Browsing by Author "Akbas, Esvet"
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Correction Antibacterial and Antifungal Activities of New Pyrazolo[3,4-D]pyridazin Derivatives (Vol 41, Pg 904, 2006)(Elsevier France-editions Scientifiques Medicales Elsevier, 2006) Akbas, Esvet; Berber, IsmetArticle Antioxidant Properties of Ferulago Angulata and Its Hepatoprotective Effect Against N-Nitrosodimethylamine Oxidative Stress in Rats(Taylor & Francis Ltd, 2017) Kiziltas, Hatice; Ekin, Suat; Bayramoglu, Mahire; Akbas, Esvet; Oto, Gokhan; Yildirim, Serkan; Ozgokce, FevziContext: Ferulago angulata (Schlecht.) Boiss. (Apiaceae) (FASB) is used to treat liver diseases and has been used both as food and therapeutics by many cultures for thousands of years because of the natural antioxidant compounds. Objective: This study determines antioxidant properties of FASB flowers, the levels of minerals and vitamins, and also, evaluates the hepatoprotective effect of flowers against N-nitrosodimethylamine (NDMA) induced on liver tissue by assessing antioxidant enzymes and histopathological parameters in Wistar albino rats. Materials and methods: In the study, the rats were divided into six groups of ten. Control, untreated animals were given 0.9% NaCl. Rats were intraperitoneally given NDMA (10 mg/kg) for the first 7 days. FASB methanol extract (150 and 300 mg/kg) was administered orally for 21 days. Results: a-Tocopherol, retinol, ascorbic acid, total antioxidant activity, phenolic and flavonoid contents of FASB were 0.70 +/- 0.13, 0.29 +/- 0.03 mu g/g, 139.32 +/- 7.06 mu g/100 g, 171.61 +/- 6.05 mM ascorbic acid/g, 90.47 +/- 4.11 mg GA/g and 37.39 +/- 2.85 mg QE/g. DPPH and hydroxyl radical scavenging activity was obtained IC 50 67.34 +/- 4.14 and 64.87 +/- 4.68 mu g/mL, respectively. Discussion and conclusion: The results of the study indicated that FASB flowers contain high levels of vitamins, minerals, total antioxidant activity, phenolics and flavonoids. Due to the positive effect on significant changes in antioxidant enzymes of liver tissue and histopathological examination, it is thought that the plant could be used as a hepatoprotective.Article Fluorescence Properties and Electrochemical Behavior of Some Schiff Bases Derived From N-Aminopyrimidine(Springer/plenum Publishers, 2014) Gulcan, Mehmet; Dogru, Umit; Ozturk, Gulsiye; Levent, Abdulkadir; Akbas, EsvetA series of Schiff bases (L (1) , L (2) and L (3) ) were prepared by refluxing aromatic aldehydes with N-Aminopyrimidine derivatives in methanol and ethanol. The structures of synthesized compounds were characterized by FTIR, H-1 NMR, C-13 NMR and microanalysis. The electrochemical behaviors of the Schiff base ligands were also discussed. Moreover, the evaluation of absorption and emission properties of the structures were carried out in five different solvents. The products show visible absorption maxima in the range of 304-576 nm, and emission maxima from 636 to 736 nm in all solvents tested.Article A Green Protocol for Simple One-Pot Synthesis of New Pyrimidine Derivatives Both Microwave Irradiation and Conventional Heating: Reactions, Characterization, and Theoretical Calculations(Wiley, 2019) Akbas, Esvet; Ruzgar, Adem; Sahin, Ertan; Ergan, ErdemIn this research, 5-benzoyl-6-phenyl-4-(4-trifluoromethylphenyl)-2-{oxo and thioxo}-3,4-dihydro-1H-pyrimidines (1, 2) were synthesized by using multicomponent cyclocondensation reaction under microwave irradiation and classical heating. Compounds 3, 4, 6, 7, and 8 obtained reactions of 5-benzoyl-6-phenyl-4-(4-trifluoromethylphenyl)-2-thioxo-3,4-dihydro-1H-pyrimidine (1) and acetic anhydride, diethyl 2-bromomalonate, bromoacetic acid, 3-bromopropionic acid, methyl iodide, respectively. Compound 4 was both acetylated and hydrolyzed in acetic acid to give compound 5. The structures of all compounds were determined by using spectroscopic techniques like FT-IR, H-1/C-13 NMR, and elemental analyses, and the structures of compounds 1 and 3 were analyzed by X-ray crystal analysis. In addition, the quantum chemical parameters and full geometry optimizations for all compounds were computed using density functional theory based on B3LYP and the 6-31G (d, p) basis set.Article The Inhibition Effect of Some Pyrimidine Derivatives on Austenitic Stainless Steel in Acidic Media(Elsevier Science Sa, 2011) Caliskan, Necla; Akbas, Esvet5-Benzoyl-4-(substitutedphenyl)-6-phenyl-3,4-dihydropyrimidine-2(1H)-(thio)ones (DHPMs) (I and II) were synthesized using the Biginelli three component cyclocondensation reaction of an appropriate arylaldehyde, and (thio) urea. The effect of these corrosion inhibitors on the corrosion of austenitic stainless steel in 0.5M H2SO4 has been studied by electrochemical methods using Tafel plot, linear polarization and electrochemical impedance spectroscopy at 298K. The inhibition efficiencies obtained from all the methods employed are in good agreement. The adsorption of the DHPMs onto the stainless steel surface was found to follow Langmuir and Dubinin-Radushkevich adsorption isotherm models. Negative values of Delta G(ads) in the acidic media ensured the Spontaneity Of the adsorption process. Results show DHPM I to be the best inhibitor with a mean efficiency of 91% at 2 x 10(-3) M additive concentration. (c) 2010 Elsevier B.V. All rights reserved.Article Investigation of the Adsorption of Dacarbazine (Dtic), Which Is Used as an Anticancer Drug, on Graphene Oxide by Dft Calculation Method(2023) Akbas, Esvet; Akbaş, Begüm ÇağlaBecause of its superior properties, graphene oxide (GO) has become a potential candidate for nano-bio researchers to study its use in biomedical applications. Significant efforts have been made in recent years to explore the biomedical uses of graphene-based materials in smart medicine and genetic engineering. In this study, the electronic properties of commercially available dacarbazine (DTIC) used in cancer treatment and its adsorption on GO nanocage were calculated using density functional theory (DFT). DTIC is also known as imidazole carboxamide. It is an alkylating purine analogue chemotherapy drug used to treat melanoma and Hodgkin's lymphoma. Hodgkin usually uses it in combination with vinblastine, bleomycin, and doxorubicin. It is given by injection into a vein.Article Metal-Organic Framework Mil-101 as an Efficient Heterogeneous Catalyst for Clean Synthesis of Benzothiazoles and Single Crystal X-Ray Diffraction, Quantum Chemical Studies, Electrochemical Performance, Molecular Docking and Dna Interactions(Wiley-V C H Verlag Gmbh, 2025) Akbas, Esvet; Ruzgar, Adem; Sahin, Ertan; Levent, AbdulkadirBenzothiazoles have emerged as a prominent area of research in recent years due to their broad spectrum of biological activities. These heterocyclic compounds, which contain thiazole and benzene rings in their molecular structure, exhibit a wide range of pharmacological effects, including anticancer, antimicrobial, antifungal, antiparasitic, anti-inflammatory, and antitubercular activities. In this study, benzo[d]thiazole derivatives 1 and 2 were synthesized in good yield using catalyst MIL101. The structures of these compounds were analyzed using elemental analysis, IR, 1H, 13C NMR and single crystal X-ray diffraction. The quantum chemical calculations of these compounds were performed density functional theory method, DGDZVP base set and B3LYP functions with Gaussian09W software package. The electrochemical properties of these compounds were investigated by cyclic voltammetry technique on a glassy carbon electrode. In addition, the interactions of the compounds with DNA were investigated by electrochemical, spectrophotometric and molecular docking techniques. It was observed that the chemical calculations and molecular docking results were compatible with each other.Article Methylene Blue Adsorption From Aqueous Solution by Functionalized Perlites: an Experimental and Computational Chemistry Study(desalination Publ, 2021) Sogut, Eda Gokirmak; Ergan, Erdem; Kilic, Necla Caliskan; Donmez, Hakan; Akbas, EsvetIn this study, 3-aminopropyltrimethoxy-silane (3-APTMS) and 3-mercaptopropyltrimethoxy-silane (3-MPTMS) were used to functionalize perlite in order to increase the adsorption capacity of methylene blue (MB). These materials were characterized by X-ray diffraction, X-ray fluorescence, Fourier transform infrared spectroscopy, scanning electron microscopy, and thermal (thermogravimetry/ differential thermal analysis) analyzes. The performance of perlite and functionalized derivatives was tested by adsorption of MB in a batch system under a variable pH (2-11) and initial MB concentration (10-60 mg L-1). Nonlinear and linear Langmuir, Freundlich, Dubinin-Radushkevich (D-R), and Sips adsorption equations were applied to define equilibrium isotherms. The maximum dye sorption was found to be at a pH of 11.0 (96.44% for P-A, 96.51% for P-APTMS, and 96.73% for P-MPTMS). The adsorption capacity for the dye was found to be 4.9445, 5.2014, and 5.3112 mg g(-1) for P-A, P-APTMS, and P-MPTMS, respectively, at 298 K. The adsorption kinetics was best described by the pseudo-second-order model. The obtained results confirm that amino and mercapto functional groups have positive effects on the adsorption of methylene blue by the adsorbents used in this work. Quantum chemical analysis supported better adsorption of methylene blue dye on amine and mercapto-functionalized perlite surfaces than the unmodified surface and the most suitable site for MB adsorption was suggested by Fukui function analysis.Article Microwave-Assisted Studies on the Reactions of the 4-Benzoyl and Derivatives(Bentham Science Publ Ltd, 2010) Akbas, Esvet; Sener, AhmetVarieties of heterocyclic compounds were prepared in good yield from 4-benzoyl-5-phenyl-2,3-dihydro-2,3-furandione under microwave irradiation conditions. The reaction revealed much shorter reaction times with comparable yields comparison to the corresponding thermal conditions.Article Microwave-Assisted Synthesis of New Dihydropyrimidine Derivatives and Mechanism of the Reactions(Bentham Science Publ Ltd, 2013) Akbas, Esvet; Sahin, Ertan; Yildiz, Ela; Anil, Baris; Akyazi, Inci5-benzoyl-4-aryl-6-phenyl-1,2,3,4-tetrahydro-2-thioxopyrimidines were synthesized via Biginelli cyclocondensation reaction. The diethyl 2-(4-aryl-5-benzoyl-6-phenyl-3,4-dihydropyrimidin-2(1H)-ylidene) malonates were prepared by the reaction of thioxopyrimidines with diethyl 2-bromomalonate in dioxane/pyridine (10/1 v:v) under microwave irradiation and conventional conditions. The reaction of diethyl 2-(5-benzoyl-4,6-phenyl-3,4-dihydropyrimidin-2(1H)ylidene) malonate with hydrazine hydrate and urea yielded the compounds of (E)-ethyl 2-(5-benzoyl-4,6-diphenyl-3,4-dihydropyrimidin-2(1H)-ylidene)-3-hydrazinyl-3-oxopropanoate and (E)-ethyl 2-(5-benzoyl-4,6-diphenyl-3,4dihydropyrimidin-2(1H)-ylidene)-3-oxo-3-ureidopropanoate, respectively. All of these new derivatives were characterized by analytical and spectroscopic studies. The structure of the diethyl 2-(5-benzoyl-4,6-diphenyl-3,4-dihydropyrimidin-2(1H)-lidene) malonate was identified by a single crystal X-ray diffraction analysis, and the reaction mechanism was also discussed.Article Microwave-Assisted Synthesis of Tetrahydropyrimidines Via Multicomponent Reactions and Evaluation of Biological Activities(Bentham Science Publ Ltd, 2011) Akbas, Esvet; Berber, Ismet; Akyazi, Inci; Anil, Baris; Yildiz, ElaVarious pyrimidine derivatives (1a-c) were synthesized using the Biginelli three component cyclocondensation reactions of a beta-diketone, arylaldehyde, and thiourea, under microwave irradiation and conventional conditions. The acetylation of compound 1a gave 3-acetyl thioxopyrimidin 2. Also, thiazolopyrimidine (3) and (4) derivatives were obtained by a simple one-pot condensation reaction of starting compounds 1a, and 1b with 2-bromopropionic acid. The prepared compounds were screened for their antimicrobial activities against Gram-positive, Gram-negative bacteria and fungi using micro dilution procedure. The results of the study showed that the compound 4 was effective and selective for antimicrobial activity against the tested bacteria and fungi. Thus, we suggested that the compound 4 might be a new potential antimicrobial substance for bacteria and fungi.Article Reactions of Substituted Furan-2,3 With C- and N-Nucleophiles(Asian Journal of Chemistry, 2007) Akbas, Esvet; Daskapan, Tahir; Sener, AhmetThe thermolysis of 5-phenyl-2,3-dillydrofuran-2,3-dione in 4-methoxyphenylacetone yield 2-(4-methoxybenzyl)-2-methyl-6-phenyl-4H-1,3-dioxin-4-one via alpha-oxoketene. Reaction of 5-phenyl-2,3-dihydrofuran-2,3-dione with phenylhydrazine afforded 1,6-diphenyl-1,2-dihydropyridazine-3,4-dione. The hydrazine derivatives and 1,2-phenylenedi-. amine react with 4,4-dimethyltetrahydrofuran-2,3-dione to give the corresponding hydrazone derivatives and 3,3dimethyl-2,3-dihydrofuro[2,3-b]quinoxaline, respectively. The structures of compounds were characterized on the basis of elemental analyses, Mass, IR, H-1 and C-13 NMR spectra.Article A Simple One-Pot Synthesis of 1,2,3,4-Tetrahydro Derivatives(Wiley, 2008) Akbas, Esvet; Aslanoglu, Furgan; Anil, Baris; Sener, Ahmet5-Benzoyl-4-(substituted phenyl)-6-phenyl-1,2,3,4-tetrahydro-2-thioxopyrimidines (4a-d) were synthesized using the Biginelli three component cyclocondensation reaction of an appropriate beta-diketone, arylaldehyde, and thiourea in acetic acid under reflux condition in approximately 52-65% yields. The acetylation of compounds 4a-d gave 3-acetyl thioxopyrimidine derivatives 5a-d. Also, pyrimidothiazine compounds 6a-d were prepared by a simple one-pot condensation reaction of starting pyrimidine derivatives 4a-d and 3-bromopropionic acid. The structures of compounds were characterized on the basis of elemental analyses, IR,H-1 and C-13-NMR spectra.Article Studies on Reactions of Pyrimidine Compounds(Taylor & Francis Ltd, 2007) Aslanoglu, Furgan; Akbas, Esvet; Soenmez, Mehmet; Anil, BarisThe 5-benzoyl-4,6-diphenyl-1,2,3,4-tetrahydro-2-thioxopyrimidin (1) have been prepared via Biginelli cyclocondensation reaction in acetic acid under reflux condition in good yield (93%). Reactions of 1 and iodomethane to afford thiopyrimidine compounds 3 and 5. Also, the acetylation of compounds 1 and 3 gave 3-acetyl thioxopyrimidine 2 and methylthiopyrimidine 4, respectively. Thioxopyrimidine derivative 6 was synthesized from 1 and POCl3/DMF Furthermore, the starting compound 1 were cyclized with various bromo compounds to the thiazolopyrimidine 7, 8, 9 and pyrimido[2,3-b]thiazine10 derivatives, in approximately 55-78% yields. The purpose of synthesizing the thioxopyrimidine derivatives is because of the high biological activities. All of these derivatives have been characterized by analytical and spectroscopic studies and the reaction mechanism is discussed.Article Synthesis and Biological Evaluation of Novel Benzylidene Thiazolo Pyrimidin-3(5h) Derivatives(Taylor & Francis Ltd, 2024) Akbas, Esvet; Othman, Khdir A.; Celikezen, Fatih Caglar; Ejder, Nebahat Aydogan; Turkez, Hasan; Yapca, Omer Erkan; Mardinoglu, AdilStarting compound 1 was synthesized according to reference.(1) Benzylidene thiazole pyrimidin-3(5H)-ones were synthesized reactions of 1 with bromoacetic acid and various aryl-aldehydes in the same vessel via one-step, unlike studies in the literature. Quantum chemical parameters and full geometry optimizations for all compounds were computed using DFT based on B3LYP. Cytotoxic action potential of synthesized compounds was evaluated using trypan blue dye exclusion and MTT assays in different cell lines including adenocarcinoma alveolar basal epithelial-like adherent A549 cells, the colon adenocarcinoma HT-29 cells, prostate adenocarcinoma DU-145 cells, and diploid ARPE-19 retinal pigment epithelial cells. Embryotoxicity and genotoxicity assessments were performed on pluripotent human embryonal carcinoma NT2 and human lymphocyte cells, respectively. Compound A1 exhibited good anticancer activity on A549 and DU-145 cell lines, and the compounds including A3, 4, 6, and 9 induced cytotoxicity on A549 cells. The compounds A1-10 also showed a good biosafety profile at relatively lower concentrations.Article Synthesis of Some Novel Pyrimidine Derivatives and Investigation of Their Electrochemical Behavior(Wiley-v C H verlag Gmbh, 2010) Akbas, Esvet; Levent, Abdulkadir; Gumus, Selcuk; Sumer, Mehmet Rauf; Akyazi, Inci2-Iminopyrimidines (1a-e) and 2-thioxopyrimidine (2) were synthesized using the Biginelli three component cyclocondensation reaction of an appropriate beta-diketone, arylaldehyde, and guanidine (for 1a-e) or thiourea (for 2). The electrochemical properties of the novel systems were investigated by CV and DPV. Moreover, B3LYP/6-31G(d,p) method was applied to the present structures in order to gather some structural and physicochemical data.Article Synthesis of Some Transition Metal Complexes of Ligands Derived From 5-Phenyl(Science Reviews 2000 Ltd, 2008) Akbas, Esvet; Sonmez, Mehmet; Celebi, Metin; Aslanoglu, FurganA series of amide ligands was prepared by the reactions of 5-phenyl-2,3-dihydro-2,3-furandione and aromatic amines. The ligands reacted with Cu(II) and Ni(II) ions to yield mononuclear complexes. The ligands and complexes were characterised by elemental analyses, mass, FTIR, UV-vis, (1)H NMR and (13)C NMR spectral studies, as well as magnetic moment, AAS and conductance measurements as appropriate.Article Synthesis of the 3,5-Diphenyl and Cytogenetic and Oxidative Alterations After Exposure of Cultured Human Whole Blood Cells(Taylor & Francis As, 2017) Akbas, Esvet; Celikezen, Fatih Caglar; Turkez, Hasan; Ozdemir, Ozlem; Ruzgar, Adem; Ergan, Erdem; Sahin, ErtanThe 3,5-diphenyl-1H-pyrazole was obtained by condensation reaction of dibenzoylmethane and thiosemicarbazide in acetic acid under conventional heating and microwave irradiation method. The structure of the 3,5-diphenyl-1H-pyrazole confirmed by IR, H-1, and C-13 NMR and X-ray diffraction and the geometry optimization was carried out using density functional theory (DFT) methods at B3LYP/6-31G, 6-31G(d), 6-31G(d, p), 6-311G(d, p), 6-311G(2d, 2p), 6-31+G(d, p), 6-311++G(d, p) levels. In addition, cytotoxic and oxidative effects were investigated in cultured human peripheral blood cells.Article Synthesis, Characterization and Theoretical Studies of Novel Pyrimidine Derivatives as Potential Corrosion Inhibitors(Serbian Chemical Soc, 2020) Akbas, Esvet; Yildiz, Ela; Erdogan, AhmetIn this study, five new pyrimidine derivatives were synthesized and characterized by characterization methods such as H-1-NMR, C-13-NMR, FT-IR and elemental analysis. The corrosion inhibition activity of the synthesized compounds was examined by theoretical calculation using DFT method at the level of B3LYP/6-31G (d,p). According to the calculations, 4-(6-benzoyl-2-benzylidene-3-oxo-7-phenyl-2,3-dihydro-5H-thiazolo[3,2-a]pyrimidin-5-yl)-benzoic acid (6) appears to be a good inhibitor for corrosion.Article Synthesis, Characterization, Quantum Chemical Studies and Electrochemical Performance of New 4,7-Dihydrotetrazolo[1,5 Derivatives(indian Acad Sciences, 2019) Akbas, Esvet; Celik, Savas; Ergan, Erdem; Levent, AbdulkadirIn this study, 4,7-dihydrotetrazolo[1,5-a]pyrimidine derivatives (1-5) were prepared via Multicomponent Cyclocondensation Reactions (MCRs). All structures were determined by using FT-IR, 1H/13C NMR and elemental analyses. The compounds were investigated as corrosion inhibitors using density functional theory (DFT) at the level of B3LYP/6-31G (d, p). According to the calculations, compound 1 appears to be a good inhibitor for corrosion. In addition, the electrochemical properties of the novel systems were investigated by CV.Graphical Abstract:The synthesis, characterization, quantum chemical studies and electrochemical performance of new 4,7-dihydrotetrazolo[1,5-a]pyrimidine derivatives are reported.