Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- 1 (98)
- 2 (82)
- Synthesis (60)
- Adsorption (52)
- Antimicrobial activity (47)
-
- 3 (44)
- Phthalocyanine (34)
- Antibacterial activity (29)
- Cytotoxicity (27)
- Molecular docking (26)
- Preconcentration (26)
- Palladium (25)
- Voltammetry (25)
- Cyclic voltammetry (24)
- Copper (23)
- Fluorescence (23)
- Schiff base (23)
- Lamiaceae (22)
- Spectrophotometry (22)
- Antioxidant activity (19)
- DFT (19)
- Kinetics (19)
- Chitosan (18)
- Nanoparticles (18)
- Cadmium (17)
- Antioxidant (16)
- Electrospinning (16)
- Photocatalysis (16)
- 4-triazole (15)
- Antimicrobial (15)
- Publication Year
Articles 1291 - 1320 of 2628
Full-Text Articles in Physical Sciences and Mathematics
Ionic Liquid Mediated Synthesis, Reactions, And Insecticidal Activity Of 1-[(1h-Benzoimidazol-2-Yl)Amino]Spiro[Azetidine-4,4'-[4'H]Chroman]-2-Ones, Dr Kanti Sharma, Renuka Jain
Ionic Liquid Mediated Synthesis, Reactions, And Insecticidal Activity Of 1-[(1h-Benzoimidazol-2-Yl)Amino]Spiro[Azetidine-4,4'-[4'H]Chroman]-2-Ones, Dr Kanti Sharma, Renuka Jain
Turkish Journal of Chemistry
Ionic liquid mediated synthesis of novel heterocyclic compounds 1-[(1H-benzoimidazol-2-yl)amino]-2'-phenylspiro[azetidine- 4,4'-[4'H]chroman]-2-ones (3) and 1-[(1H-benzoimidazol-2-yl)amino]- 3-chloro-2'-phenylspiro[aze tidine-4,4'-[4'H] chroman]-2-ones (4) was accomplished by condensing substituted 2-hydrazino benzimidazole (1), flavanone (2), and acetyl chloride/chloroacetyl chloride in ionic liquid, [bmim]PF_6 with or without using catalyst in excellent yield (90%--95%). Further, compounds 3 and 4 were acylated with trifluoroacetic anhydride to give N-acylated products (5 and 10); 3 when treated with HCHO and (C_2H_5)_2NH gave Mannich bases (6) and with aldehydes afforded 3-arylidene-2-azetidinone (7). Compounds 4 underwent nucleophilic substitution with (i) KI (Finkelstein reaction) and (ii) phenols to give the corresponding iodo and phenoxy derivatives (8 …
Synthesis And Evaluation Of Acetylcholineesterase Inhibitory Potential And Antioxidant Activity Of Benzothiazine Derivatives, Durre Shahwar, Uzma Sana, Naeem Ahmad
Synthesis And Evaluation Of Acetylcholineesterase Inhibitory Potential And Antioxidant Activity Of Benzothiazine Derivatives, Durre Shahwar, Uzma Sana, Naeem Ahmad
Turkish Journal of Chemistry
The aim of the present study was to synthesize and characterize benzothiazine derivatives prepared by using 2-aminothiophenol and saccharine and in vitro screen their enzyme inhibition and antioxidant potential. Nine different derivatives were prepared and their structures were confirmed by spectral studies (EIMS, ^1 H and ^{13}C NMR). Enzyme inhibition potential of the synthesized compounds was evaluated by Ellman's method, while antioxidant activity was determined by DPPH and FRAP assays. All the derivatives showed remarkable activity against acetylcholine esterase with IC_{50} values in the range of 35.9--122.0 \mu M. All other derivatives, except compound 4a, were inactive towards DPPH radical. …
Synthesis And Antimicrobial Investigation Of Some 5h-Pyridazino[4,5-B]Indoles, İlker Avan, Alaetti̇n Güven, Kiymet Güven
Synthesis And Antimicrobial Investigation Of Some 5h-Pyridazino[4,5-B]Indoles, İlker Avan, Alaetti̇n Güven, Kiymet Güven
Turkish Journal of Chemistry
Synthesis and in vitro antimicrobial activities are reported for a series of 1,3,5-substituted 4-oxo-3,4-dihydro-5H-pyridazino[4,5-b]indole derivatives. Corresponding pyridazino[4,5-b]indoles were prepared from ethyl 3-formyl-1H-indole-2-carboxylate precursors and the functional group in question was installed with hydrazine and its derivatives. The purity and primary structures of pyridazino[4,5-b]indole were confirmed by IR, ^1 H NMR, and ^{13}C NMR spectroscopy and elemental analyses. All of the indoles were tested for in vitro antimicrobial activity against 8 isolates of bacteria and a fungus including Staphylococcus aureus NRRL B-767, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, Proteus vulgaris NRRL-B123, Salmonella typhimurium NRRL B-4420, Bacillus subtilis NRRL 744, …
Application Of Experimental Design On Determination Of Aluminum Content In Saline Samples By Adsorptive Cathodic Stripping Voltammetry, Si̇nan Yilmaz, Betül Öztürk, Durmuş Özdemi̇r, Ahmet Emi̇n Eroğlu, Fatma Ni̇l Ertaş
Application Of Experimental Design On Determination Of Aluminum Content In Saline Samples By Adsorptive Cathodic Stripping Voltammetry, Si̇nan Yilmaz, Betül Öztürk, Durmuş Özdemi̇r, Ahmet Emi̇n Eroğlu, Fatma Ni̇l Ertaş
Turkish Journal of Chemistry
Adsorptive cathodic stripping voltammetric determination of aluminum at ng mL^{-1} levels in salt samples based on the metal complexation with Calcon (1-(2-hydroxynaphthylazo)-2 naphthol-4-sulfonic acid) and the subsequent adsorptive deposition onto a hanging mercury drop electrode was studied. Central composite design was used as a design method. Several chemical and instrumental parameters (pH, ligand concentration, deposition time, deposition potential, and complexing time) were involved in the experimental design. Analytical parameters such as repeatability, linearity, and accuracy were also investigated and the detection limit was found as 0.32 ng mL^{-1}.
Theoretical Study On The Addition Reaction Between Propadienylidene And Methyleneimine, Mengyuan Wang, Yungang Chen, Shanshan Ding, Yingde Wang, Qianchao Cao, Xiaojun Tan, Jinsong Gu
Theoretical Study On The Addition Reaction Between Propadienylidene And Methyleneimine, Mengyuan Wang, Yungang Chen, Shanshan Ding, Yingde Wang, Qianchao Cao, Xiaojun Tan, Jinsong Gu
Turkish Journal of Chemistry
The reaction mechanism between propadienylidene and methyleneimine was systematically investigated employing the second-order Møller--Plesset perturbation theory (MP2) method with the 6 -- 31 + G* basis set. Geometry optimization, vibrational analysis, and energy property of the involved stationary points on the potential energy surface were calculated. The energies of the different species were corrected by single point energy calculations at the CCSD (T) // MP2 / 6 -- 31 + G* level. From the surface energy profile, one important initial intermediate characterized by a 3-membered ring structure was located via a transition state firstly. After that, 3 different products possessing …
Terpenoids, Essential Oil Composition, Fatty Acid Profile, And Biological Activities Of Anatolian Salvia Fruticosa Mill., Gülaçti Topçu, Mehmet Öztürk, Tuba Kuşman, Ayşe Asli Barla Demi̇rkoz, Ufuk Kolak, Ayhan Ulubelen
Terpenoids, Essential Oil Composition, Fatty Acid Profile, And Biological Activities Of Anatolian Salvia Fruticosa Mill., Gülaçti Topçu, Mehmet Öztürk, Tuba Kuşman, Ayşe Asli Barla Demi̇rkoz, Ufuk Kolak, Ayhan Ulubelen
Turkish Journal of Chemistry
The hexane and dichloromethane extracts, obtained by re-extraction of the methanol extract of Salvia fruticosa Mill., afforded 7 diterpenoids (carnosol, carnosic acid, carnosic acid 12-methyl ether, rosmadial, isorosmanol, ferruginol, and manool), 4 triterpenoids (\alpha -amyryltetracosanoate, oleanolic acid, ursolic acid, and erythrodiol), a steroid (3-acetylsitosterol), and a flavone (salvigenin). The galls (apples) of the collected plant were separately extracted with hexane to afford fatty acids composed mainly of oleic acid (29\%), palmitoleic acid (29\%), and stearic acid (23.20\%), which exhibited high anticholinesterase activity, particularly against BChE. The essential oil, obtained from the aerial parts of the plant, exhibited high AChE inhibitory …
Poly(4-Vinylpyridine)-Supported Dual Acidic Ionic Liquid: An Environmentally Friendly Heterogeneous Catalyst For The One-Pot Synthesis Of 4,4'-(Arylmethylene)Bis(3-Methyl-1-Phenyl-1h-Pyrazol-5-Ols), Kaveh Parvanak Boroujeni, Pegah Shojaei
Poly(4-Vinylpyridine)-Supported Dual Acidic Ionic Liquid: An Environmentally Friendly Heterogeneous Catalyst For The One-Pot Synthesis Of 4,4'-(Arylmethylene)Bis(3-Methyl-1-Phenyl-1h-Pyrazol-5-Ols), Kaveh Parvanak Boroujeni, Pegah Shojaei
Turkish Journal of Chemistry
A poly(4-vinylpyridine)-supported Brønsted ionic liquid was easily prepared from its starting materials and used as a novel, highly efficient, and reusable heterogeneous catalytic system for the synthesis of 4,4'-(arylmethylene)bis(3-methyl-1-phenyl-1H-pyrazol-5-ols) from the condensation reaction between aromatic aldehydes and 2 equivalents of 3-methyl-l-phenyl-5-pyrazolone.
A Kinetic Study Of Atom Transfer Radical Polymerization Of Styrene With Bis(2-Pyridyl)Ethylenedimethanimine Derivative Ligands, Hülya Arslan, Yasemi̇n Küçük, Ayfer Menteş, Meti̇n Hayri̇ Acar
A Kinetic Study Of Atom Transfer Radical Polymerization Of Styrene With Bis(2-Pyridyl)Ethylenedimethanimine Derivative Ligands, Hülya Arslan, Yasemi̇n Küçük, Ayfer Menteş, Meti̇n Hayri̇ Acar
Turkish Journal of Chemistry
Atom transfer radical polymerization (ATRP) of styrene was carried out with multidentate nitrogen-based ligands, namely N,N'-bis[phenyl(pyrid-2-yl)methylene] ethane-1,2-diamine (BPDA) and N,N'-bis[methyl(pyrid-2-yl)methylene] ethane-1,2-diamine (BMDA), and catalyst systems at catalyst/ligand molar ratios of 1/0.33, 1/0.5, 1/1, and 1/1.5 by using 2 different initiators, (1-bromoethyl)benzene (BEB) and ethyl-2-bromopropionate (EBP). Linear first-order kinetic plots were observed for ATRP of styrene upon using BPDA as a ligand with both initiators. Even though the linear slopes indicate that radical concentration remains constant during reactions, high molecular weights were obtained at low conversion and showed a linear relation thereafter. To investigate the molecular weight effect, reactions were also …
A New Anthracene Derivative Of Calix[4]Arene As A Fluorescent Chemosensor, Özlem Şahi̇n, Mustafa Şahi̇n, Nuri̇ye Koçak, Mustafa Yilmaz
A New Anthracene Derivative Of Calix[4]Arene As A Fluorescent Chemosensor, Özlem Şahi̇n, Mustafa Şahi̇n, Nuri̇ye Koçak, Mustafa Yilmaz
Turkish Journal of Chemistry
A new anthracene derivative of calix[4]arene was synthesized as a highly fluorescent compound. This compound was examined for its fluorescent properties towards different metal ions (Li^+, Na^+, Mg^{2+}, Ca^{2+}, Ba^{2+}, Ni^{2+}, Cu^{2+}, Zn^{2+}, Pb^{2+}) by UV and fluorescence spectroscopy. On complexation by alkaline earth metal cations and transition metal cations, the fluorescence spectrum was quenched. In particular, Ca^{2+} caused greater than 98% quenching of the anthracene derivative of calix[4]arene.
Synthesis Of 3,4-Diaryl-1-Phenyl-4,5-Dihydro-1h-Pyrazole-5-Carbonitriles Via 1,3-Dipolar Cycloaddition Reactions, Jayaroopa Prabhashankar, Vasanth Kumar Govindappa, Ajay Kumar Kariyappa
Synthesis Of 3,4-Diaryl-1-Phenyl-4,5-Dihydro-1h-Pyrazole-5-Carbonitriles Via 1,3-Dipolar Cycloaddition Reactions, Jayaroopa Prabhashankar, Vasanth Kumar Govindappa, Ajay Kumar Kariyappa
Turkish Journal of Chemistry
Nitrile imines generated by the oxidative dehydrogenation of aromatic aldehyde phenylhydrazones with chloramine-T as a catalytic dehydrogenating agent were trapped in situ by 4-methoxy cinnamonitrile to afford 3,4-diaryl-1-phenyl-4,5-dihydro-1H-pyrazole-5-carbonitrile in moderate to good yields. The structures of the cycloadducts were confirmed by spectral studies and elemental analysis.
Biodegradability Of Degradable Mulching Film In A Laboratory-Controlled Composting Test, Xuemei Zhang, Yaxi Huang, Deqiang Li, Zicheng Wen, Baoxun Sui, Zhiyong Liu
Biodegradability Of Degradable Mulching Film In A Laboratory-Controlled Composting Test, Xuemei Zhang, Yaxi Huang, Deqiang Li, Zicheng Wen, Baoxun Sui, Zhiyong Liu
Turkish Journal of Chemistry
A series of degradable films was prepared, and 2 formulas of polyethylene (PE) films with the highest degradable performance were experimentally determined. These films contained 3.43% and 0.44% stearate, and were denoted as PE-3 and PE-4, respectively. Their biodegradability was studied in a laboratory-controlled composting test using ordinary PE film (OPEF) as a control. Contrast composting experiments indicated that the biodegradability of untreated samples was very low, and that the biodegradation rates of PE films after natural aging were significantly higher. FT-IR analysis showed that OPEF changed little after the composting experiment, and that PE-3 and PE-4 showed a carbonyl …
Novel Flame Retardant Poly(Thiourea-Sulfone-Imide)S For High Temperature Applications: Synthesis And Characterization, Ghulam Waris, Humaira Masood Siddiqi, Lance Twyman, Rizwan Hussain, Zareen Akhter, Muhammad Saeed Butt
Novel Flame Retardant Poly(Thiourea-Sulfone-Imide)S For High Temperature Applications: Synthesis And Characterization, Ghulam Waris, Humaira Masood Siddiqi, Lance Twyman, Rizwan Hussain, Zareen Akhter, Muhammad Saeed Butt
Turkish Journal of Chemistry
The synthesis and polymerization of a novel diamine monomer, 1,1-(sulfonylbis (4,1-phenylene)) bis (thiourea) (SPT), with various aromatic dianhydrides were carried out. In addition, the fabrication of poly(thiourea-sulfone-imide)s (PTSIs) with noble thermal properties and flame retardancy was conducted. The structures of SPT and polymers were characterized by FT-IR, ^1H NMR, and ^{13}C NMR spectroscopy along with elemental analysis. Crystallinity, organosolubility, inherent viscosity, and gel permeation chromatographic measurements were taken as well. The amorphous nature was exhibited by PTSIs containing C=S and --SO_2- moieties in the backbone that were readily soluble in highly polar organic solvents. The inherent viscosities of PTSIs were …
Electrochemical Properties Of 1,3-Disubstituted Methyl Methoxy Phenyl-5-Phenylformazans And Comparison With Spectral Properties, Habi̇be Tezcan, Güler Ekmekci̇, Mehmet Levent Aksu
Electrochemical Properties Of 1,3-Disubstituted Methyl Methoxy Phenyl-5-Phenylformazans And Comparison With Spectral Properties, Habi̇be Tezcan, Güler Ekmekci̇, Mehmet Levent Aksu
Turkish Journal of Chemistry
In this study, electrochemical behaviors of formazans were investigated. The compounds contained CH_3 and OCH_3 groups at the o-, m-, and p-positions of the 1-phenyl ring and an OCH_3 group at the p-position of the 3-phenyl ring. Their electrochemical behaviors, such as the number of electrons transferred, diffusion coefficients, and heterogeneous rate constants, were studied by cyclic voltammetry, ultramicrodisk electrode, and chronoamperometry. Possible mechanisms were proposed based upon the data obtained. There was a correlation between the absorption and electrochemical properties. A linear correlation was obtained between \lambda_{\max} and E_{red2} and Hammett substituent coefficients with E_{red2} and k_s values.
A New Method For Calculating The Vibration-Rotation-Tunneling Spectra Of Molecular Clusters And Its Application To The Water Dimer, Mahi̇r Erteki̇n Ocak
A New Method For Calculating The Vibration-Rotation-Tunneling Spectra Of Molecular Clusters And Its Application To The Water Dimer, Mahi̇r Erteki̇n Ocak
Turkish Journal of Chemistry
A new method is developed for calculating the vibration-rotation-tunneling spectra of molecular clusters consisting of rigid monomers. The method is based on generation of optimized bases for each monomer. First, a sequential symmetry adaptation procedure is developed for relating the symmetries of monomer basis functions with the symmetries of the eigenstates of the cluster. Then this symmetry adaptation procedure is used in the generation of optimized bases and combining them for finding the eigenstates. Symmetry adaptation problems related to the generation of optimized bases are identified and solutions are suggested. The method is applied to the water dimer by using …
Synthesis And Characterization Of Ni(Ii) And Cu(Ii) Complexes Derived From Novel Phenolic Mannich Bases, Nurgün Büyükkidan, Sali̇h Özer
Synthesis And Characterization Of Ni(Ii) And Cu(Ii) Complexes Derived From Novel Phenolic Mannich Bases, Nurgün Büyükkidan, Sali̇h Özer
Turkish Journal of Chemistry
The novel phenolic Mannich bases 2,2'-(2-hydroxy-4,5- dimethylbenzylazanediyl)diethanol (1) and 2-((2-(4-(2-hydroxy-4,5- dimethylbenzyl)piperazin-1-yl)ethylamino)methyl)-4,5-dimethylphenol (2) have been synthesized in good yield by using a microwave-induced technique from 3,4-dimethylphenol and corresponding amines in the presence of formaldehyde. Metal complexes of 1 and 2 for Ni(II) (3 and 5) and for Cu(II) (4 and 6) have also been prepared and all compounds have been characterized by elemental and spectral analyses. Thermal, magnetic, and electronic studies have also been reported for metal complexes. Electronic spectra and magnetic susceptibility measurements suggested tetrahedral geometry for Ni(II) (3), square planar geometry for Cu(II) (4) complexes of 1, and octahedral …
New Secondary Metabolites From Croton Sparsiflorus Morong, Rashad Mehmood, Amna Bibi, Abdul Malik
New Secondary Metabolites From Croton Sparsiflorus Morong, Rashad Mehmood, Amna Bibi, Abdul Malik
Turkish Journal of Chemistry
Sparsifloamide (1), a new sphingolipid, and sparsifloside (2), a new diglyceride galactoside, have been isolated from the ethyl acetate soluble fraction of the 80% ethanolic extract of the whole plant of Croton sparsiflorus Morong. Their structures were assigned by ^1H- and ^{13}C-NMR spectra and DEPT, COSY, NOESY, HMQC, HMBC, and ESI-MS experiments.
Molecular Docking And Qsar Study On Imidazole Derivatives As 14 /Alpha -Demethylase Inhibitors, Asghar Davood, Maryam Iman
Molecular Docking And Qsar Study On Imidazole Derivatives As 14 /Alpha -Demethylase Inhibitors, Asghar Davood, Maryam Iman
Turkish Journal of Chemistry
14\alpha-Demethylase (CYP51) inhibitors have been widely used in the treatment of fungal infections. In this study, a series of imidazole derivatives with CYP51 inhibitory activity were subjected to a molecular docking study followed by quantitative structure-activity relationship (QSAR) analyses in search of the ideal physicochemical characteristics of potential CYP51 inhibitors. Desired imidazoles were built using the HyperChem program, and conformational studies were performed through a semiempirical method followed by the PM3 method. Docking study was performed using the AutoDock program on all of the compounds. Different QSAR descriptors were calculated using DRAGON, AutoDock, and HyperChem. Multilinear regression was used as …
Enaminonitriles In Heterocyclic Synthesis: Synthesis And Biological Evaluation Of Novel Indeno[2,1-B]Thiophene Derivatives, Ahmed A. Fadda, Abd El Galil M. Khalil, Eman H. Tawfik
Enaminonitriles In Heterocyclic Synthesis: Synthesis And Biological Evaluation Of Novel Indeno[2,1-B]Thiophene Derivatives, Ahmed A. Fadda, Abd El Galil M. Khalil, Eman H. Tawfik
Turkish Journal of Chemistry
No abstract provided.
Spectrophotometric Determination Of 3-Hydroxy-3-Methylglutaryl Coenzyme-A Reductase Inhibitors In Pharmaceutical Preparations, Gamze Ergi̇n, Sena Çağlar, Armağan Önal, Sidika Ertürk Toker
Spectrophotometric Determination Of 3-Hydroxy-3-Methylglutaryl Coenzyme-A Reductase Inhibitors In Pharmaceutical Preparations, Gamze Ergi̇n, Sena Çağlar, Armağan Önal, Sidika Ertürk Toker
Turkish Journal of Chemistry
Simple and accurate spectrophotometric methods are presented for the determination of five 3-hydroxy-3-methylglutaryl coenzyme-A (HMG-CoA) reductase inhibitors (statins), namely atorvastatin, fluvastatin, pitavastatin, rosuvastatin, and simvastatin, in pharmaceutical preparations. The methods are based on the reaction of drugs as n-electron donor with 7,7,8,8-tetracyanoquinodimethane as \pi-acceptors to give highly colored complex species. All variables were studied in order to optimize the reaction conditions. Beer's law was obeyed in the concentration ranges 4--20 \mu g mL^{-1}, 4--12 \mu g mL^{-1}, 0.8--2.4 \mu g mL^{-1}, 4--14 \mu g mL^{-1}, and 2.5--20 \mu g mL^{-1} for atorvastatin, fluvastatin, pitavastatin, rosuvastatin, and simvastatin, respectively. The proposed …
Removal Of Cr(Iii) And Cu(Ii) Using Oly(2-Chloroaniline)/Polyvinylidenefluoride Composite Cation-Exchange Membranes By Donnan Dialysis, Esengül Kir, Sabri̇ye Perçi̇n Özkorucuklu, Tuğba Sardohan Köseoğlu, Esi̇n Karamizrak
Removal Of Cr(Iii) And Cu(Ii) Using Oly(2-Chloroaniline)/Polyvinylidenefluoride Composite Cation-Exchange Membranes By Donnan Dialysis, Esengül Kir, Sabri̇ye Perçi̇n Özkorucuklu, Tuğba Sardohan Köseoğlu, Esi̇n Karamizrak
Turkish Journal of Chemistry
P2ClAn/PVDF composite membranes were prepared utilizing cation-exchange groups in the PVDF (polyvinylidenefluoride) membrane matrix by casting method. The poly(2-chloroaniline) (P2ClAn) was chemically synthesized with different dopant anions such as o-aminobenzene sulfonic acid (ABS) and sodium dodecyl sulfate (SDS). P2ClAn/PVDF membranes were extensively characterized for their surface morphology, thickness, ion-exchange capacity, SEM, AFM, and FTIR-ATR measurements. The SEM, AFM and FTIR-ATR pictures, comparing the original PVDF membrane support sheet to P2ClAn/PVDF composite membranes, indicate that the morphologies of the membranes are different. The membrane potential measurements were performed in various electrolyte solutions in order to observe the selectivity and stability of …
Synthesis And Cytotoxic Activity Of Some 2-(2,3-Dioxo-2,3-Dihydro-1h-Indol-1-Yl)Acetamide Derivatives, Özlem Akgül, Ayşe Hande Tari̇koğullari, Fadi̇me Aydin Köse, Petek Ballar Kirmizibayrak, Mehmet Varol Pabuççuoğlu
Synthesis And Cytotoxic Activity Of Some 2-(2,3-Dioxo-2,3-Dihydro-1h-Indol-1-Yl)Acetamide Derivatives, Özlem Akgül, Ayşe Hande Tari̇koğullari, Fadi̇me Aydin Köse, Petek Ballar Kirmizibayrak, Mehmet Varol Pabuççuoğlu
Turkish Journal of Chemistry
Isatin, 1H-indoline-2,3-dione, an endogenous compound, is also a synthetically versatile molecule that possesses a diversity of biological activities including anticonvulsant, antibacterial, antifungal, antiviral, anticancer, and cytotoxic properties. Based on the promising cytotoxic activity studies on N-substituted isatin derivatives, a series of 18 derivatives of 2-(2,3-dioxo-2,3-dihydro- 1H-indol-1-yl)-N-phenylacetamide were designed, synthesized, and characterized according to their analytical and spectral data. All of the compounds were evaluated for their cytotoxic activity against MCF7, A549, HeLa, and HEK293 cell lines by real time cell analyzer. Etoposide was used as a standard compound. Briefly, ortho substitutions gave better results compared to meta and para substitutions …
Synthesis And Characterization Of Thermally Stable Camphor-Based Polyimide--Clay Nanocomposites, Murat Yi̇ği̇t, Turgay Seçki̇n, Beyhan Yi̇ği̇t, Süleyman Köytepe
Synthesis And Characterization Of Thermally Stable Camphor-Based Polyimide--Clay Nanocomposites, Murat Yi̇ği̇t, Turgay Seçki̇n, Beyhan Yi̇ği̇t, Süleyman Köytepe
Turkish Journal of Chemistry
A new monomer was prepared from (1R,3S)-(+)-camphoric acid. Novel polyimide and polyimide--clay hybrid composites were developed from one-pot condensation reactions of this monomer and pyromellitic dianhyride. Polyimide-montmorillonite nanocomposites were prepared from solution of polyimide and with different weight percentages (1, 5, 10 wt %) of organo-modified montmorillonite (OM-MMT) using N-methyl-2-pyrrolidone (NMP) as aprotic solvent. The reactive organoclay was formed by using hexadecylpyridinium chloride as a swelling agent for silicate layers of montmorillonite. The polyimide--clay composites films (PI--MMT) were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD). All composites were subjected to differential scanning calorimetry …
Antimicrobial Activity And Chemical Composition Of The Essential Oils Of Mosses (Hylocomium Splendens (Hedw.) Schimp. And Leucodon Sciuroides (Hedw.) Schwägr.) Growing In Turkey, Tayyi̇be Beyza Cansu, Büşra Yayli, Turan Özdemi̇r, Nevzat Batan, Şengül Alpay Karaoğlu, Nuretti̇n Yayli
Antimicrobial Activity And Chemical Composition Of The Essential Oils Of Mosses (Hylocomium Splendens (Hedw.) Schimp. And Leucodon Sciuroides (Hedw.) Schwägr.) Growing In Turkey, Tayyi̇be Beyza Cansu, Büşra Yayli, Turan Özdemi̇r, Nevzat Batan, Şengül Alpay Karaoğlu, Nuretti̇n Yayli
Turkish Journal of Chemistry
In the present work, the volatiles of mosses [Hylocomium splendens (Hedw.) Schimp. (Hylocomiaceae) and Leucodon sciuroides (Hedw.) Schwägr. (Leucodontaceae)] have been investigated by GC-FID and GC/MS. Fifty-eight compounds in the oil of H. splendens, representing 75.4%, and 41 compounds in the oil of L. sciuroides, representing 87.6%, were identified. The major components were found to be \beta-pinene (11.6%) and \alpha-pinene (8.9%) in the oil of H. splendens, and nonanal (26.8%) and heptanal (13.7%) in the oil of L. sciuroides. The essential oil of H. splendens was rich in monoterpenes (30.8%), and aldehydes (49.9%) were the major constituents in the oil …
New Synthetic Methodology For Construction Of The 3,4-Dihydroquinolin-2-One Skeleton, Çağatay Dengi̇z, Meti̇n Balci
New Synthetic Methodology For Construction Of The 3,4-Dihydroquinolin-2-One Skeleton, Çağatay Dengi̇z, Meti̇n Balci
Turkish Journal of Chemistry
We hereby report a new method for preparation of 3,4-dihydroquinolin-2(2H)-one starting from the methyl 2-(2-carboxyethyl)benzoic acid. The acid functionality, adjacent to the methylene, was regiospecifically converted to the desired methyl ester and the remaining acid functionality was transferred into acyl azide. Curtius rearrangement of acyl azide followed by trapping with aniline and alcohols provided the corresponding urea and urethane derivatives. Hydrolysis of methyl ester groups gave the acids. Ring closure in the presence of thionyl chloride resulted in the formation of the 3,4-dihydroquinolin-2(2H)-one skeleton.
Study On Crystal Transformation Process Of Magnesium Carbonate Hydrate Based On Salt Lake Magnesium Resource Utilization, Juan Du, Zhen Chen, Yulong Wu, Mingde Yang, Jie Dang, Jianjun Yuan
Study On Crystal Transformation Process Of Magnesium Carbonate Hydrate Based On Salt Lake Magnesium Resource Utilization, Juan Du, Zhen Chen, Yulong Wu, Mingde Yang, Jie Dang, Jianjun Yuan
Turkish Journal of Chemistry
The crystal transformation process of magnesium carbonate hydrate by the reaction of magnesium sulfate (MgSO_4) with ammonium carbonate [(NH_4)_2CO_3] was investigated. MgSO_4 is one of the main magnesium resources of the Lop Nur salt lake in the Xinjiang Autonomous Region of China. Magnesium carbonate hydrates with different chemical compositions were prepared. The transformation process of the 2 crystals, MgSO_4 and (NH_4)_2CO_3, was analyzed by Raman spectroscopy, and the associated changes in crystal morphology were observed by scanning electron microscopy. The needle-like MgCO_3 \cdot 3H_2O transformed into sheet-like 4MgCO_3 \cdot Mg(OH)_2 \cdot 4H_2O when the temperature was increased from 323 K …
A One-Pot Strategy For Regioselective Synthesis Of 6-Aryl-3-Oxo-2,3-Dihydropyridazine-4-Carbohydrazides, Mehdi Rimaz, Hossein Mousavi
A One-Pot Strategy For Regioselective Synthesis Of 6-Aryl-3-Oxo-2,3-Dihydropyridazine-4-Carbohydrazides, Mehdi Rimaz, Hossein Mousavi
Turkish Journal of Chemistry
A simple and efficient method for the synthesis of 6-aryl-3-oxo-2,3-dihydropyridazine-4-carbohydrazide derivatives was developed. The synthesis was achieved via one-pot multicomponent reaction of arylglyoxals, dialkylmalonates, and hydrazine hydrate in pyridine at room temperature. This procedure features high regioselectivity, generally good to excellent yields, the use of easily available starting materials, and operational simplicity. This chemistry provides an efficient and promising synthetic strategy for diversity-oriented construction of the 6-arylpyridazinone skeleton.
An Efficient Ligand-Free Method For The Transfer Hydrogenation Of Ketones And Aldehydes Catalyzed By Different Complexes, Sedat Yaşar, Suzan Çeki̇rdek, Ni̇lay Akkuş Taş, Semi̇ha Yildirim, İsmai̇l Özdemi̇r
An Efficient Ligand-Free Method For The Transfer Hydrogenation Of Ketones And Aldehydes Catalyzed By Different Complexes, Sedat Yaşar, Suzan Çeki̇rdek, Ni̇lay Akkuş Taş, Semi̇ha Yildirim, İsmai̇l Özdemi̇r
Turkish Journal of Chemistry
A very efficient ligand-free method was developed for the transfer hydrogenation of ketones and aldehydes catalyzed by different metal complexes. With this catalytic system, the catalytic performance and catalytic stability of different Ir, Ru, and Pd complexes were more favorable than those of the previously reported systems for transfer hydrogenation. This ligand-free catalytic system showed good stability and excellent activity even with lower catalyst concentrations for the ketones and aldehydes tested.
Synthesis And Characterization Of New Chromogenic Substrates For Exoglycosidases: \Alpha-Glucosidase, \Alpha-Mannosidase, And \Beta-Galactosidase, Dumitru Petru Iga, Richard Schmidt, Silvia Iga, Corina Loredana Hotoleanu, Florentina Duica, Alina Nicolescu, Silvia Stefania Gitman
Synthesis And Characterization Of New Chromogenic Substrates For Exoglycosidases: \Alpha-Glucosidase, \Alpha-Mannosidase, And \Beta-Galactosidase, Dumitru Petru Iga, Richard Schmidt, Silvia Iga, Corina Loredana Hotoleanu, Florentina Duica, Alina Nicolescu, Silvia Stefania Gitman
Turkish Journal of Chemistry
Glycosides of 4-nitrocatechol (1,2-dihydroxy 4-nitrobenzene) with \alpha-D-glucopyranose and \alpha-D-mannopyranose were synthesized by the glycosylation of phenol with peracetylated sugars in the presence of BF_3\cdot OBu_2. The glycoside of 4-nitrocatechol with \beta-D-galactopyranose was prepared by the glycosylation of this phenol as sodium phenoxide with tetra-O-benzoyl-\alpha-D- galactopyranosyl bromide. The structure of the reaction products was confirmed by ^1 H and ^{13}C NMR spectra and by chemical analysis. The latter consisted of acidic hydrolysis, followed by ethyl ether extraction and colorimetric determination of 4-nitrocatechol in the ether phase and application of the anthrone method for the sugar in the water phase. The synthetic …
Potentiometric Determination Of Some Food Additives And Their Binding To A Polycationic Species Using Polyion Sensors, Nedi̇me Dürüst, Ali̇ Kayansalan
Potentiometric Determination Of Some Food Additives And Their Binding To A Polycationic Species Using Polyion Sensors, Nedi̇me Dürüst, Ali̇ Kayansalan
Turkish Journal of Chemistry
Polycation-sensitive membrane electrodes based on dinonylnaphthalene sulfonate (DNNS) were examined for the determination of some polyanions, namely xanthan (Xanth), alginate (Alg), carboxymethyl cellulose (CMC), and carrageenan (Carr). The potentiometric titrations of polyanionic analytes yielded sharp end points and correlative stoichiometries. After the determinations were successfully performed in saline, these polyanions were also determined in some food products consumed in Bolu (Turkey). In addition, the titration data were used to estimate the interactions between titrant and polyanionic analytes. The equilibrium constants, K_{eq}, and the number of titrant binding sites (n) per mole of analyte polyanion were calculated using Scatchard plots. The …
Electrochemistry Of 2,6-Diaminopurine On Multiwall Carbon Nanotube Modified Glassy Carbon Electrode, Ebru Mavi̇oğlu Ayan, Şükri̇ye Karabi̇beroğlu, Zekerya Dursun
Electrochemistry Of 2,6-Diaminopurine On Multiwall Carbon Nanotube Modified Glassy Carbon Electrode, Ebru Mavi̇oğlu Ayan, Şükri̇ye Karabi̇beroğlu, Zekerya Dursun
Turkish Journal of Chemistry
The electrochemical oxidation of 2,6-diaminopurine (2,6-DAP) was studied in pH 7.4 phosphate buffer solution on multiwall carbon nanotube modified glassy carbon electrode (MWCNT/GCE) over a temperature range of 20 to 50 °C using cyclic voltammetry. 2,6-DAP oxidation on MWCNT/GCE showed a well-defined and irreversible oxidation peak at about 0.72 V vs. Ag/AgCl at pH 7.4. The oxidation potential of 2,6-DAP linearly varied with pH over the range of 3.0 to 10.0 with a slope of --0.0547 V/pH, implying that 2 protons were accompanied by 2 electrons transferred in the electrochemical reaction. The activation energy, Ea, of oxidation reaction was found …