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Öğe Benzimidazole based a new therapeutic agent effective on ovarian cancer cells(Wiley-Blackwell, 2015) Tekin, Suat; Mumcu, Akin; Kucukbay, Hasan; Sandal, Suleyman[Abstract Not Available]Öğe Concentration effects of some new benzimidazole derivatives on Human Breast Cancer Cell Viability(Wiley-Blackwell, 2015) Tekin, Suat; Mumcu, Akin; Kucukbay, Hasan; Sandal, Suleyman[Abstract Not Available]Öğe Determination of pKa values of some novel benzimidazole salts by using a new approach with 1H NMR spectroscopy(Wiley-Blackwell, 2015) Mumcu, Akin; Kucukbay, HasanBenzimidazoles and their derivatives including imidazole are studied widely because they exist in the structure of natural products and different drugs. pK(a) values are extremely important for drug discovery and improvement in order to determine pharmacokinetic and pharmacodynamic features such as permeation through biological barriers, interactions with the target area or side effects. Acid-base features (pK(a)) have great importance not only for physiological characteristics but also for being used as a ligand or changing physico-chemical features by turning benzimidazoles into salts. Within the scope of this study, a variety of new benzimidazole salts were synthesized, and their characterizations were made by NMR spectroscopy, FTIR spectroscopy and element analysis techniques. The pK(a) values of synthesized benzimidazole saltswere determined by inflection point approach using integration values obtained with H-1 NMR spectroscopy and Henderson-Hasselbalch analysis. pK(a) values of some benzimidazole salts were also determined by potentiometric methods in order to compare those of NMR spectroscopy results. Copyright (C) (C) 2015 John Wiley & Sons, Ltd.Öğe A different approach to the quantification of human seminal plasma metabolites using high-resolution NMR spectroscopy(Elsevier, 2023) Mumcu, AkinIn this study, a reliable method was established for the absolute quantification of metabolite concentrations in human seminal plasma using ERETIC2, a quantification tool developed by Bruker based on the PULCON principle. The performance of the ERETIC2 was examined using an AVANCE III HD NMR spectrometer (600 MHz) equipped with a triple inverse 1.7 mm TXI probe in terms of some experimental parameters that may affect the accuracy and precision of the quantitative results. Then, the accuracy, precision, and repeatibility of ERETIC2 were determined using L-asparagine solutions at different concentrations. And it was evaluated by comparing it with the classical internal standard (IS) quantification method. The relative standard deviation (RSD) values for ERETIC2 were calculated in the range of 0.55-1.90% and the minimum recovery value was 99.9%, while the RSD values for the IS method were calculated in the range of 0.88-5.83% and recovery value was minimum 91.0%. Besides, the RSD values of the inter-day precisions for the ERETIC2 and IS methods were obtained to be in the range of 1.25 - 3.03% and 0.97 - 3.46%, respectively. Finally, the concentration values of seminal plasma metabolites were determined using different pulse programs with both methods for samples obtained from normozoospermic control and azoospermic patient groups. The results proved that this quantification method developed using NMR spectroscopy is easy to use in complex sample systems such as biological fluids and is a good alternative to the classical internal standard method in terms of accuracy and sensitivity. In addition, the improvement of the spectral resolution and sensitivity with the microcoil probe technology and the possibility of analyzing with minimum sample quantities has contributed positively to the results of this method.Öğe Metabolomic analysis of endometrial cancer by high-resolution magic angle spinning NMR spectroscopy(Springer Heidelberg, 2022) Duz, Senem Arda; Mumcu, Akin; Dogan, Berat; Yilmaz, Ercan; Coskun, Ebru Inci; Saridogan, Erdinc; Tuncay, GorkemPurpose To analyze endometrial metabolite profiles between patients with endometrial cancer and controls. Methods Seventeen (17) women with endometrium cancer and 18 controls were enrolled in this study. H-1 HR-MAS (High Resolution-Magic Angle Spinning) NMR (Nuclear Magnetic Resonance) spectroscopy data obtained from endometrial tissue samples of patients with endometrial cancer and control group were analyzed with bioinformatics methods. Results Principal component analysis (PCA) and the partial least squares discriminant analysis (PLS-DA) score plots obtained with the multivariate statistical analysis of pre-processed spectral data shows a separation between the samples from patients with endometrial cancer and controls. Analysis results suggest that the levels of lactate, glucose, o-phosphoethanolamine, choline, glycerophosphocholine, phosphocholine, leucine, isoleucine, valine, glutamate, glutamine, n-acetyltyrosine, methionine, taurine, alanine, aspartate and phenylalanine are increased in patients with endometrial cancer compared to the controls. Conclusion The metabolomics signature of patients with endometrial cancer is different from that of benign endometrial tissue.Öğe Metabolomics analysis of follicular fluid in women with ovarian endometriosis undergoing in vitro fertilization(Taylor & Francis Inc, 2019) Karaer, Abdullah; Tuncay, Gorkem; Mumcu, Akin; Dogan, BeratThe purpose of this study was to investigate whether a change in the follicular fluid metabolomics profile due to endometrioma is identifiable. Twelve women with ovarian endometriosis (aged<40 years, with a body mass index [BMI] of <30 kg/m(2)) and 12 age- and BMI-matched controls (women with infertility purely due to a male factor) underwent ovarian stimulation for intracytoplasmic sperm injection (ICSI). Follicular fluid samples were collected from both of groups at the time of oocyte retrieval for ICSI. Next, nuclear magnetic resonance (NMR) spectroscopy was performed for the collected follicular fluids. The metabolic compositions of the follicular fluids were then compared using univariate and multivariate statistical analyses of NMR data. Univariate and multivariate statistical analyses of NMR data showed that the metabolomic profiles of the follicular fluids obtained from the women with ovarian endometriosis were distinctly different from those obtained from the control group. In comparison with the controls, the follicular fluids of the women with ovarian endometriosis had statistically significant elevated levels of lactate, beta-glucose, pyruvate, and valine. We conclude that the levels of lactate, beta-glucose, pyruvate, and valine in the follicular fluid of the women with endometrioma were higher than those of the controls.Öğe Metabolomics analysis of placental tissue obtained from patients with fetal growth restriction(Wiley, 2022) Karaer, Abdullah; Mumcu, Akin; Arda, Senem; Tuncay, Gorkem; Dogan, BeratAim The aim of this study was to determine whether there was a difference in placental metabolite profiles between patients with fetal growth restriction (FGR) and healthy controls. Methods The study included 10 patients with FGR diagnosis with 14 healthy controls with both matched maternal age and body mass index. H-1 HR-MAS NMR spectroscopy data obtained from placental tissue samples of patients with FGR and healthy control group were analyzed with bioinformatics methods. The obtained results of metabolite levels were further validated with the internal standard (IS) quantification method. Results Principal component analysis (PCA) and the partial least squares discriminant analysis (PLS-DA) score plots obtained with the multivariate statistical analysis of preprocessed spectral data shows a separation between the samples from patients with FGR and healthy controls. Bioinformatics analysis results suggest that the placental levels of lactate, glutamine, glycerophosphocholine, phosphocholine, taurine, and myoinositol are increased in patients with FGR compared to the healthy controls. Conclusions Placental metabolic dysfunctions are a common occurrence in FGR.Öğe Ruthenium, rhodium and iridium complexes of a silyl-substituted N-heterocyclic carbene ligand and their catalytic performance in hydrosilylation of terminal alkynes(Elsevier Science Sa, 2023) Mumcu, Akin; Karatas, Mert Olgun; Ozdemir, Namik; Erdogan, Ali; Kucukbay, HasanHerein, [Ru(NHC)(p-cymene)Cl-2] (3) and [MCl(NHC)(cod)] (M=Rh (4) or Ir (5)) (cod=1,5-cyclooctadiene) complexes of a silyl-substituted N-heterocyclic carbene ligand (NHC) have been prepared by the transmetalation reaction between Ag-NHC (2) and corresponding starting metal compound. The characterization of the complexes has been completed by NMR spectroscopy and elemental analyses. Solid state structures of Ag- (2) and Rh-NHC (4) have also been determined by single crystal X-ray analysis. [RhCl(NHC)(CO)(2)] type bis-carbonyl complex (6) has also been prepared and CO stretching frequencies pointed the strong s-donor ability of the silyl-substituted NHC. The catalytic activity of all complexes have been examined in hydrosilylation of terminal alkynes. Among the complexes, Ir-NHC has been found out as active catalyst with around 90% conversion and beta-(Z) selectivity at room temperature. Further studies revealed that this complex is able to maintain its stability in catalytic reaction conditions, chemoselective to alkynes in the presence of alkenes, and operable in scale-up reactions. In contrast, bis-carbonyl Rh-NHC performed 82% beta-(Z) selectivity with full conversion of alkyne in first 4 h of reaction, but when reaction time was extended to 24 h, almost all beta-(Z) vinylsilane isomerised to thermodynamically more stable beta-(E). (c) 2023 Elsevier B.V. All rights reserved.Öğe Silver and ruthenium complexes with anthracene functionalized N-heterocyclic carbene ligands: catalytic and cytotoxicity properties(Springer, 2024) Karatas, Mert Olgun; Kelestemur, Unzile; Mumcu, Akin; Ozdemir, Namik; Erdogan, Ali; Kucukbay, HasanIn this study, we have synthesized two Ag (2a and 2b) and two Ru (3a and 3b) complexes with anthracene substituted N-heterocyclic carbene (NHC) ligands. Ag-NHC complexes have been synthesized by the interaction of corresponding benzimidazolium chloride and Ag2O. Ru-NHC complexes have been synthesized by the transmetalation reaction between corresponding Ag-NHC and [RuCl2(p-cymene)]2 dimer. The synthesized complexes have been characterized by elemental analysis, NMR (1H and 13C NMR), and mass (high resolution mass spectroscopy, HRMS) spectroscopic techniques. In order to assess the catalytic potential of the Ru-NHC complexes, we have conducted experiments involving the hydrosilylation of terminal alkynes. Both complexes have exhibited a moderate level of catalytic activity, achieving conversions ranging from 70 to 90%, along with a substantial beta-(Z) selectivity within the range of 80-90%. Furthermore, we have also subjected the benzimidazolium chlorides (1a and 1b), Ag-NHCs and Ru-NHCs to cytotoxicity testing using human breast cancer cells (MCF-7) and human colorectal cancer cells (Caco-2). The results of these assays have demonstrated that all compounds strongly inhibit the proliferation of both cell lines.Öğe Synthesis and evaluation of novel N, N'-disubstituted benzimidazolium bromides salts as antitumor agents(Tubitak Scientific & Technological Research Council Turkey, 2016) Kucukbay, Hasan; Mumcu, Akin; Tekin, Suat; Sandal, SuleymanNovel benzimidazolium bromides salts having (4-methoxyphenyl)ethyl, (phthalimide-2-yl)methyl, 4-nitrobenzyl, 2-phenylethyl, penthyl, or allyl groups were synthesized and their characterizations were conducted by H-1 and C-13 NMR and IR spectroscopic methods, and microanalysis. In vitro antitumor activities of the novel benzimidazole compounds (1-7) were determined by using ovarian (A2780) and prostate (PC-3) cancer cell lines. Antitumor properties of all compounds were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MIT) assay. A time-dependent cell viability assay for the tested benzimidazole compounds was performed and the IC50 values of the compounds were calculated after treatment for 24 and 48 h. Our results indicate that the tested benzimidazole compounds show antitumor activity against A2780 and PC-3 cell lines (P < 0.05).