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Öğe 1,3-Bis(2-thienylmethyl)-4,5-dihydroimidazolium trichlorido(?6-p-cymene) ruthenate(II)(Int Union Crystallography, 2009) Arslan, Hakan; VanDerveer, Don; Ozdemir, Ismail; Gurbuz, Nevin; Gok, Yetkin; Cetinkaya, BekirThe asymmetric unit of the title compound, (C13H15N2S2)-[RuCl3(C10H14)], contains a 1,3-(2-thienylmethyl)-4,5-dihydroimidazolium cation and a trichlorido(eta(6)-p-cymene)ruthenate(II) anion. The thiophene rings of the cation are disordered by an 180 degrees rotation about the thiophene-CH2 bonds with occupancies of 0.847 (5)/0.153 (5) and 0.700 (5)/0.300 (5), respectively. The Ru atom exhibits a distorted octahedral coordination with the benzene ring of the p-cymene ligand formally occupying three sites and three Cl atoms occupying the other three sites. The short C-N bond lengths in the imidazoline ring indicate partial electron delocalization within the N-C-N fragment. Cation and anions are connected through five intermolecular C-H center dot center dot center dot Cl hydrogen bonds and one C-H center dot center dot center dot pi hydrogen bond, forming a three-dimensional hydrogen-bonded network.Öğe 1,3-Bis(4-tert-butylbenzyl)-4,5-dihydroimidazolium chloride monohydrate(Int Union Crystallography, 2009) Arslan, Hakan; VanDerveer, Don; Yasar, Sedat; Ozdemir, Ismail; Cetinkaya, BekirIn the title compound, C25H35N2+center dot Cl-center dot H2O,the imidazolidine ring adopts a twisted conformation, with a pseudo-twofold axis passing through the N-C-N carbon and the opposite C-C bond. The N-C-N fragment of the imidazolidine ring shows some degree of both double- and single-bond character due to partial electron delocalization. One of the tert-butyl groups is disordered over two conformations with occupancies of 0.714 (8) and 0.286 (8). In the crystal, O-H center dot center dot center dot Cl and C-H center dot center dot center dot O hydrogen bonds help to establish the packing.Öğe 1,3-Bis(thiophen-2-ylmethyl)-3,4,5,6-tetrahydropyrimidinium trichlorido(?6-p-cymene)ruthenate(II)(Wiley-Blackwell, 2009) Arslan, Hakan; VanDerveer, Don; Ozdemir, Ismail; Gurbuz, Nevin; Gok, Yetkin; Cetinkaya, BekirThe asymmetric unit of the title compound, (C14H17N2S2)-[Ru(C10H14)Cl-3], contains a 1,3-bis(thiophen-2-ylmethyl)-3,4,5,6-tetrahydropyrimidinium cation and a trichlorido(eta(6)-p-cymene) ruthenate(II) anion. The Ru atom exhibits a distorted octahedral coordination with the benzene ring of the p-cymene ligand formally occupying three sites and three chloride atoms occupying the other three sites. The N-C bond lengths of the N-C-N unit of the pyrimidinium cation are shorter than the average single C-N bond length of 1.48 angstrom, thus showing double-bond character, indicating a partial electron delocalization within the N-C-N fragment. The pyrimidine ring has an envelope conformation. Four intermolecular C-H center dot center dot center dot Cl hydrogen bonds generate a three-dimensional hydrogen-bonded framework.Öğe 1,3-Bis[4-(dimethylamino)benzyl]-4,5,6,7-tetrahydro-1H-1,3-diazepan-2-ium chloride(Wiley-Blackwell, 2009) Arslan, Hakan; VanDerveer, Don; Gok, Yetkin; Ozdemir, Ismail; Cetinkaya, BekirThe title N-heterocyclic carbene derivative, C23H33N4+center dot Cl-, has been synthesized and characterized by elemental analysis, H-1 and C-13 NMR, IR spectroscopy and a single-crystal X-ray diffraction study. Ions of the title compound are linked by three C-H center dot center dot center dot Cl interactions. The seven-membered 1,3-diazepane ring has a form intermediate between twist-chair and twist-boat.Öğe 1-(1H-Benzimidazol-1-ylmethyl)-3-[2-(diisopropylamino)ethyl]-1H-benzimidazolium bromide 0.25-hydrate(Int Union Crystallography, 2009) Arslan, Hakan; VanDerveer, Don; Demir, Serpil; Ozdemir, Ismail; Cetinkaya, BekirThe title N-heterocyclic carbene derivative, C23H30N5+center dot Br-center dot 0.25H(2)O, was synthesized using microwave heating and was characterized by H-1 and C-13 NMR spectroscopy and a single-crystal X-ray diffraction study. The structure of the title compound are stabilized by a network of intra-and intermolecular C-H center dot center dot center dot Br hydrogen-bonding interactions. The crystal structure is further stabilized by pi-pi stacking interactions between benzene and imidazole fragment rings of parallel benzo[d] imidazole rings, with a separation of 3.486 (3) angstrom between the centroids of the benzene and imidazole rings. There is also an intermolecular C-H center dot center dot center dot pi interaction in the crystal structure. The C-N bond lengths for the central benzimidazole ring are shorter than the average single C-N bond, thus showing varying degrees of double-bond character and indicating partial electron delocalization within the C-N-C-N-C fragment. The isopropyl group is disordered over two sites with occupancies of 0.792 (10) and 0.208 (10).Öğe 1-(4-tert-Butylbenzyl)-3-(3,4,5-trimethoxybenzyl)benzimidazolium bromide monohydrate(Wiley-Blackwell Publishing, Inc, 2009) Arslan, Hakan; VanDerveer, Don; Demir, Serpil; Ozdemir, Ismail; Cetinkaya, BekirA novel N-heterocyclic carbene derivative, C(28)H(33)N(2)O(3)(+)center dot-Br(-)center dot H(2)O, was synthesized and characterized by elemental analysis, (1)H and (13)C-NMR and IR spectroscopy and a single-crystal X- ray diffraction study. Ions of the title compound are linked by pi center dot center dot center dot pi stacking interactions (face-face separation 3.441 angstrom) and C-H center dot center dot center dot Br and O-H center dot center dot center dot Br interactions. Intra- and intermolecular C-H center dot center dot center dot O interactions are also present. The C-N bond lengths for the compound [1.329 (3), 1.325 (3), 1.389 (3) and 1.391 (3) angstrom] are all shorter than the average single C-N bond length of 1.48 angstrom, thus showing varying degrees of double-bond character.Öğe 2-(4-Pyridyl)-1,3-di(4-picolyl)imidazolidine(Mdpi, 2010) Yigit, Beyhan; Yigit, Murat; Ozdemir, Ismail; Cetinkaya, Bekir; Cetinkaya, EnginThe title compound was prepared by treatment of N,N'-di(4-picolyl-amino) ethane with N,N-dimethylformamide dimethylacetal in toluene and it was characterized by elemental analysis, H-1 NMR and C-13 NMR.Öğe 4,5-Dihydro-imidazol-2-ylidene-linked palladium complexes as catalysts for the direct C-H bond arylation of azoles(Wiley, 2022) Kaloglu, Murat; Ozdemir, Namik; Ozdemir, IsmailRecently, PEPPSI-type palladium-complexes bearing N-heterocyclic carbene (NHC) ligand have commonly been used as the effective catalysts in the direct arylation of heteroaromatic compounds. In most of previous studies catalyzed by such complexes, unsaturated ring carbene ligands such as benzo[d]imidazol-2-ylidene and imidazol-2-ylidene were used. However, the use of saturated ring carbene ligands such as 4,5-dihydro-imidazol-2-ylidene has been highly limited. Therefore, in this study, four novel 4,5-dihydro-1H-imidazolium salts were synthesized as saturated ring carbene precursors. Then, well-defined air- and moisture-stable four novel PEPPSI-type palladium-complexes with 4,5-dihydro-imidazol-2-ylidene ligands were prepared. All synthesized carbene precursors and palladium-complexes were structurally characterized by different spectroscopic and analytical techniques. Further structural characterization of two of the palladium-complexes was performed by single-crystal X-ray diffraction. Next, the palladium-complexes were tested in the direct arylation of azoles such as 4,5-dimethylthiazole and 1-methyl-1H-imidazole with (hetero)aryl halides in presence of 1 mol% catalyst loading at 120 degrees C. The results showed that these novel palladium complexes are effective catalysts.Öğe 5-Nitrobenzimidazole containing Pd(II) catalyzed C-C cross-coupling reactions: The effect of the N-substituent of the benzimidazole structure on catalyst activity(Elsevier Science Bv, 2019) Buldurun, Kenan; Ozdemir, IsmailA series of Pd(II) complexes (1a-e) were successfully synthesized by reaction of N-substituted 5-nitrobenzimidazole with [PdCl2(CNCH3)(2)] in toluene under argon reflux condition. Their catalytic activity in the Suzuki-Miyaura and Mizoroki-Heck coupling reactions were investigated. All these complexes were characterized by elemental analysis, H-1 NMR, C-13 NMR and IR spectroscopy. The catalytic activities of N-substituted 5-nitrobenzimidazole palladium (II) complexes were screened in Mizoroki-Heck and Suzuki-Miyaura coupling reactions. The reactions were optimized for the most suitable temperature, solvent and base system. The Pd(II) complexes exhibited good catalytic activity at the Mizoroki-Heck reaction. Additionally, the Suzuki-Miyaura showed relatively excellent activity at the coupling reaction. (C) 2019 Elsevier B.V. All rights reserved.Öğe Active ruthenium(II)-NHC complexes for alkylation of amines with alcohols using solvent-free conditions(Pergamon-Elsevier Science Ltd, 2020) Yigit, Beyhan; Karaca, Emine Ozge; Yigit, Murat; Gurbuz, Nevin; Arslan, Hakan; Ozdemir, IsmailA series of new ruthenium(II) complexes bearing N-heterocyclic carbene ligands with benzylic groups were prepared by transmetallation reactions between silver(I) N-heterocyclic carbene complexes and [RuCl2(P-cymene)](2). All of the obtained complexes were characterized by FT-IR, H-1 NMR and C-13 NMR spectroscopy, and the molecular structure of compound 3c was also determined by X-ray crystallography. These ruthenium complexes were tested for the alkylation of aromatic amines with a wide range of primary alcohols under solvent-free conditions using the hydrogen borrowing strategy. All of the compounds tested here showed excellent catalytic activity for these reactions and N-monoalkylated products were obtained selectively using 2.5 mol% of the ruthenium complexes. (C) 2019 Elsevier Ltd. All rights reserved.Öğe Activity of Benzimidazole Derivatives and their N-Heterocyclic Carbene Silver Complexes Against Leishmania major Promastigotes and Amastigotes(Amg Transcend Assoc, 2023) Khan, Tariq A.; Mnasri, Aziza; Al Nasr, Ibrahim S.; Ozdemir, Ismail; Gurbuzd, Nevin; Hamdi, Naceur; Biersack, BernhardLittle progress was conducted concerning discovering new efficient antileishmanial drugs for many years. Hence, the disease has become a global health problem meanwhile. Benzimidazole derivatives and heavy metal complexes have shown potent antiparasitic activities. The present work is intended to evaluate fourteen synthetic benzimidazolium salts and N-heterocyclic silver carbene complexes against Leishmania major. Promastigotes and amastigotes of L. major were cultured in vitro to evaluate compound-induced inhibitory effects, and isolated mouse macrophages were used for cytotoxicity evaluation. Reactive oxygen species (ROS) formation was detected for all compounds as a possible mode of action. The silver complexes 3d and 3e revealed significant activity against L. major promastigotes with IC50 values of 6.4 and 5.5 mu g mL(-1), and SI of 1.77 and 2.02, respectively. Both complexes showed higher ROS production in promastigotes than in macrophages. Further in vivo and enzyme inhibition studies are recommended to evaluate the potential of these compounds as new antileishmanial.Öğe Alkylation of cyclic amines with alcohols catalyzed by Ru(II) complexes bearing N-Heterocyclic carbenes(Pergamon-Elsevier Science Ltd, 2018) Ulu, Oznur Dogan; Gurbuz, Nevin; Ozdemir, IsmailThis paper includes the synthesis of 2-(1,3-dioxane-2-yl)ethyl substituted benzimidazole substituted N-heterocyclic carbenes precursors and their ruthenium complexes. Synthesized compounds were characterized by elemental analysis and NMR spectroscopy. All complexes have been tested in the alkylation of pyrrolidine and morpholine with alcohols, showing an excellent activity in this reaction. (C) 2017 Published by Elsevier Ltd.Öğe Alkylation of morpholine and prolidine by phthalimide substituted Ru(II)- NHC catalysts(Pergamon-Elsevier Science Ltd, 2024) Akkoc, Mitat; Gurbuz, Nevin; Ozdemir, IsmailIn this study, a series of benzimidazolium salts and silver-benimidazol-2-ylidene complexes were synthesized. The obtained silver complexes were converted into Ru(II)- benimidazol-2-ylidene complex using the transmetallation method. After elucidating the structures of these Ru(II)-NHC compounds, the synthesized ruthenium complexes were used in the alkylation reaction of cyclic amines to synthesize valuable derivatives such as pyrrolidine and morpholine. Pyrrolidine derivatives are extensively studied for their antimicrobial, antiviral, antifungal, anticancer, anti-inflammatory, anticonvulsant, cholinesterase inhibition, and carbonic anhydrase inhibition properties. Morpholine derivatives are particularly studied in the context of central nervous system (CNS) diseases. The yield of the catalytic products obtained was determined by GC. High selectivity and yield were achieved in the alkylation reactions of heterocyclic structures.Öğe Amine-functionalized benzimidazolium salts: Synthesis, structural characterization, hirshfeld surface analysis and theoretical studies(Elsevier, 2021) Celepci, Duygu Barut; Yigit, Beyhan; Yigit, Murat; Ozdemir, Ismail; Aygun, MuhittinThe benzimidazolium salts were prepared by quaternazition of 1-(2-diisopropylaminoethyl)benzimidazoles in N,N-dimethylformamide with alkyl halides. The salts were characterized spectroscopically and their crystal structures were determined by the single-crystal X-ray diffraction method. The H-1 NMR and C-13 NMR and FT-IR features were also characterized by using Density Functional Theory at B3LYP level with 6-31G* basis set and were compared to the experimental ones. Detailed vibrational assignments of the wavenumbers were performed based on the potential energy distribution (PED) analysis. Quantum chemistry calculations of geometries, electronic properties (FMOs) and reactivity features of the compounds were investigated using the same level of the DFT theory. Natural bond orbital (NBO) analysis was used to analyze the stability of the molecules arising from hyperconjugative interactions and charge delocalization. Global reactivity descriptors were calculated to understand the biological activity behaviors. Additionally, the 3D Hirshfeld surfaces and the associated 2D fingerprint plots were carried out to obtain an insight into the behavior of the interactions in the compounds. A predictive study for the biological activities of the compounds was done using PASS online software and compared to the DFT results. (C) 2021 Elsevier B.V. All rights reserved.Öğe Anticancer activities of manganese-based photoactivatable CO-releasing complexes (PhotoCORMs) with benzimidazole derivative ligands(Springer, 2017) Ustun, Elvan; Ozgur, Aykut; Coskun, Kubra A.; Dusunceli, Serpil Demir; Ozdemir, Ismail; Tutar, YusufCarbon monoxide is an important signaling molecule which is produced by heme oxygenase-1. CO shows antiproliferative activity against cancer cells; hence, activation of HO-1 is a significant inhibition strategy against tumor formation and survival of cancer cells. In this work, manganese-based CO-releasing molecules (CORMs) were designed and synthesized to inhibit breast cancer cell proliferation. Human invasive ductal breast cancer cells (MCF-7) were treated with the synthesized CORMs to investigate the effect of the complexes on breast cancer survival under UV light. In vitro experiments indicated that the complexes inhibited breast cancer cell proliferation, and further, the antiproliferative effects were increased under UV light. Thus, these novel CORMs may provide a drug template for the treatment of invasive ductal breast cancer.Öğe Anticancer, antimicrobial and antiparasitical activities of copper(I) complexes based on N-heterocyclic carbene (NHC) ligands bearing aryl substituents(Taylor & Francis Ltd, 2020) Touj, Nedra; Al Nasr, Ibrahim S.; Koko, Waleed S.; Khan, Tariq A.; Ozdemir, Ismail; Yasar, Sedat; Mansour, LamjedNew benzimidazolium salts were synthesized as N-heterocyclic carbene precursors. These NHC precursors were metallated with Cu2O and CuI in acetone and water under reflux to give novel copper(I) complexes. The structures of these benzimidazolium salts and copper(I) complexes were characterized on the basis of elemental analysis, H-1 NMR, C-13 NMR, IR and LC-MS spectroscopic techniques. The (NHC)Cu(I) complexes 3-4 were tested against MCF7 and MDA-MB-231 cancer cells, Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA) and Candida albicans microorganisms, Leishmania major promastigotes and amastigotes, Toxoplasma gondii parasites and against Vero cell line in vitro. The synthesized copper NHC carbene complex 4b (1,3-bis(2,3,4,5,6-pentamdthylbenzyl)-2,3-dihydro-1H-benzo[d]imidazol-2-yl)copper(I) chloride) was the most active against MCF7 cancer cells (half growth Inhibition Concentrations (IC50) = 0.3 mu g mL(-1)), as well as the most potent antimicrobial against E. coli (inhibition zone (IZ) = 23.3 mm), MRSA (IZ = 25.5 mm) and C. albicans (IZ = 28.5 mm) besides its antileishmanial activities against L. major promastigotes and amastigotes (IC50 < 0.04 mu g mL(-1)). Compound 4c (1,3-bis(4-(tert-butyl)benzyl)-2,3-dihydro-1H-benzo[d]imida-zol-2-yl)copper(II) bromide) is the most potent anticancer against MDA-MB-231 cancer cells IC50 = 0.4 mu g mL(-1)). Compound 4e (5,6-dimethyl-1,3-bis(2,4,6-trimethylbenzyl)-2,3-dihydro-1H-benzo[d]imidazol-2-yl)copper(I) chloride) is the best suitable antitoxoplasmal drug candidate due to its SI of 16.5. These candidates need further study to identify mode of action and drug standardization.Öğe Antimicrobial activity, inhibition of biofilm formation, and molecular docking study of novel Ag-NHC complexes(Elsevier Science Sa, 2021) Sahin, Neslihan; Ustun, Elvan; Tutar, Ugur; Celik, Cem; Gurbuz, Nevin; Ozdemir, IsmailIn this study, we reported the synthesis of a new series of Silver(I)-N-heterocyclic carbene complexes which were obtained from the corresponding new N-heterocyclic carbene (NHC) precursors. All new compounds were characterized by elemental analysis, FT-IR, LC-MS, H-1 NMR, and C-13{H-1} NMR spectroscopy. These new N-heterocyclic carbene precursors and Ag(I)-NHC complexes were evaluated for their antibacterial, antifungal, and antibiofilm activities. The biological activities of synthesized products were compared with standard drugs. All compounds have moderate antibacterial and antibiofilm activities. In particular, while compound 2a was found to be the best inhibitor of E. coli biofilms, while compound 2d inhibited C. albicans biofilm at the highest rate. All the compounds were also analyzed by molecular docking methods with the certain target molecules. (C) 2021 Elsevier B.V. All rights reserved.Öğe Applications of quinoxaline-bridged bis(benzimidazolium) salts as ligand sources for the palladium-catalyzed Suzuki and Heck cross-coupling reactions in an aqueous medium(Wiley-V C H Verlag Gmbh, 2022) Dusunceli, Serpil Demir; Sahan, Mehmet Hanifi; Kaloglu, Murat; Ustun, Elvan; Ozdemir, IsmailIn the present work, quinoxaline-bridged bis(benzimidazolium) salts were prepared by the reaction of 2,3-bis(bromomethyl) quinoxaline and 1-substituted benzimidazole. The structures of the bis(benzimidazolium) salts were characterized by NMR, FT-IR, and elemental analysis techniques. Also, the photophysical properties of salts were investigated by UV-Vis absorption and fluorescence emission spectroscopy. Next, these quinoxaline bridged bis(benzimidazolium) salts were used as bidentate benzimidazol-2-ylidene ligand precursors in the palladium-catalyzed Suzuki-Miyaura and Mizoroki-Heck cross-couplings. These salts exhibited moderate-to-high activity in the palladium-catalyzed cross-coupling reactions.Öğe ARYLATION OF ANILINE AND AMINES BY Pd-(N-HETEROCYCLIC CARBENE) COMPLEXES(Pergamon-Elsevier Science Ltd, 2017) Sahin, Neslihan; Dusunceli, Serpil Demir; Ozdemir, IsmailAminoarenes constitute valuable building blocks in organic synthesis and an essential skeleton ubiquitously found in ligands, agrochemicals, and pharmaceuticals. This synopsis presents recent amination methods using nitrogen-heteroatom bonds as a powerful and versatile platform to rapidly synthesize diverse aminoarenes, with transition-metal catalyzed arene C-H amination. The Buchwald-Hartwig amination has been investigated theoretically and experimentally to examine the scope of possible bases under different reaction conditions. We report examples of the palladium NHC (N-heterocyclic carbene) catalyzed amination of aryl halides with anilines and amines in the presence of dimethoxyethane solvent and potassium tertiary-butoxide as a base.Öğe Arylation of heterocyclic compounds by benzimidazole-based N-heterocyclic carbene-palladium(II) complexes(Elsevier Science Sa, 2020) Sahin, Neslihan; Gurbuz, Nevin; Karabiyik, Hande; Karabiyik, Hasan; Ozdemir, IsmailSpecific C-H bond can be activated for arylation using aryl halide without the aid of directing the group in the case of electron-rich heteroarenes. The ability to readily generate halo substituted arylated heteroarenes is important in organic chemistry since these species are important building blocks for biochemists. In this manuscript, we report the synthesis of PEPPSI type-novel benzimidazole-based N-heterocyclic carbene-palladium(II) complexes (2a-e). All of the new compounds were fully characterized by H-1, C-13{H-1} NMR and FT-IR spectra. The structures of 2c, 2d, and 2e were determined by X-ray crystallography and the prepared complexes (2a-e) were investigated as catalysts for the direct arylation of 2-n-propylthiazole, 4,5-dimethylthiazole and 2-acetylthiophene with various aryl bromides. High catalytic activity for arylation was seen reaction using only 0.5 mol% catalyst for 1 h. (C) 2019 Elsevier B.V. All rights reserved.