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Öğe 1,3-Bis(3-phenylpropyl)-1H-1,3-benzimidazole-2(3H)-selone(Wiley-Blackwell, 2011) Akkurt, Mehmet; Yilmaz, Ulku; Kucukbay, Hasan; Buyukgungor, OrhanThe title molecule, C25H26N2Se, has mirror symmetry, with the mirror plane passing through the atoms of the C=Se bond and the mid-points of the two C-C bonds of the benzene ring of the benzimidazole group. The dihedral angle between the benzimidazole ring system and the phenyl ring is 71.62 (14)degrees.Öğe 1,3-Bis(3-phenylpropyl)-1H-benzimidazol-3-ium-2-carbodithioate(Wiley-Blackwell Publishing, Inc, 2009) Akkurt, Mehmet; Yilmaz, Ulku; Kucukbay, Hasan; Gencaslan, Mustafa; Buyukgungor, OrhanThe title compound, C(26)H(26)N(2)S(2), was synthesized from bis[1,3-bis(3-phenylpropyl)benzimidazolidine-2-ylidene] and CS(2) in toluene. The molecular structure is composed of a benzimidazole ring system with two phenylpropyl substituents and a dithiocarboxylate group in the 2-position. The benzimidazole unit is essentially planar, with a maximum atomic deviation of 0.008 (2) angstrom, and makes dihedral angles of 72.72 (10) and 27.62 (12)degrees, with the two phenyl rings. The dihedral angle between the two phenyl rings is 55.98 (15)degrees. The molecular packing is stabilized by a C-H center dot center dot center dot S intermolecular hydrogen-bonding interaction and a C-H center dot center dot center dot pi interaction between a benzene H atom and the phenyl ring of a neighbouring molecule.Öğe 1,3-bis(3-phenylpropyl)benzimidazolium bromide monohydrate(Int Union Crystallography, 2008) Akkurt, Mehmet; Karaca, Selvi; Yilmaz, Ulku; Kucukbay, Hasan; Buyukgungor, OrhanIn the title compound, C25H27N2+center dot Br-center dot H2O, the benzimidazole unit is essentially planar, with a maximum deviation of 0.020 (6) angstrom. The benzimidazole unit makes dihedral angles of 83.6 (3) and 81.0 (3)degrees with the two terminal phenyl rings. The dihedral angle between the phenyl rings is 58.5 (4)degrees. In the crystal structure, there are C-H center dot center dot center dot O hydrogen bonds, a C H center dot center dot center dot pi interaction between a phenyl H atom and the phenyl ring of a neighbouring molecule, and pi-pi interaction [3.512 (3) angstrom] between the centroids of the five-membered ring and the benzene ring of the benzimidazole unit of an adjacent molecule.Öğe A novel UA-CPME-FAAS method for simultaneous determination of Pb(II), Cd(II), and Cu(II) in grape and pomegranate samples using a bis (phthalimidoethyloxy)anthraquinone ligand(Academic Press Inc Elsevier Science, 2025) Mumcu, Taskin; Mumcu, Akin; Yilmaz, UlkuIn this study, a novel ultrasound-assisted cloud point microextraction (UA-CPME) method coupled with flame atomic absorption spectrometry (FAAS) was developed for the simultaneous determination of Pb(II), Cd(II), and Cu(II) ions in fruit samples. The extraction strategy employed synthesized 1,8-bis(phthalimidoethyloxy)anthraquinone ligand, used for the first time in a CPME system. Under optimized conditions, the metal-ligand complexes were efficiently extracted into the surfactant rich phase using the nonionic surfactant Triton X-100 at mild temperature and pH. The analytical performance of the method was remarkable, with low detection limits (0.6 mu g L-1 for Pb, 0.5 mu g L-1 for Cd, and 0.4 mu g L-1 for Cu), wide linear ranges (Pb: 0.7-350, Cd: 0.7-400, Cu: 0.5-400 mu g L-1), and excellent recoveries ranging from 95.6 % to 99.4 % with relative standard deviations below 2 %. The method was successfully applied to real grape and pomegranate juice samples, high recoveries and demonstrating minimal matrix effects. Matrix-matched calibration was not required, confirming the method's robustness and selectivity across different sample types. Furthermore, the use of a non toxic surfactant and elimination of organic solvents highlight the green and eco friendly nature of the method. Overall, the proposed UA-CPME-FAAS approach offers a simple, sensitive, cost effective, and environmentally sustainable solution for trace level multimetal analysis in complex food matrices such as fruit based samples.Öğe Anticancer and Antimicrobial Activities of New Cobalt and Zinc Complex-Derived Benzimidazole Containing Nitro or Methyl Groups(Amer Chemical Soc, 2026) Yilmaz, Ozgur; Apohan, Elif; Yesilada, Ozfer; Yilmaz, Ulku; Kucukbay, HasanThe cytotoxic effects of six newly synthesized 5(6)-methyl or 5(6)-nitrobenzimidazole-derived compounds that contain cobalt and zinc on nonsmall cell lung carcinoma (A549) and healthy lung epithelial (BEAS-2B) cell lines were evaluated by MTT, caspase-3, and Western Blotting methods. Cisplatin was also used as a reference compound. Compound 4 and compound 5 exhibited high cytotoxic activity against A549. While the IC50 value of cisplatin was 14.31 mu M, IC50 values of compound 4 and compound 5 were 10.30 and 7.01 mu M on A549 cells at 72 h, respectively. On the other hand, for BEAS-2B cells, the IC50 values of cisplatin, compound 4, and compound 5 were 5.91, 90.13, and 51,68 mu M, respectively. The results showed that although compounds 4 and 5 have high cytotoxicity on A549 cells, similar to cisplatin, they are less cytotoxic to BEAS-2B cells than cisplatin. The antibacterial and antifungal properties of the synthesized compounds were also investigated using minimum inhibitory concentration method. Their antimicrobial activities were tested against the Gram-negative bacteria Escherichia coli ATCC 25922 and Pseudomonas aeruginosa ATCC 27853, Gram-positive Staphylococcus aureus ATCC 29213, and yeast species Candida albicans ATCC 90028 and Candida tropicalis. The compounds showed notable antimicrobial activity against these pathogenic bacteria and yeasts.Öğe Application of endobronchial ultrasound-guided transbronchial needle aspiration for re-biopsy in lung cancer(2021) Akin Kabalak, Pinar; Kizilgoz, Derya; Yilmaz, Ulku; Demirag, FundaAim: The initial mutation status of non-small cell lung cancer (NSCLC) is important for guiding treatment. However, re-biopsy is needed to determine the new mutation status in patients receiving targeted therapy or who develop resistance during first-line therapy. Endobronchial ultrasound (EBUS) is an important tool to obtain adequate tissue for molecular analyses. Materials and Methods: We used a clinical database of 349 patients who were previously included in a multi-center study. Adequacy of tissue collected, new molecular profile, and treatment regimens were evaluated. Results: A total of 50 patients (median age of 60 ± 9 years) received biopsy by EBUS. The success rate was 36% (n = 18), and repeat re-biopsy was performed for patients with anthracosis (n = 32). In 18 patients, only one lymph node station was sampled. Initial histopathology was adenocarcinoma in 28 patients, squamous cell carcinoma (SCC) in 18 patients, and not otherwise specified (NOS) in four patients. No correlation was found between initial treatment type and success rate of the procedure (p = 0.101). After re-biopsy in six patients (five of whom had newly detected mutations), targetable mutations were detected for T790M (n = 2), EGFR-exon 19 (n = 1), c-Met (n = 1), and EGFR-21 (n = 2). Conclusion: In cases of resistance to treatment, re-biopsy should be performed to detect different gene amplifications. Re-biopsy with EBUS is an effective method for an appropriate progressive lesion.Öğe Bisbenzimidazole salts and their in silico-in vitro inhibitory abilities on hCA I, hCA II, and AChE enzymes(Springer Wien, 2024) Yilmaz, Ulku; Demir, Yeliz; Tok, Tugba Taskin; Gok, Yetkin; Aktas, Aydin; Gulcin, IlhamiEight new bisbenzimidazolium halides were prepared from alkyl halides and 4,4 '-bis[(benzimidazol-1-yl)methyl]-1,1 '-biphenyl.The structures of the benzimidazole salts were characterized using elemental analysis techniques as well as 1H, 13C NMR, and FT-IR spectroscopic methods. The inhibitory effects of the benzimidazole derivatives were measured against human carbonic anhydrase I (hCA I), human carbonic anhydrase II (hCA II), and acetylcholinesterase (AChE) enzymes. All benzimidazolium halides exhibited significant enzyme inhibitory properties. They showed highly potent inhibitory effect on AChE and hCAs (Ki values are in the range of 15.7 +/- 0.8 to 49.7 +/- 10.1 nM, 14.6 +/- 1.5 to 70.7 +/- 2.7 nM, and 17.4 +/- 2.8 to 38 +/- 10 nM for AChE, hCA I, and hCA II, respectively). The binding orientation of the synthesized bisbenzimidazolium halides was evaluated by molecular docking studies, reflecting the importance of the p-methylbenzyl, m-methylbenzyl, p-nitrophenethyl, and 3-(1,3-dioxoisoindolin-2-yl)methyl) groups in protein-ligand interaction. The docking results support the Ki values of the respective compounds in this study. The structure-activity relationships against the various targets are clearly shown in three dimensions at the atomic level by their interactions with the mentioned enzymes.Öğe Effects of new NHC derivatives as ligands in the Suzuki-Miyaura reaction(Taylor & Francis Inc, 2021) Yilmaz, Ulku; Kucukbay, HasanA series of NHC-derivative ligands was synthesized from bisbenzimidazole salts as the precursor of N-heterocyclic carbene with chalcogens, carbon disulfide, and phenyl isothiocyanate reagents. These new ligands were used in the Suzuki-Miyaura cross-coupling reaction in the presence of palladium(II) acetate. Particularly, it was observed a remarkable ligand activity with tellurourea (5).Öğe Emission based sensing of N-acetyl cysteine via silver equipped anthraquinone derivatives(Pergamon-Elsevier Science Ltd, 2026) Mumcu, Taskin; Oncuoglu, Serkan; Mumcu, Akin; Yilmaz, Ulku; Ertekin, KadriyeIn this work we investigated emission-based response of silver complexes of two newly synthesized anthraquinone derivatives for N-acetylcysteine (NAC) and thioglycolic acid. The interaction of the probes, DHAdibenzonitrile and DHA-dibutanenitrile with silver nanoparticles resulted in metal chelation and following quenching of the fluorescence. To determine whether the emission intensity of the complexes was re-stored again, thiol compounds; NAC and thioglycolic acid were used. The released dyes re-emitted light, allowing the system to exhibit an intensity-based turn-on type sensor behavior for the NAC and thioglycolic acid, respectively. The re-stored fluorescence was monitored as a strong emission based analytical signal at 560 nm. The complex stoichiometries were investigated using several approaches, including Job's plot, density functional theory (DFT) and FT-IR measurements. The findings relying on HOMO-LUMO and energy gap calculations highlight that Ag coordination and following acetylcysteine adduction significantly re-shape both local nucleophilic and electrophilic regions, modulating the global electronic structure and reactivity of anthraquinone derivatives. N-acetylcysteine exhibited an exceptional spectral response at pH 9.0 in a buffered solution exhibiting 13.6 and 14.4-fold enhancement in the emission intensity, respectively. The reported linear responses for a concentration range of; 1.0 x 10-5 M-1.0 x 10-2 M, can easily be adopted to determination of the NAC levels in drugs, in vitro studies or in serum samples. Limit of detection (LOD) and limit of quantification (LOQ) values of the DHA-dibutanenitrile derivative for the NAC molecule were found to be 1.28 x 10-6 and 1.21 x 10-5 mol x L-1, respectively. Similarly, the DHA-dibenzonitrile exhibited 1.11 x 10-6 and 1.28 x 10-5 mol x L-1 of LOD and LOQ values, respectively.Öğe Evaluation, synthesis and structural properties of stable bisbenzimidazolium tetrafluoroborates derived from unstable benzotetraazafulvalenes(Arkat Usa Inc, 2022) Yilmaz, Ulku; Kucukbay, HasanThe stable dicationic tetrafluoroborate salts of tetraazafulvalenes were synthesized with unstable N -heterocyclic carbenes or enetetramines derived from benzimidazolium and bridged-bisbenzimidazolium halides. The structural characterizations of all the compounds were determined via spectroscopic methods 1H-NMR, 13C-NMR, IR, and MS and by elemental analysis respectively. Also, the effect of compound 1 as a ligand on the catalytic system was evaluated in the Suzuki-Miyaura reaction.Öğe Microwave Assisted Catalytic Activity of Some bis-5(6)-Nitrobenzimidazole Salts for Heck and Suzuki Cross-Coupling Reactions(Asian Journal Of Chemistry, 2010) Sireci, Nihat; Yilmaz, Ulku; Kucukbay, HasanA mixture of bis-5(6)-nitrobenzimidazole salts (2a-h), Pd(OAc)(2) and K2CO3 in DMF-H2O catalyzes, in good yield the Suzuki and Heck cross-coupling reactions for synthesis of biaryl and stilbene derivatives assisted by microwave irradiation in the short time.Öğe Microwave Assisted Suzuki-Miyaura and Ullmann Type Homocoupling Reactions of 2-and 3-Halopyridines Using a Pd(OAc)2/Benzimidazolium Salt and Base Catalyst System(Mdpi, 2013) Yilmaz, Ulku; Deniz, Selma; Kucukbay, Hasan; Sireci, NihatA number of novel benzimidazole derivatives 1-4 were synthesized and the catalytic activity of these compounds in a catalytic system consisting of a benzimidazolium salt/Pd(OAc)(2)/K2CO3 were investigated in the Suzuki-Miyaura and Ullmann type homocoupling reactions under microwave irradiation. We obtained both cross coupling and homocoupling products of pyridine and some side products such as dimethylaminopyridine and unsubstituted pyridine.Öğe A study about excellent xanthine oxidase inhibitory effects of new pyridine salts(Springer Wien, 2021) Yilmaz, Ulku; Noma, Samir Abbas Ali; Tok, Tugba Taskin; Sen, Betul; Gok, Yetkin; Aktas, Aydin; Ates, BurhanA series of pyridine salts were synthesized containing vitamin B3 (niacin), isonicotinonitrile, and non-substituted pyridine fragment from reactions of 1,3-dibromopropane, 1,4-dibromobutane, and 4,4 '-bis(chloromethyl)-1,1 '-biphenyl reactants with pyridines. The builds of pyridine salts were identified by dint of IR, H-1, and C-13 NMR spectroscopic techniques, and CHN analyses. Therewithal, the build of a compound was assigned via the X-ray single-crystal diffraction method. 1,3-Bis(3-cyanopyridine-1-ium-1-yl)propane dibromide crystallizes in the orthorhombic space group Ccce, with half of the cation molecule and one bromide anion in the asymmetric unit. Enzyme inhibitory properties of pyridine compounds were tested on the activities of xanthine oxidase (XO) and determined in the range from 0.394 to 0.623 mu M. All of the compounds inhibited enzyme more effectively than allopurinol that which is a standard drug. In addition, docking calculations were applied to investigate the binding properties and interactions of pyridine salts towards XO. Graphic abstractÖğe Synthesis a group of 5(6)-substituted benzimidazole Zn(II) and Co(II) complexes and investigation their cytotoxic and antimicrobial activities(Wiley, 2022) Yilmaz, Ulku; Apohan, Elif; Kucukbay, Hasan; Yilmaz, Ozgur; Tatlici, Eray; Yesilada, OzferA series of 5(6)-substituted benzimidazole ligand-zinc(II) and cobalt(II) complexes were synthesized and characterized by H-1, C-13 NMR, IR, CHN analysis techniques. In vitro, anticancer and antimicrobial activities of ligand and complexes were evaluated. The cytotoxic activities of compounds were investigated against the human lung adenocarcinoma (A549) cell lines and healthy human lung bronchial epithelium (BEAS2B) cells. Compounds 1, 6, and 8 were observed to exhibit higher cytotoxic activity than the others at the 72nd hour. Also, the compounds showed varying degrees of antimicrobial activity against the microorganisms used. Compounds 1, 5, and 8 were most effective against standard strains Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 29213. As for the antifungal activity, compounds 1, 5, 6, and 8 showed high antifungal activity against the yeast type fungi Candida albicans ATCC 90028 and Candida tropicalis.Öğe Synthesis and characterization of novel phosphoramidates containing benzimidazole moiety(Taylor & Francis Ltd, 2016) Yilmaz, Ulku; Kucukbay, HasanNovel heterocyclic phosphoramidates were synthesized by a nucleophilic substitution reaction of 2-substitutedbenzimidazoles and diphenyl chlorophosphate (ClPO3Ph2) in the presence of potassium hydroxide (KOH) under an argon atmosphere. The structures of the phosphoramidates were characterized by NMR, IR, melting point, and elemental analysis. [GRAPHICS] .Öğe Synthesis and characterization of substituted benzimidazole Co(II), Fe(II), and Zn(II) complexes and structural characterization of dichlorobis{1-[2-(1-piperidinyl)ethyl]-1H-benzimidazole-K N3} zinc(II)(Tubitak Scientific & Technological Research Council Turkey, 2015) Kucukbay, Hasan; Yilmaz, Ulku; Akkurt, Mehmet; Buyukgungor, OrhanThe Co(II), Fe(II), and Zn(II) complexes of 1-(3-phenyl)propylbenzimidazole (PPBI), 5-nitro-1-(3-phenyl) propylbenzimidazole (PPNBI), 1-[2-(4-morpholinyl)ethyl]benzimidazole (MEBI), 1-[2-(1-piperidinyl)ethyl]benzimidazole (PEBI), and 5-nitro-1-[2-(1-piperidinyl)ethyl]benzimidazole (PENBI) were synthesized and characterized by H-1 NMR, C-13 NMR, and elemental analyses. The magnitudes of the magnetic moments for paramagnetic complexes were between 4.07 and 5.11 B.M. Moreover, the crystal structure of dichlorobis{1-[2-(1-piperidinyl)ethyl]-1 H-benzimidazole-(K) N-3} zinc(II) was determined by single crystal X-ray diffraction.Öğe Synthesis and evaluation of anticancer properties of novel benzimidazole ligand and their cobalt(II) and zinc(II) complexes against cancer cell lines A-2780 and DU-145(Elsevier Science Sa, 2019) Yilmaz, Ulku; Tekin, Suat; Bugday, Nesrin; Yavuz, Kemal; Kucukbay, Hasan; Sandal, SuleymanEighteen new cobalt(II) or zinc(II) complexes of benzimidazole bearing 1-benzyl and 2-phenyl moieties were synthesized from the reaction of appropriate benzimidazole ligands and CoCl2 or ZnCl2. Their structural characterizations were done by IR, NMR (H-1, C-13) and UV-VIS spectrometers. Cytotoxic activities of eighteen new complexes and three benzimidazole ligands were determined using A-2780 (human ovarian) and DU-145 (human prostate) cell lines. Antitumor properties of all compounds were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell viability assay for the tested benzimidazole derivatives was performed and the LogIC(50) values of the compounds were calculated after a 24-hour treatment. All tested benzimidazole derivatives showed higher or comparable antitumor activity against A-2780 cell lines compared to the standard drug docetaxel with a LogIC(50) value of -0.81 mu M (p < 0.05). Eight of the examined compounds (1, 3, 5, 6, 7, 9, 10 and 13) showed high cytotoxic activity against A-2780 compared to the standard drug docetaxel. While the LogIC(50) of the docetaxel was -0.81 mu M for A-2780 cells at 24 h, the IC50 values of compounds 1, 3, 5, 6, 7, 9, 10 and 13 were - 0.97, -1.30, - 0.22, 0.13, - 0.16, - 0.73 and - 0.53 mu M, respectively. Three of the compounds 1, 18 and V showed high cytotoxic activity against DU-145 compared to docetaxel (p < 0.05). While the LogIC(50) of the docetaxel was -1.13 mu M for DU-145 cells at 24 h, the LogIC(50) values of compounds 1, 18 and V were 0.84, -0.38 and -0.66 mu M, respectively.Öğe Synthesis and Properties of New Endotricyclic Electron-Rich Olefins and Their Some Derivatives(Asian Journal Of Chemistry, 2009) Yilmaz, Ulku; Kucukbay, HasanNew endotricyclic electron rich olefins (1 and 10) were synthesized and their new bisbenzimidazole derivatives were obtained from reaction of group 16 elements, PhNCS, CS(2) and CH(3)CN. Structure of all new compounds were identified by (1)H NMR, (13)C NMR, FT-IR spectroscopic techniques and elemental analysis. The catalytic activity of the electron-rich olefin, 1 on the benzoin condensation reaction were also investigated.Öğe Synthesis and spectral characterization of new benzimidazolium compounds containing sulfur(Taylor & Francis Ltd, 2020) Yilmaz, Ulku; Kucukbay, HasanN-heterocyclic carbene (compound b) was synthesized from reaction of 1-(3-phenylpropyl)-3-methylbenzimidazolium iodide (a) and a strong base in an argon atmosphere. Then, 1-(3-phenylpropyl)-3-methylbenzimidazolium-2-carbodithioate (c) was prepared with carbene and CS2. Finally, a group of alkyl 1-(3-phenylpropyl)-3-methylbenzimidazolium-2-carbodithioate halides was synthesized with alkyl halides and compound c, occurring products 1-6. Structural characterization of compounds was performed H-1, and C-13 NMR, IR, and MS spectroscopy and elemental analysis.Öğe Synthesis of 1-substituted benzimidazole metal complexes and structural characterization of dichlorobis(1-phenyl-1H-benzimidazole-?N3)cobalt(II) and dichlorobis (1-phenyl-1H-benzimidazole-?N3)zinc(II)(Taylor & Francis Ltd, 2011) Sireci, Nihat; Yilmaz, Ulku; Kucukbay, Hasan; Akkurt, Mehmet; Baktir, Zeliha; Turktekin, Sevim; Buyukgungor, OrhanThe Co(II), Zn(II), Ni(II), Cu(II), and Fe(II) complexes of 1-phenylbenzimidazole were synthesized and characterized by NMR and elemental analyses. The crystal structures of dichlorobis(1-phenyl-1H-benzimidazole-kappa N-3) cobalt(II) and dichlorobis(1-phenyl-1H-benzimidazole-kappa N-3)zinc(II) have been determined by single-crystal X-ray diffraction.
