Yazar "Dusunceli, Serpil Demir" seçeneğine göre listele
Listeleniyor 1 - 18 / 18
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Amine-fnctionalized silver and gold N-heterocyclic carbene complexes: Synthesis, characterization and antitumor properties(Elsevier Science Sa, 2019) Kizrak, Umran; Ciftci, Osman; Ozdemir, Ilknur; Gurbuz, Nevin; Dusunceli, Serpil Demir; Kaloglu, Murat; Mansour, LamjedDiisopropilamine-tethered benzimidazolium salts have been prepared as precursors for Ag(I)-NHC and Au(I)-NHC complexes. These NHC ligands were metallated with Ag2O on moderate conditions to give novel silver-NHC complexes. Gold-NHC complexes have been obtained by transmetalation using the silver-NHC precursor. The structures of all compounds were characterized by H-1 NMR, C-13 NMR, IR and elemental analysis techniques. The cytotoxic properties of the silver(I) and gold(I) complexes have been assessed in various human cancer lines, including cisplatin-sensitive and resistant cell. IC50 values of these four complexes were determined by the MTS based assay on three human cancer cell lines (SHSY5Y, HTC116 and HEP3B) and human healthy cell line (HF). These silver and gold N-heterocyclic carbene complexes have been highlighted metal-based cancer therapeutic agent with unique structures and functions. These strategies provide exciting opportunities for discovering new type metalodrug. (C) 2019 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 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 Direct arylation of heteroarenes by PEPPSI-type palladium-NHC complexes and representative quantum chemical calculations for the compound which the structure was determined by X-ray crystallography(Taylor & Francis Ltd, 2019) Sahin, Neslihan; Serdaroglu, Goncagul; Dusunceli, Serpil Demir; Tahir, Muhammad Navaz; Arici, Cengiz; Ozdemir, IsmailIn this study, we synthesized five new PEPPSI-type Pd-NHC complexes with high yields around 78-83%. The structures of all complexes were characterized by FT-IR, H-1 NMR, and C-13{H-1} NMR spectroscopies. Further, the structure of 2c was determined by X-ray crystallography. The single-crystal structure of 2c shows that coordination geometry around Pd is distorted square planar. The Pd-NHC complexes were efficient catalysts for the direct C5-arylation of 2-n-butylthiazole, 2-n-butylfuran, and 2-n-butylthiophene with various aryl-bromides and showed high catalytic activity for arylation reaction using only 1 mol% catalyst loading at 130 degrees C for 1 h. The conversions for substrates containing electron-withdrawing groups were higher than for substituents containing electron-donating groups. In order to evaluate the catalytic activity of the complexes, representative electronic and spectroscopic simulations by DFT method have been performed for 2c. NBO analysis has revealed that the strongest interaction contributing to the lowering of the molecular stabilization energy for 2c is predicted as pi(C11-N27) -> pi*(N26-C28) with E-(2) = 73.93 kcal mol(-1). In addition, FMO analysis has implied that 2c is more chemically reactive because of its lower energy gap value. According to the other quantum chemical parameters, 2c is softer, better electrophile and has more charge-transfer capability than 1c.Öğe The first used butylene linked bis(N-heterocyclic carbene)-palladium-PEPPSI complexes in the direct arylation of furan and pyrrole(Elsevier Science Sa, 2020) Kaloglu, Murat; Dusunceli, Serpil Demir; Ozdemir, IsmailWe reported the synthesis and characterization of butylene linked bis-benzimidazole based N-heterocyclic carbene (NHC) precursors and their PEPPSI-type bimetallic Pd-complexes, and we implemented its activities in the direct C5-arylation of 2-acetylfuran and 1-methylpyrrole-2-carboxaldehyde with various aryl bromides. The catalytic activities of the synthesized palladium-complexes were found to be very high. These complexes were fully characterized by different techniques such as H-1 NMR, C-13 NMR, FT-IR spectroscopy and elemental analysis. (C) 2020 Elsevier B.V. All rights reserved.Öğe Molecular docking and electronic transition analysis of novel [Re(bbim)(bpy)(CO)3]OTf complex as a CO-releasing molecule(Scientific Publ-India, 2019) Ustun, Elvan; Celebi, Mutlu Sonmez; Sahin, Neslihan; Dusunceli, Serpil Demir; Ozdemir, IsmailSynthesis of CO-releasing molecules that safely deposit/transport CO has attracted great attention after the discovery of therapeutic properties of carbon monoxide, which is known to be a toxic gas. Metal carbonyl complexes seem to be the most important alternative as CO-releasing molecules. Recent developments in computational chemistry make it possible to gain many information about the properties of complexes before being synthesized. On the other hand, molecular docking methods can also give valuable information about the interaction of the molecules with tissue. The metal carbonyl complexes that were synthesized as a CO-releaser interact primarily with blood proteins when they enter the tissue; therefore, the theoretical analysis of the interaction of complexes with blood proteins can give useful information. In this study, [Re(bbim)(bpy)(CO)(3)]OTf (bbim: benzylbenzimidazole; bpy: 2,2'-bipyridyl, OTf: SO3CF3) complex was synthesized, characterized, analyzed by DFT/TDDFT based calculation method and docked into human serum albumin.Öğe Molybdenum Carbonyl Complexes with Benzimidazole Derivatives Against SARS-CoV-2 by Molecular Docking and DFT/TDDFT Methods(World Scientific Publ Co Pte Ltd, 2021) Ustun, Elvan; Dusunceli, Serpil Demir; Coskun, Feyzullah; Ozdemir, IsmailBenzimidazole derivative molecules attract attention of scientists due to their bioactivities. The dramatic changes in recorded activities according to the type and position of the substituents motivate synthesis and analysis of new molecules. Commercial benzimidazole-based molecules have been used in therapeutic procedures. It is known that the activities of metal complexes with benzimidazole derivative ligands have different activities when compared to the benzimidazole main structure. Nowadays, one of the most important health problems is COVID-19, which caused the pandemic that we are still experiencing. Although vaccine studies are important to overcome acute problems, regarding the possible post-vaccination adverse effects, the need for new drugs against the virus is obvious. Considering the urgency and the limited facilities during the pandemic, preliminary in silico studies of candidate molecules are essential. In this study, {[bis-(N-benzylbenzimidazole)] tetracarbonylmolybdenum}, {[bis-(N-4-chlorobenzylbenzimidazole)] tetracarbonylmolybdenum} and {[bis-(N-4-methoxybenzylbenzimidazole)] tetracarbonylmolybdenum} were synthesized and characterized. The optimization and the structural analysis of these molecules were performed by DFT/TDDFT methods. The molecules were docked into SARS coronavirus main peptidase (PDB ID: 2gtb), COVID-19 main protease in complex with Z219104216 (PDB ID: 5r82), COVID-19 main protease in complex with an inhibitor N3 (PDB ID: 6lu7) and Papain-like protease of SARS-CoV-2 (PDB ID: 6w9c) crystal structures for evaluation of their anti-viral activity. Molybdenum carbonyl complexes containing benzimidazole derivative ligands have been synthesized, characterized, and analyzed structurally by DFT/TDDFT methods. Antiviral activities of the complexes were analyzed by molecular docking methods against some important Coronavirus targets in parallel with the pandemic period we are living in. Inhibitory potency of the complexes toward COVID-19 targeted is compared to some well-known commercial antivirals.Öğe Reduction hydrogenation of imines by in situ generated rhodium NHC complexes(Elsevier, 2020) Karaca, Emine Ozge; Dusunceli, Serpil Demir; Gurbuz, Nevin; Ozdemir, IsmailIn this paper we examined the catalytic activity of in situ prepared bidentate azolium salt/[RhCl(COD)](2) catalyst system in the transfer hydrogenation of imines with i-propanol to the corresponding amine. The first in situ transfer hydrogenation of imines to amines is described using [RhCl(COD)](2) with bidentate azolium ligands. New bidentate azolium salts (1a-c, 2a-c) as NHC precursors have been synthesized and characterized. The in situ prepared three-component bidentate azolium salts (LHX)/[RhCl(COD)](2) and t-BuOK catalyzes quantitatively the transfer hydrogenation of imines under mild reaction conditions in i-propanol. The results show that bidentate benzimidazolium salts were observed to be more active in reducing imines. Moreover, the method is simple and effective against various imines. (C) 2020 Elsevier B.V. All rights reserved.Öğe Synthesis of Quinoxaline-Linked Bis(Benzimidazolium) Salts and Their Catalytic Application in Palladium-Catalyzed Direct Arylation of Heteroarenes(Springer, 2022) Kaloglu, Murat; Sahan, Mehmet Hanifi; Dusunceli, Serpil Demir; Ozdemir, IsmailIn this study, quinoxaline-linked bis(benzimidazolium) salts were synthesized as bis-N-heterocyclic carbene (NHC) precursors. These bis(NHC) precursors were used as multidentate ligands for the construction of bi(hetero)aryls by palladium-catalyzed direct C-H activation process. The in situ prepared palladium complexes by mixtures of the Pd(OAc)(2) and the bis(NHC) precursors were used as the catalyst for direct C-H activation of heteroarenes. These catalytic system exhibited a modest catalytic activity in the direct C-H activation of five-membered heteroarenes with a wide range of (hetero)aryl bromides.Öğe Synthesis of ruthenium N-heterocyclic carbene complexes and their catalytic activity for ?-alkylation of tertiary cyclic amines(Elsevier Science Sa, 2015) Ozdemir, Ismail; Dusunceli, Serpil Demir; Kaloglu, Nazan; Achard, Mathieu; Bruneau, ChristianThe novel ruthenium N-Heterocyclic carbene complexes are synthesized, and characterized by studying its H-1, C-13, elemental analysis, and X-ray. These complexes have been reported as promising catalyst for beta C-H bond functionalization of tertiary cyclic amines through hydrogen autotransfers in the presence of external acidic additive. The new catalytic products were characterized by H-1 NMR, C-13 NMR spectroscopic methods. (C) 2015 Elsevier B.V. All rights reserved.Öğe Synthesis, antimicrobial properties, and theoretical analysis of benzimidazole-2-ylidene silver(I) complexes(Taylor & Francis Ltd, 2020) Dusunceli, Serpil Demir; Ayaz, Dilek; Ustun, Elvan; Gunal, Selami; Ozdemir, Namik; Dincer, Muharrem; Ozdemir, IsmailA series of symmetrical and nonsymmetricalN,N-disubstituted benzimidazolium salts were synthesized asN-heterocyclic carbene precursors. These salts were treated with Ag2O to afford their corresponding mononuclear Ag(I)-NHC complexes. These compounds were characterized by spectroscopy techniques and analyzed by DFT/TDDFT and docking methods. Also, the structures of2aand2ewere determined by single-crystal X-ray crystallography. These new Ag-NHC complexes were screened for their antibacterial activities against Gram-positive, Gram-negative bacteria, fungi, and nosocomial agents.Öğe Synthesis, Characterization, and Effects of Calcium and Magnesium Ions on BSA-Binding Properties of Novel Quinoxaline Bridged Bis(Benzimidazolium) Salts(Wiley-V C H Verlag Gmbh, 2024) Hanifi Sahan, Mehmet; Dusunceli, Serpil Demir; Kaloglu, Murat; Ozdemir, Ismail; Ustun, ElvanMagnesium and calcium play crucial roles in many physiological processes and have been carried by serum albumin in blood plasma. This protein also helps to regulate the distribution of these ions in cells and tissues. Serum albumin also carries many compounds such as drugs, hormones, and fatty acids. Therefore, binding regime of a drug with albumin may affect the serum albumin level and a certain amount of calcium and magnesium in plasma. Also, the calcium and magnesium concentrations of blood influence the binding properties of all transported materials. Quinoxalines have a significant potential in pharmaceutical chemistry. In this study, we reported the synthesis and characterization of novel quinoxaline bridged bis(benzimidazolium) salts with trifluoromethyl substituents. New compounds were characterized by elemental analysis, H-1-NMR, C-13-NMR, and IR spectroscopy. The interactions of quinoxaline bridged bis(benzimidazolium) salts with BSA were investigated. The changes of the interactions with the presence of Ca2+ and Mg2+ were also studied. The binding constants in the presence of Ca2+ and Mg2+ are approximately 10(4) level. Additionally, the interactions between the optimized molecules and BSA were detailed with molecular docking methods. The highest interaction was detected for 2c with -8.33 kcal/mol binding affinity. The binding affinities of other molecules are listed as 2a > 2e > 2d > 2b. H-bonds were detected for all molecules.Öğe Synthesis, Characterization, and Screening Anticancer-Antibiofilm Activities of Theophylline Derivatives Containing CF3/OCF3 Moiety(Mdpi, 2025) Dusunceli, Serpil Demir; Coskun, Kubra Acikalin; Kaloglu, Murat; Ustun, Elvan; Caliskan, Reyhan; Tutar, YusufBackground: Theophylline, which is biologically important and found in tea, coffee, and cocoa beans, can be synthesized chemically or by direct extraction and concentration from natural sources. Theophylline derivatives have garnered attention in recent years for their potential therapeutic effects on Mycobacterium tuberculosis, antihistaminic, anti-inflammatory, and anticancer. Also, trifluoromethyl (CF3) group has also been widely used in drug and agrochemical design. Methods: In this study, a series of new theophylline derivatives containing substituted trifluoromethyl and trifluoromethoxy groups were synthesized. The structures of these new compounds were confirmed by NMR, FT-IR, and elemental analyses. Additionally, the anticancer activities of the molecules were analyzed against VEGFR-2, CYP P450, and estrogen receptor by molecular docking method. Furthermore, in vitro biological effects of the compounds were comprehensively evaluated in cancer (A549 and HeLa) and normal (BEAS-2B) cells. Cell viability was assessed by MTT assay, and selectivity index (SI) values were calculated to determine tumor-specific toxicity. Results: N(7)-substituted theophyllines were prepared by the reaction of 1,3-dimethyl-3,7-dihydro-1H-purine-2,6-dione (theophylline) and trifluoromethyl substituted benzyl halide compounds. The synthesized N(7)-substituted theophyllines were obtained as white powder in high yield. The structure of synthesized compounds was confirmed by various spectroscopic techniques such as 1H, 13C, 19F NMR, and FT-IR spectroscopy, and elemental analysis. The highest interaction was recorded as -5.69 kcal/mol for 3-CF3 substituted against VEGFR-2 structure while the best binding affinity was determined for 4-OCF3 substituted with -6.69 kcal/mol against Human Cytochrome P450 with in silico analysis. The in vitro anticancer activities of the molecules were also evaluated against A549 and HeLa cells, and displayed considerably higher cytotoxicity with 2-CF3, 3-CF3, and 4-CF3 substituted molecules in Hela and A549 cell line. To elucidate the molecular mechanism, apoptosis-related gene expression changes were analyzed by RT-qPCR in A549 and HeLa cells treated with compound 2-CF3. Significant upregulation of pro-apoptotic markers and downregulation of anti-apoptotic genes were observed. Consistently, ELISA-based quantification confirmed increased protein levels of Caspase-3, BAX, and Cytochrome C, and decreased BCL-2, validating the apoptotic mechanism at the protein level. Also, the antibacterial and antibiofilm activity details of the molecules were evaluated against DNA Gyrase, and SarA crystal structures by molecular docking method. The highest interaction was recorded as -5.56 kcal/mol for 2-CF3 substituted with H-bonds with Asn46, Val71, Asp73, and Thr165 against DNA Gyrase crystal structure while 3-CF3 substituted has the best binding affinity against SarA. The in vitro antimicrobial effects of the molecules were also evaluated. Conclusions: The synthesized molecules may provide insight into the development of potential therapeutic agents to the increasing antimicrobial resistance and biofilm-forming capacity of microorganisms. Additionally, compound 2-CF3 substituted exhibited promising and selective anticancer activity through apoptosis induction, supported by gene and protein level evidence.Öğe Synthesis, Characterization, Crystal Structure, and BSA-Binding Properties with the Presence of Ca2+, Mg2+, and Zn2+ Ions by N(7)-Substituted Theophyllines(Wiley-V C H Verlag Gmbh, 2025) Dusunceli, Serpil Demir; Kaloglu, Murat; Sahin, Onur; Ustun, ElvanTheophylline (1,3-dimethylxanthine) contains a fused imidazole-pyrimidine ring system with conjugated double bonds. It is a naturally occurring alkaloid that belonging to the xanthine family. Various substituted theophylline derivatives widely known as biologically active scaffolds. In this work, the N(7)-substituted theophylline compounds were synthesized and characterized by 13C-NMR, 1H NMR, elemental analysis, and FT-IR spectroscopy. The crystal structure of 1,3-dimethyl-7-[(3-methylphenyl)methyl]-2,3,6,7-tetrahydro-1H-purine-2,6-dione, 1b, was determined by single crystal X-ray diffraction analysis. The interactions of substituted theophylline type molecules with BSA were analyzed by the Stern-Volmer method and Stern-Volmer constants, rate constants, binding numbers, and binding constants of each molecule were determined. In addition, the interaction of BSA with the presence of Ca2+, Mg2+, and Zn2+ ions were investigated, and it was determined that the addition of metal ions decreased the binding values for all molecules except 1b. The details of the bindings detected for this study were also examined by the molecular docking method. The interactions of the N(7)-substituted theophylline compounds with DNA were analyzed by Benesi-Hildebrand method. The molecular docking method has also been used for the interactions of molecules against DNA.Öğe Synthesis, characterization, crystal structure, and catalytic activity of palladium PEPPSI type complexes(Elsevier, 2026) Dusunceli, Serpil Demir; Gunel, Hayrunnisa; Keser, Serhat; Ozdemir, Namik; Ozdemir, IsmailFour novel Pd-PEPPSI complexes of p-cyano functionalized N-heterocyclic carbenes (NHC) [PdBr2(NHC)(L)], where NHC = 1-(2,3,5,6-tetramethylbenzyl)-3-(4-cyanobenzyl)benzimidazole-2-ylidene, 1,3-bis(4-cyanobenzyl) benzimidazole-2-ylidene, or 1-(4-methylbenzyl)-3-(4-cyanobenzyl)benzimidazole-2-ylidene, and L = pyridine or 3-chloropyridine were prepared and characterized by elemental analysis, 1H and 13C NMR, and IR spectroscopy. The molecular structure of dibromo[(1-(2,3,5,6-tetramethylbenzyl)-3-(4-cyanobenzyl)benzimidazole-2-ylidene] pyridinepalladium(II) (2a) was determined by single-crystal X-ray diffraction analysis. The catalytic activity of the Pd(II) complexes for Suzuki and Heck cross-coupling reactions was investigated in water-based solvent mixtures. They were moderately active in the reaction of phenylboronic acid and aryl bromides. With 4-bromoacetophenone and 4-bromobenzaldehyde, the desired products were obtained in 95% and 86% yields, respectively, within 15 min at 80 degrees C using dibromo [1,3-bis(4-cyanobenzyl) benzimidazole-2-ylidene]pyridine palladium(II), 2bIn the coupling of styrene with 4-bromoacetophenone, the product was obtained in 89% yield after 5 h 80 degrees C using catalyst 2a. The antioxidant activities of the four compounds were also evaluated using ABTS, OH and DPPH radical scavenging assays.Öğe Theoretical analysis of frontier orbitals, electronic transitions, and global reactivity descriptors of M(CO)4L2 type metal carbonyl complexes: a DFT/TDDFT study(Springer/Plenum Publishers, 2019) Ustun, Elvan; Dusunceli, Serpil Demir; Ozdemir, IsmailMetal carbonyl complexes, which have been known as effective catalysts since early days, find use in many fields both directly and indirectly. Although the use of metal carbonyl complexes as bio-probe and protein labeling agent due to their unique spectroscopic properties is known, metal carbonyls have recently been used as storage and transport carriers of carbon monoxide. These developments have motivated the synthesis of new metal carbonyl complexes. Despite the difficulties in obtaining prediction for the molecular properties of organometallic compounds, DFT-based calculation programs have been able to gain insight into the structural/electronic properties of inorganic and organic molecules.In this study, structural, electronic, and reactivity properties of characterized molybdenum and tungsten carbonyl complexes with benzimidazole and imidazoline derivative ligands were investigated using DFT-based calculation program ORCA.Öğe Well-defined palladium N-heterocyclic carbene complexes bearing CF3 moiety: Synthesis, characterization, crystal structure, direct C4-arylation of 3,5-dimethylisoxazole and antioxidant activity(Elsevier Science Sa, 2026) Kalcik, Aysegul; Kaloglu, Nazan; Keser, Serhat; Sahin, Zarife Sibel; Dusunceli, Serpil DemirA series of palladium N-heterocyclic carbene (NHC) complexes including trans-[Pd(NHC)Br2L] (L = C5H5N, 3-ClC5H4N, and N-methylimidazole) and [Pd(NHC)2Br2] have been prepared from {1-(benzyl)-3-(3,5-(bis(tri-fluoromethyl)benzyl)benzimidazolium bromide}. The structures of these new compounds were confirmed by NMR, FT-IR, and elemental analyses. The crystal structures of the dibromo-[1-(benzyl)-3-(3,5-(bis(tri-fluoromethyl)benzyl)benzimidazole-2-ylidene]-(pyridine)-palladium(II) and dibromo-[1-(benzyl)-3-(3,5-(bis (trifluoromethyl)benzyl)benzimidazole-2-ylidene]-(N-methylimidazole)-palladium(II) were determined by single-crystal X-ray diffraction. Palladium complexes were developed as efficient pre-catalysts for direct C4-arylation of 3,5-dimethylisoxazole and aryl bromides. Biological efficiency of trans-[Pd(NHC)Br2L]was evaluated by antioxidant activities like ABTS, OH and DPPH radical scavenging activity assays.
