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Öğe (2,6-bis{1-[4-(dimethylamino)phenylimino]ethyl}pyridine)dichlorido(tri-phenylphosphine-?P)ruthenium(II): a zigzag chain of fused centrosymmetric R22(12) rings(Int Union Crystallography, 2007) Ozdemir, Namik; Dincer, Muharrem; Dayan, Osman; Cetinkaya, BekirThe title compound, [RuCl2(C25H29N5)(C18H15P)], a transfer hydrogenation catalyst, is supported by an N,N',N-tridentate pyridine-bridged ligand and triphenylphosphine. The Run centre is six-coordinated in a distorted octahedral arrangement, with the two Cl atoms located in the axial positions, and the pyridine (py) N atom, the two imino N atoms and the triphenylphosphine P atom located in the equatorial plane. The two equatorial Ru-N-imino distances (mean 2.093 angstrom) are substantially longer than the equatorial Ru-N-py bond [1.954 (4) angstrom]. It is observed that the N-imino-M-N-py bond angle for the five-membered chelate rings of 2,6-bis(imino)pyridine-based complexes is inversely related to the magnitude of the M-N-py bond. The title structure is stabilized by intra- and intermolecular C-H... Cl hydrogen bonds, as well as by intramolecular pi-pi stacking interactions between the aromatic rings belonging to the triphenylphosphine ligand and the dimethylaminophenyl fragment. The intermolecular 2 hydrogen bonds form an R-2(2)(12) ring and a zigzag chain of fused centrosymmetric rings running parallel to the [100] direction.Öğe (2Z,6Z)-N2,N2?-bis(2,6-diisopropylphenyl)-N1,N1?-bis(2-methoxyethyl)pyridine-2,6-dicarboxamidine(Int Union Crystallography, 2008) Dincer, Muharrem; Ozdemir, Namik; Dayan, Osman; Cetinkaya, BekirIn the title compound, C37H53N5O2, the benzene rings make dihedral angles of 84.61 (8) and 67.10 (9)degrees with the pyridine ring. The crystal structure is stabilized by strong intramolecular interactions. The two (2-methoxyethyl) amine groups are disordered over two positions; the site occupancies are ca 0.6 and 0.4.Öğe A hydrazine-bridged dinuclear ruthenium complex: Structural properties and biological activity(Elsevier, 2023) Erdener, Digdem; Dervisoglu, Gokhan; Ozdemir, Fethi Ahmet; Serbetci, Zafer; Ozdemir, Namik; Dayan, OsmanIn this study, a new dimeric Ru(II) complex, [Ru(eta(6)-p-cymene)Cl-2](2) (mu(2)-N-2 H-4) (C1), readily synthesized with a reaction of hydrazine hydrate as ligand and [RuCl2(p-cymene)](2) dimmer in dichloromethane. The C1 complex was characterized structurally using IR, NMR, thermal gravimetry and single-crystal X-ray diffraction and theoretically using DFT techniques. Additionally, electrochemical, and optical properties were investigated in cyclic voltammetry and UV-visible spectroscopy. Furthermore, the C1 complex exhibited great antibacterial activity towards 16 Gram + and Gram - species and cell cytotoxicity towards human SH-SY5Y neuroblastoma cell, DU-145 prostate cancer cell, and A549 lung cancer cell lines. (c) 2022 Elsevier B.V. All rights reserved.Öğe A light-detecting Ru(II)/Si heterojunction system involving a binuclear Ru (II) complex with pyridine-2,6-diimine (pydim) ligand(Springer, 2024) Koc, Muemin Mehmet; Dayan, Osman; Dere, Aysegul; Cetinkaya, Bekir; Coskun, Burhan; Yakuphanoglu, FahrettinA meticulously detailed chemical procedure was employed to synthesize the Ru (II)-containing pyridine-2,6-diimine (pydim) organometallic complex. The resulting complex was then applied to Al-coated Si wafers using the spin-coating technique, leading to the production of Al/Ru(II) organometallic complex/n-Si/Al photodiodes. The light responsiveness of these photodiodes was demonstrated through the acquisition of I-V and I-t characteristics. Subsequently, essential parameters such as ideality factor, photosensitivity, barrier height, and photoresponse values were evaluated based on the obtained I-V and I-t plots. The calculations yielded ideality factors and barrier heights, resulting in average values of 6.41 and 0.552 eV, respectively. Furthermore, an in-depth analysis of the electrical properties of the diodes was conducted using G-V and C-V assessments, revealing a strong dependence on AC signal frequency. This investigation underscored that the observed frequency-related electrical behaviour is rooted in series resistance and interface states.Öğe A neutral arene ruthenium(II) complex with a sulfonated N,O-chelating ligand: Synthesis, characterization, in vitro cytotoxicity and antibacterial activity(Pergamon-Elsevier Science Ltd, 2020) Selvi, Gizem; Ozdemir, Fethi Ahmet; Aykutoglu, Gurkan; Ozdemir, Namik; Serbetci, Zafer; Cetinkaya, Bekir; Dayan, OsmanIn this work, a new N,O-type ligand (L1H) containing a sulfonate ester group and its heteroleptic Ru(II) complex (C1) have been prepared and structurally characterized by various techniques, such as UV-vis, ESI-MS, NMR and IR. The spectroscopic results (IR, UV-vis and NMR) were compared with the results of density functional theory (DFT) calculations. The solid-state structures of L1H and C1 were crystallographically verified. Moreover, the in vitro cytotoxicity and antibacterial properties of 1, L1H and Cl have been screened. All the compounds exhibited good cytotoxicity towards human neuroblastoma cancer cells and antibacterial effects towards 16 bacterial strains, both gram positive and negative. The results revealed that the Ru(II) complex exhibits higher biological activities than the starting materials 1 and L1H. (C) 2019 Elsevier Ltd. All rights reserved.Öğe A new phosphazene derivative, spiro-N3P3[(O2C12H8)2(OC6H6N-3)2], and its Ru(II) complex: Syntheses, crystal structure, catalytic activity and antimicrobial activity studies(Pergamon-Elsevier Science Ltd, 2015) Cirali, Digdem Erdener; Dayan, Osman; Ozdemir, Namik; Hacloglu, NurcihanA cyclotriphosphazene ligand containing the spirocyclic 2,2'-dioxybiphenyl group and 2-methy1-3-pyridyloxy moieties was synthesized. A Ru(11) complex was prepared from the reaction of [RuCl2(p-cymene)](2) with this ligand. The structures of the ligand and the Ru(II) complex were characterized by FT-IR, H-1 and P-31 NMR spectroscopy. In addition, the molecular structure of the ligand was confirmed by X-ray crystallography. The Ru(II) complex was used as catalyst for the Catalytic Transfer Hydrogenation (CTH) of p-substituent acetophenone derivatives in the presence of KOH. The antimicrobial activities of the ligand and the complex have also been studied. The antimicrobial activities have been screened in vitro against Gram-positive (Staphylococcus aureus ATCC 6538, Bacillus cereus ATCC 7064, Listeria monocytogenes ATCC 15313, Micrococcus luteus La 2971) and Gram-negative (Escherichia coil ATCC 11230, Klebsiella pneumoniae UC57, Pseudomonas aeruginosa ATCC 27853, Proteus vulgaris ATCC 8427, Enterobacter aerogenes ATCC 13048) bacteria and yeast cultures (Candida albi cans ATCC 10231, Kluyveromyces fragills NRRL 2415, Rhodotorula rubra DSM 70403) using both the disk diffusion and dilution methods. (C) 2015 Elsevier Ltd. All rights reserved.Öğe (Acetonitrile){2,6-bis[1-(2,4,6-trimethylphenylimino)ethyl]pyridine} dichloridoruthenium(II) dichloromethane solvate(Int Union Crystallography, 2007) Ozdemir, Namik; Dincer, Muharrem; Dayan, Osman; Cetinkaya, BekirIn the title compound, [RuCl2(C2H3N)(C27H31N3)] center dot CH2Cl2, the Ru-II ion is six-coordinated in a distorted octahedral arrangement, with the two Cl atoms located in the apical positions, and the pyridine (py) N atom, the two imino N atoms and the acetonitrile N atom located in the basal plane. The two equatorial Ru - N-imino distances are almost equal ( mean 2.087 angstrom) and are substantially longer than the equatorial Ru - N-py bond [1.921 ( 4) angstrom]. It is observed that the N-imino-M-N-py angle for the five-membered chelate rings of pyridine-2,6-diimine complexes is inversely related to the magnitude of the M-N-py bond. The title structure is stabilized by intra- and intermolecular C-H center dot center dot center dot Cl hydrogen bonds, as well as by van der Waals interactions.Öğe Antioxidant Activity of Ruthenium(Ii) Complexes Containing Tridentate Triamines and Their Capability to Inhibit Xanthine Oxidase(Springer, 2020) Gecibesler, Ibrahim H.; Dayan, Osman; Serbetci, Zafer; Demirtas, IbrahimBiological activities of organoruthenium complexes [chloro [N,N '-[(2,6-pyridinediyl-kappa N) diethylidyne] bis-[benzenamine-kappa N]] [N-[(2-pyridinyl-kappa N) methylene] benzenesulfonamide-kappa N] ruthenium(II)] chloride (Cmplx 1), [chloro [2,2 '-(2,6-pyridinediyl-kappa N) bis [1H-benzimidazole-kappa N-3]][N-[(2-pyridinyl-kappa N) methylene] benzenesulfonamide-kappa N] ruthenium(II)] chloride (Cmplx 2), and [chloro[2,6-di(1H-pyrazol-3-yl-kappa N-2) pyridine-kappa N] [N-[(2-pyridinyl-kappa N) methylene] [benzenesulfonamide-kappa N] ruthenium(II)] chloride (Cmplx 3) have been studies. The compounds were tested for in vitro biological activity on test models including 2,2-diphenyl-1-picryl-hydrazyl (DPPH) reducing power, superoxide anion radical-scavenging activity, and lipid peroxidation activity by ferric thiocyanate. It is established that Cmplx 2 with benzimidazole ligand displays significant xanthine oxidase inhibitory activity (IC50 = 53.80 +/- 2.69 mu M), DPPH free radical scavenging activity (79.49 +/- 1.59), and superoxide anion radical scavenging activity (75.73 +/- 2.85%). The coordination of benzenamine and benzenesulfanoamine ligands reduces lipid peroxidation as observed in the case of Cmplx 1 (87.17 +/- 3.88%) and the higher reducing power of Cmplx 1 obtained at all concentrations. It was concluded from the test results that organoruthenium complexes showed much better antioxidant activity than expected.Öğe Bis{2,6-bis[1-(4-fluorophenylimino)ethyl]pyridine}-1?3N,N?,N;3?3N,N?,N-di-?-chlorido-1:2?2Cl:Cl;-2:3?2Cl:Cl-trichlorido-1?Cl,2?Cl,3?Cl-2-copper(I)-1,3-dicopper(II)(Int Union Crystallography, 2008) Ozdemir, Namik; Dincer, Muharrem; Dayan, Osman; Cetinkaya, BekirThe title complex, [Cu3Cl5(C21H17N3F2)(2)], is the first reported copper trimer including both Cu-I and Cu-II ions. The two Cu-II ions are five-coordinate in a significantly distorted square-pyramidal arrangement, with the bridging Cl atom located in the apical position, and the pyridine (py) N atom, the two imine N atoms and the other Cl atom located in the basal plane. The Cu-I ion is in a trigonal planar configuration surrounded by three Cl atoms. The structure is stabilized by intra- and intermolecular C-H center dot center dot center dot Cl and C-H center dot center dot center dot pi(py) hydrogen bonds.Öğe Catalytic and biological activities of homoleptic palladium(II) complexes bearing the 2-aminobenzothiazole moiety(Elsevier, 2021) Dayan, Serkan; Tercan, Melek; Özdemir, Fethi Ahmet; Aykutoğlu, Gürkan; Özdemir, Namık; Şerbetçi, Zafer; Dinçer, Muharrem; Dayan, OsmanThe palladium(II) complexes PdL1-3, bearing bi-dentated Schiff base ligands (L1-3) were synthesized and characterized by FT-IR, NMR and single crystal-XRD techniques, and the structural, spectroscopic and electronic properties were obtained using the B3LYP density functional method (DFT). The fabricated complexes were used as catalysts in the reduction of some organic pollutants (4-nitrophenol (4-NP), Rhodamine B (Rh B) and methylene blue (MB)) in water at an ambient temperature. The PdL3 complex was recorded as the best catalyst compared to the other complexes and the highest conversion rates were in the order of MB > RhB > 4-NP. Also, the antimicrobial and antifungal activities of all the compounds (ligands and complexes) and the cytotoxic effects on DU-145 and SH-SY5Y cells were investigated. The PdL1-3 complexes show cytotoxic effects, especially against the SH-SY5Y cells. All the synthesized com- pounds showed moderate antimicrobial and antifungal properties.Öğe Catalytic and biological properties of palladium(II) complexes with bidentate Schiff base ligands(John Wiley and Sons Ltd, 2023) Dervişoğlu, Gökhan; Özdemir, Fethi Ahmet; Özdemir, Namık; Şerbetçi, Zafer; Dayan, Osman; Kaya Özgür, GizemIn this study, we synthesized and characterized Schiff base ligands (S1–3), which contained sulfonamide/sulfonate groups, and their corresponding Pd(II) complexes (K1–3). We also introduced these complexes into Al2O3-supported materials (M1–3) using the impregnation method. Following the structural characterization, we proceeded to evaluate the performance of the supported materials in a series of degradation and reduction reactions of involving organic pollutants. These assessments were conducted with the intention of exploring their potential as catalysts in aqueous environments in the presence of NaBH4. The study's findings present novel approaches to develop effective catalysts for reducing/degrading organic pollutants in aqueous environments. The M2 catalyst showed excellent results for dye mixing after 90 s. Additionally, we investigated the antibacterial and cytotoxic properties of the synthesized compounds. The outcome also suggests that these synthesized compounds exhibit potential antibacterial and cytotoxic properties.Öğe Concomitant polymorphism of a pyridine-2,6-dicarboxamide derivative in a single space group: Experimental and molecular modeling study(Pergamon-Elsevier Science Ltd, 2012) Ozdemir, Namik; Dayan, Osman; Cetinkaya, Bekir; Akgul, CahitThe title compound, N-2,N-6-bis{2-[(Z)-2-hydroxybenzylideneamino]phenyl}pyridine-2,6-dicarboxamide (3), has been synthesized by the reaction of 2-{(2-aminophenylimino)methyl}phenol (1) with pyridine2,6-dicarbonyl dichloride (2), and characterized by elemental analysis. FT-IR and NMR spectroscopies and thermal analysis. Compounds 1 and 3 were evaluated for their antibacterial activities against Grampositive and Gram-negative bacteria. The catalytic activity of 3 was also studied, and as a result, the in situ prepared three component system Ru(II)/3/KOH is shown to be an efficient catalyst for the transfer hydrogenation reaction of various ketones under mild conditions. Compound 3 has been crystallized in two polymorphic forms under the same conditions, and their crystal structures have been determined using single crystal X-ray diffraction technique. The molecular geometry, vibrational frequencies and gauge-independent atomic orbital (CIAO) H-1 and C-13 NMR chemical shift values of 3 in the ground state have been calculated using the density functional theory (DFT/B3LYP) method with the 6-31G(d) basis set, and compared with the experimental data. The results are in good agreement with experimental data. The effect of different solvents on the geometry, vibrational frequencies, total energies and dipole moments was also studied using the same method by applying the Onsager Model. There are subtle differences in the conformations and packing of the two polymorphs as a consequence of intermolecular hydrogen bonding interactions. Therefore, DFT calculations for the hydrogen bond interactions in the polymorphs were carried out using same basis set. The changes of thermodynamic properties from the monomers to 3 with the temperature ranging from 200 K to 400 K have been obtained using the statistical thermodynamic method. (C) 2011 Elsevier B.V. All rights reserved.Öğe Direct and solvent-assisted thione-thiol tautomerism in 5-(thiophen-2-yl)-1,3,4-oxadiazole-2(3H)-thione: Experimental and molecular modeling study(Elsevier, 2014) Arslan, N. Burcu; Ozdemir, Namik; Dayan, Osman; Dege, Necmi; Koparir, Metin; Koparir, Pelin; Muglu, HalitThe compound has been synthesized and characterized by IR, NMR and X-ray diffraction. Quantum chemical calculations at B3LYP/6-311++G(d,p) level were performed to study the molecular and spectroscopic properties, conformational equilibrium, thione <-> thiol tautomerism and intermolecular double proton transfer reaction of the compound. The obtained structural and spectroscopic results are well in agreement with the experimental data. The solvent effect on the proton transfer reaction was investigated in three solvents using the polarizable continuum model approximation and solvent-assisted mechanism. The anti-thione tautomer is the most stable isomer among the four possible structural forms both in the gas phase and in solution phase. A high tautomeric energy barrier is found for the tautomerism between the anti and syn forms of the compound, indicating a quite disfavored process. Although the presence of one methanol or water solvent molecule significantly lowers the energy barrier, it is not adequate for the reaction to occur. (C) 2014 Elsevier B.V. All rights reserved.Öğe Dye sensitized solar cell-based optoelectronic device using novel [Ru(L1)(L2)(NCS)2] complex(Elsevier B.V., 2021) Dayan, Osman; Gençer İmer, Arife; Tercan, Melek; Dere, Ayşegül; Al-Sehemi, Abdullah G.; Al-Ghamdi, Ahmed A.; Yakuphanoğlu, FahrettinA dye sensitized solar cell-based photodiode was prepared using novel [Ru(L1)(L2)(NCS)2] complex for solar energy and optoelectronic applications. The new heteroleptic ruthenium(II) complex [Ru(L1)(L2)(NCS)2], was synthesized from the reaction of (pyridyl)benzimidazole ligands. The possible usage of [Ru(L1)(L2)(NCS)2] complex in dye synthesized solar cell-based photodiode was investigated using electrical and capacitance characteristics. The device was irradiated under various solar light intensities. The change in photocurrent of the device confirms the photoconducting behavior of prepared device. The device exhibited both the photocapacitance and photoresponse behavior with solar illumination. The obtained optoelectrical results suggest that the studied photodiode with [Ru(L1)(L2)(NCS)2] complex could be used in optoelectronic device for optical switching and controlling applications.Öğe Enol-imine/keto-amine tautomerism of (E)-4-[(2-hydroxybenzylidene)amino]phenyl benzenesulfonate(Int Union Crystallography, 2016) Dincer, Muharrem; Ozdemir, Namik; Kagit, Reyhan; Dayan, Osman[Anstract Not Available]Öğe Experimental and molecular modeling investigation of (E)-N-{2-[(2-hydroxybenzylidene)amino]phenyl}benzenesulfonamide(Taylor & Francis Ltd, 2013) Ozdemir, Namik; Dayan, Serkan; Dayan, Osman; Dincer, Muharrem; Kalaycioglu, Nilgun O.The Schiff base compound (E)-N-{2-[(2-hydroxybenzylidene)amino]phenyl}benzenesulfonamide has been synthesized and characterized by IR, NMR and Uv-vis spectroscopies, and single-crystal X-ray diffraction technique. In addition, quantum chemical calculations employing density functional theory (DFT) method with the 6311++G(d,p) basis set were performed to study the molecular, spectroscopic and some electronic structure properties of the title compound, and the results were compared with the experimental findings. There exists a good correlation between experimental and theoretical data. Enol-imine/keto-amine tautomerization mechanism was investigated in the gas phase and in solution phase using the polarizable continuum model (PCM) approximation. The energetic and thermodynamic parameters of the enol-imineketo-amine transfer process show that the single proton exchange is thermodynamically unfavored both in the gas phase and in solution phase. However, the reverse reaction seems to be feasible with a low barrier height and is supported by negative values in enthalpy and free energy changes both in the gas phase and in solution phase. The solvent effect is found to be sizable with increasing polarity of the solvents for the reverse reaction. The predicted nonlinear optical properties of the compound are found to be much greater than those of urea.Öğe Half-Sandwich Ru(II) Complexes Bearing 2-(2¢-quinoly)benzimidazoles with Anticancer Activity(AMG Transcend Association, 2024) Erdem, Ahmet; Mutlu, Dogukan; Kilincarslan, Rafet; Dayan, Osman; Arslan, SevkiIn this article, cytotoxic and apoptotic properties of previously synthesized and characterized four different half?sandwich ruthenium (II) complexes (C1-C4) with 2-(2¢-quinoly) benzimidazole frameworks (L1-L5) were described. These Ru (II) complexes (C1-C4) had strong cytotoxic activity towards the human glioblastoma (U373) cancer cell line with low toxicity to the non-cancerous human embryonic kidney (HEK293) cell line. Mechanistic studies revealed that all complexes caused apoptosis induction by activating caspases with upregulation of Bax and downregulation of Bcl-2. Our results indicate that ruthenium (II) complexes with 2-(2¢-quinoly) benzimidazole frameworks, especially C1 and C4, had a higher cytotoxic and apoptotic activity in human glioblastoma cells, and they should be further evaluated in detail for its anticancer properties as a new therapeutical strategy for glioblastoma. © 2024 by the authors.Öğe Heteroleptic ruthenium(II) complexes of 2-(2-pyridyl)benzimidazoles: A study of catalytic efficiency towards transfer hydrogenation of acetophenone(Pergamon-Elsevier Science Ltd, 2015) Dayan, Osman; Demirmen, Selin; Ozdemir, NamikSix ruthenium(II) complexes ([RuCl2(p-cymene)(L1-6)], SD1-6, (L1-6: bidentate pyridyl-benzimidazole ligands)) were synthesized from [RuCl2(p-cymene)](2) dimer and bidentate pyridyl-benzimidazole ligands. The compounds were characterized by elemental analysis, IR, UV-Vis, NMR and X-ray diffraction. The synthesized Ru(II) complexes (SDI-6) were tested as catalysts for the catalytic transfer hydrogenation (CH) of acetophenone to secondary alcohols in the presence of KOH using 2-propanol as a hydrogen source at 82 degrees C. All complexes were active catalysts for TM of acetophenone with good yields under mild conditions (after 15 min, yields of up to 91%). (C) 2014 Elsevier Ltd. All rights reserved.Öğe Investigation of enol-imine/keto-amine tautomerism in (E)-4-[(2-hydroxybenzylidene)amino]phenyl benzenesulphonate by experimental and molecular modelling methods(Taylor & Francis Ltd, 2016) Ozdemir, Namik; Kagit, Reyhan; Dayan, OsmanThe Schiff base compound (E)-4-[(2-hydroxybenzylidene)amino]phenyl benzenesulphonate has been synthesised from the reaction of 4-aminophenyl benzenesulphonate and salicylaldehyde, and characterised by spectroscopic and single-crystal X-ray diffraction techniques. Quantum chemical calculations employing density functional theory method with the 6-311++G(d,p) basis set were performed to study the molecular, spectroscopic and enol-imine/keto-amine tautomerisation mechanism of the title compound. An acceptable correlation between experimental and theoretical findings is obtained. Enol-imine/keto-amine tautomerisation mechanism was investigated in the gas phase and in solution phase using the polarisable continuum model approximation. The energetic and thermodynamic parameters of the enol-imine -> keto-amine transfer process show that the single proton exchange is unfavoured in all cases. Contrarily, the reverse reaction seems to be feasible with a very low barrier height and is supported by negative values in enthalpy and free energy changes for all cases.Öğe Investigation of the effect of alkyl substitution on DSSC efficiency of Ru(II) complexes bearing tridentate benzimidazole ligands(Taylor & Francis Inc, 2020) Tercan, Melek; Dayan, OsmanIn this study, tridentate 2,6-bis(5,6-dimethyl-1H-benzimidazol-2-yl)pyridine ligand (L1) and eight derivatives (L2-9) were prepared by substitution with alkyl chains and Ru(II) complexes of these ligands (C1-9) were synthesized. The synthesized ligands and their Ru(II) complexes were characterized by FTIR, UV-vis, H-1-NMR, and ESI/MS spectroscopic methods. The absorption and the emission spectra of the complexes were examined, HOMO-LUMO energy levels of the complexes were determined by cyclic voltammetry and their use as photosensitizer in dye-sensitized solar cells (DSSCs) was investigated. The effects of alkyl chain substitution on absorption in the visible region and on the current-potential characteristics of the complexes are discussed. The effects of this modification on the important parameters for DSSCs such as absorption, current density were examined and power conversion efficiency values of the Ru(II) complexes are reported.
