, n-BuOH and H_2O) from the leaves of Q. aucheri were investigated for their antimicrobial activity against 2 Gram-positive and 2 Gram-negative bacteria and 3 yeast-like fungi by a broth microdilution …
Triterpene Saponins From Nigella Sativa L., Mustafa Kemal Taşkin, Özgen Alankuş Çalişkan, Hüseyi̇n Anil, Hassan Abou-Gazar, Ikhlas A. Khan, Erdal Bedi̇r
Triterpene Saponins From Nigella Sativa L., Mustafa Kemal Taşkin, Özgen Alankuş Çalişkan, Hüseyi̇n Anil, Hassan Abou-Gazar, Ikhlas A. Khan, Erdal Bedi̇r
Turkish Journal of Chemistry
Three known triterpene glycosides were isolated from the MeOH extract of dried and powdered seeds of Nigella sativa. The structures of the compounds were established as 3-O-[\beta-D-xylopyranosyl- (1 \to 3)-\alpha-L-rhamnopyranosyl-(1 \to 2)-\alpha -L-arabinopyranosyl]- 28-O-[\alpha-L-rhamnopyranosyl-(1 \to 4)-\beta-D-glucopyranosyl-(1 \to 6)- \beta-D-glucopyranosyl]-hederagenin (1), 3-O-[\alpha -L-rhamnopyranosyl- (1 \to 2)-\alpha-L-arabinopyranosyl]-28-O-[\alpha -L-rhamnopyranosyl-(1 \to 4)- \beta-D-glucopyranosyl-(1\to 6)-\beta-D-glucopyranosyl]-hederagenin (2), and 3-O-[\beta-D-xylopyranosyl- (1\to 3)-\alpha-L-rhamnopyranosyl-(1\to 2)-\alpha- L-arabinopyranosyl]-hederagenin (3) by means of chemical and spectral methods. Compound 2 was isolated for the first time from the genus Nigella.
Spectroscopic And Luminescence Properties Of An Isonicotinic Acid, Nurdoğan Can, Ahmet Ataç, Fehmi̇ Bardak, Şebnem Esen Sözerli̇ Can
Spectroscopic And Luminescence Properties Of An Isonicotinic Acid, Nurdoğan Can, Ahmet Ataç, Fehmi̇ Bardak, Şebnem Esen Sözerli̇ Can
Turkish Journal of Chemistry
An isonicotinic acid N-oxide Zn(II) compound was characterized on the basis of elemental analysis. FTIR spectra of the compound and free isonicotinic acid N-oxide (INO) were recorded in the range 4000--400 cm^{-1}. Cathodoluminescence (CL) spectra from the Zn(INO)_2 complex were recorded. The luminescence data were interpreted in terms of the emission band at 470 nm. The green luminescence (\sim 470 nm) arises from Zn^{2+} transition ^4T_1 (^4G) \to ^6A_1 (^6S). It shows a weak vibronic structure, and short lifetimes less than 150 \mu s. The lifetime and intensity of the signal are temperature dependent, and the parameters are reported for …
Interpretation Of Sorption Kinetics For Mixtures Of Reactive Dyes On Wool, Eli̇f Şahi̇n
Interpretation Of Sorption Kinetics For Mixtures Of Reactive Dyes On Wool, Eli̇f Şahi̇n
Turkish Journal of Chemistry
The equilibrium sorption isotherms of 3 reactive dyes (C. I. Reactive Yellow 84, C. I. Reactive Red 141, C. I. Reactive Blue 160) and their binary mixtures adsorbed on prewetted wool fiber were investigated. The kinetic studies were carried out at pH \le 7 and 80 °C in dye solutions containing 20 g/L NaCl. It was reported that binary mixtures of these reactive dyes have lower sorption values than the dyes alone, at the same dye concentration, pH and temperature. The isotherms obtained are Langmuir type. The rate parameters of adsorption kinetics decrease with increasing dye concentration.
A New Approach Towards (\Pm)-4-Ipomeanol And Its 2-Furyl Regioisomer, Jurgen Krauss, Franz Bracher, Doris Unterreitmeier
A New Approach Towards (\Pm)-4-Ipomeanol And Its 2-Furyl Regioisomer, Jurgen Krauss, Franz Bracher, Doris Unterreitmeier
Turkish Journal of Chemistry
The cytotoxic furan derivative (\pm)-4-ipomeanol (1) and its regioisomer (8) were prepared in a new and efficient way starting from commercially available furan derivatives. In both cases the key step was a regioselective solvolysis of the terminal double bond with trifluoroacetic anhydride and boron trifluoride. The resulting compounds were tested in an agar diffusion assay against several bacteria and fungi, but did not show significant activity.