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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 Biological Activities of NHC-Pd(II) Complexes Based on Benzimidazolylidene N-heterocyclic Carbene (NHC) Ligands Bearing Aryl Substituents(Mdpi, 2020) Al Nasr, Ibrahim; Touj, Nedra; Koko, Waleed; Khan, Tariq; Ozdemir, Ismail; Yasar, Sedat; Hamdi, NaceurN-heterocyclic carbene (NHC) precursors (2a-i), their pyridine-enhanced precatalyst preparation stabilization and initiation (PEPPSI)-themed palladium N-heterocyclic carbene complexes (3a-i) and palladium N-heterocyclic triphenylphosphines complexes (4a-i) were synthesized and characterized by elemental analysis and H-1 NMR, C-13 NMR, IR, and LC-MS spectroscopic techniques. The (NHC)Pd(II) complexes 3-4 were tested against MCF7 and MDA-MB-231 cancer cells, Escherichia coli, methicillin-resistant Staphylococcus aureus (MRSA), Candida albicans microorganisms, Leishmania major promastigotes and amastigotes, Toxoplasma gondii parasites, and Vero cells in vitro. The biological assays indicated that all compounds are highly active against cancer cells, with an IC50 < 1.5 mu g mL(-1). Eight compounds proved antibacterial and antileishmanial activities, while only three compounds had strong antifungal activities against C. albicans. In our conclusion, compounds 3 (b, f, g, and h) and 4b are the most suitable drug candidates for anticancer, antimicrobial, and antiparasitical.Öğe Biological determination, molecular docking and Hirshfeld surface analysis of rhoduim(I)-N-heterocyclic carbene complex: Synthesis, crystal structure, DFT calculations, optical and non linear optical properties(Elsevier Science Sa, 2023) Zouaghi, Mohamed Oussama; Amri, Nasser; Hassen, Sabri; Arfaoui, Youssef; Ozdemir, Namik; Ozdemir, Ismail; Hamdi, NaceurThe synthesis and characterization of 1-(isobutyl)-3-(2.3.5.6 tetramethylbenzyl)-5.6-dimethylbenzimidazolium chloride and its N-functionalized Rhodium(I) N-heterocyclic carbene complex have been described. The ligand 2 and the complex 3 were characterized by IR, 1H NMR and 13C NMR spectroscopy, DART-TOF mass spec-trometry and elemental analysis. The coordination mode of the complex was confirmed by single crystal XRD analysis. We performed a comparative theoretical study in order to investigate the impact of the iridium on the optoelectronic and non-linear optical properties of the complex. The M06-2X functional with the mixed basis set (6-31G(d): def2tzvp) was found the best method for optimizing the studied complex since it displayed close geometric data to the experiment. As a novelty in this work, iridium was found to be a performer for NLO ap-plications over rhodium. This Rh(I)-N-Heterocyclic carbenes (NHC) showed good catalytic performance for the hydrosilylation of acetophenone derivatives with triethylsilane at 80 C for 1 h by using 1 mol % of this complex. The cytotoxic properties of the rhodium(I)-NHC complex have been assessed against MCF7 and MDA-MB-231 cancer cells and the complex show interest activity. The in vitro antibacterial activity of this complex were also investigated against Micrococcus luteus LB 14110, Listeria monocytogenes ATCC 19117, Salmonella Typhimurium ATCC 14028, Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa and Candida albicans microorganisms indicated their significant biological potential. Additionally, the antioxidant activity of the same complex has been analyzed with DPPH center dot free radical through spectrophotometric method and the result inferred them as an antioxidant. The potential biological activities were investigated by using molecular docking analysis.Öğe Bridged NHC-Pd(II) complexes: Synthesis, DFT calculations, molecular docking, and investigation of catalytic and biological activities(Elsevier Science Sa, 2024) Firat, Tuba; Bugday, Nesrin; Yasar, Seyma; Boulebd, Houssem; Mansour, Lamjed; Koko, Waleed S.; Hamdi, NaceurSix palladium(II) ( 3a -f ) complexes of the type [Pd 2 ( mu-Cl) 2 (NHC)] were prepared by transmetallation of the corresponding Ag-NHC and [PdCl 2 (CH 3 CN) 2 ] complexes, and their structures were successfully characterised by 1 H NMR, 13 C NMR, HRMS, FTIR and elemental analysis. Density functional theory (DFT) calculations were also realised for the complexes. The prepared complexes were assessed for their catalytic activity in the C -H arylation of 2-isobuthylthiazole as well as for their biological activities. As results, these complexes were found to be potent catalysts in the creation of C5-arylated 2-isobuthylthiazole derivatives via C -H bond activation reaction. Furthermore, biological activity analysis revealed that complex 3a exhibits high cytotoxicity towards both human colon carcinoma cell lines (HCT-116) and hepatocellular carcinoma cell lines (HepG-2) with IC 50 values of 4.2 and 9.3 mu MmL -1 , respectively. Complex 3b also showed antioxidant activity comparable to that of BHT through DPPH and ABTS assays. Both complexes 3d and 3f also showed significant inhibitory activity towards the AChE enzyme with IC 50 values of 5.06 and 2.52 mu MmL -1 , respectively. Finally, all complexes showed excellent antiparasitic activity, with 3b exhibiting strong antileishmanial activity against both L. major promastigotes and amastigotes. The interaction between the most cytotoxic complexes and DNA, envisaged as a potential mechanism of toxicity, was explored by means of docking studies. In summary, these prepared complexes have the potential to serve as potent catalysts for the synthesis of arylated 2-isobutylthiazole and biologically active agents, paving the way for numerous prospects in the fields of medicinal chemistry and organic synthesis.Öğe The direct C(sp2)-H functionalization and coupling of aromatic N-heterocycles with (hetero)aryl bromides by [PdX2(imidazolidin-2-ylidene)(Py)] catalysts(Elsevier Science Sa, 2021) Kaloglu, Murat; Slimani, Ichraf; Ozdemir, Namik; Gurbuz, Nevin; Hamdi, Naceur; Ozdemir, IsmailIn this study, a series of air- and moisture-stable imidazolidin-2-ylidene-based new palladium complexes with the general formula [PdX2(NHC)(Py)] were synthesized (NHC = N-heterocyclic carbene, Py = pyridine, X = Cl or I). The structures of the palladium complexes were characterized by different techniques such as H-1 NMR, C-13 NMR, FT-IR spectroscopy and elemental analysis. The more detailed structural characterization of one of the palladium complex was determined by single-crystal X-ray diffraction study. The catalytic activities of all palladium complexes were tested in the direct arylation of five-membered aromatic N-heterocycles such as 3,5-dimethylisoxazole and 1-methyl-1H-pyrrole-2-carboxaldehyde with (hetero)aryl bromides in presence of 1 mol% catalyst loading at 120 degrees C. Desired products were obtained in moderate to good yields. (C) 2021 Elsevier B.V. All rights reserved.Öğe An efficient (NHC) Copper (I)-catalyst for azide-alkyne cycloaddition reactions for the synthesis of 1,2,3-trisubstituted triazoles: Click chemistry(Elsevier Science Sa, 2017) Touj, Nedra; Ozdemir, Ismail; Yasar, Sedat; Hamdi, NaceurIn this study a series of new benzimidazolium salts (2a-c) were synthesized from the reaction of 5,6-dimethyl-1-(alkylbenzyl)-1H-benzo[d] imidazole with various alkyl halides. These salts were used to synthesize cupper N-heterocyclic carbene (Cu-NHC) complexes 3-4. The obtained (NHC) Copper (I) complexes 3-4 were characterized by FT-IR, NMR (H-1 and C-13) spectroscopic methods, mass spectrometry (EI-MS and HRMS) and elemental analysis. These novel cupper complexes 3-4 were used as a catalyst for alkyne - azide cycloaddition (CuAAC) reaction. Several triazoles 7 have been synthesized. This catalytic system fulfils the requirements of click chemistry with its mild and convenient conditions, notably in water at room temperature with low catalyst loading and simple isolation with no purification step. (C) 2017 Elsevier B.V. All rights reserved.Öğe An efficient palladium catalyzed mizoroki-heck cross-coupling in water: synthesis, characterization and catalytic activities(Pergamon-Elsevier Science Ltd, 2024) Bensalah, Donia; Mansour, Lamjed; Sauthier, Mathieu; Gurbuz, Nevin; Ozdemir, Ismail; Gatri, Rafik; Hamdi, NaceurA series of new palladium complexes known as PEPPSI-type complexes 3 were successfully synthesized by reacting benzimidazolium salts 2a -e , potassium carbonate (K 2 CO 3 ), and palladium chloride (PdCl 2 ) in pyridine for 16 h at 80 degrees C. Both the benzimidazolium salts 2a -e and the resulting complexes 3 were characterized through spectroscopic data and elemental analysis. The Mizoroki-Heck coupling reaction, catalyzed by the homogeneous Pd, was effectively carried out in water without the need for any additional substances under aerobic conditions. The optimization of various key reaction parameters was performed to enhance the yield of the desired cross coupling product. The catalytic performance of these complexes in a catalytic system containing palladium complexes 3a , Et 3 N, and H 2 O was evaluated in the Mizoroki-Heck coupling reaction. The PEPPSI-type palladium complex 3a /Et 3 N/H 2 O/98 degrees C catalyst system exhibited high activity, with a turnover frequency (TOF) ranging from 12 to 14 /hour towards achieving the excellent yield of the Mizoroki-Heck coupling products for a wide range of electron withdrawing as well as electron donating aryl bromide and chlorides in shortest reaction time.Öğe Evaluation of Ruthenium(II) N-Heterocyclic Carbene Complexes as Enzymatic Inhibitory Agents with Antioxidant, Antimicrobial, Antiparasitical and Antiproliferative Activity(Mdpi, 2023) Al Nasr, Ibrahim S. S.; Koko, Waleed S. S.; Khan, Tariq A. A.; Gurbuz, Nevin; Ozdemir, Ismail; Hamdi, NaceurA series of [RuCl2(p-cymene)(NHC)] complexes were obtained by reacting [RuCl2(p-cymene)]2 with in situ generated Ag-N-heterocyclic carbene (NHC) complexes. The structure of the obtained complexes was determined by the appropriate spectroscopy and elemental analysis. In addition, we evaluated the biological activities of these compounds as antienzymatic, antioxidant, antibacterial, anticancer, and antiparasitic agents. The results revealed that complexes 3b and 3d were the most potent inhibitors against AchE with IC50 values of 2.52 and 5.06 mu M mL(-1). Additionally, 3d proved very good antimicrobial activity against all examined microorganisms with IZ (inhibition zone) over 25 mm and MIC (minimum inhibitory concentration) < 4 mu M. Additionally, the ligand 2a and its corresponding ruthenium (II) complex 3a had good cytotoxic activity against both cancer cells HCT-116 and HepG-2, with IC50 values of (7.76 and 11.76) and (4.12 and 9.21) mu M mL(-1), respectively. Evaluation of the antiparasitic activity of these complexes against Leishmania major promastigotes and Toxoplasma gondii showed that ruthenium complexes were more potent than the free ligand, with an IC50 values less than 1.5 mu M mL(-1). However, 3d was found the best one with SI (selectivity index) values greater than 5 so it seems to be the best candidate for antileishmanial drug discovery program, and much future research are recommended for mode of action and in vivo evaluation. In general, Ru-NHC complexes are the most effective against L. major promastigotes.Öğe Experimental and quantum mechanical investigation on two N-heterocyclic carbene palladium complexes(Taylor & Francis Ltd, 2021) Ozdemir, Namik; Touj, Nedra; Yasar, Sedat; Hamdi, Naceur; Ozdemir, IsmailTwo palladium complexes bearing different ligands such as N-heterocyclic carbene (NHC), pyridine and phosphines were synthesized and characterized by FT-IR spectroscopy, X-ray crystallography and quantum-chemical computations. DFT calculations have been performed at HSEh1PBE/SDD level of theory. Intermolecular interactions have been studied through two-dimensional fingerprint plots based on Hirshfeld surface analysis. Structural parameters and spectroscopic properties of the complexes are well interpreted by DFT and TD-DFT calculations.Öğe From Synthesis to Biological Impact of Ru (II) Complexes: Preparation, Characterization, Antimicrobial, Antioxidant scavenging and Enzymatic inhibitory activities(Natl Inform & Document Centre, 2023) Amri, Nasser; Mukhrish, Yousef E.; Gatri, Rafik; Gurbuz, Nevin; Ozdemir, Ismail; Dridi, Khaireddine; Hamdi, NaceurThe reaction of [RuCl2(p-cymene)]2 with in situ prepared Ag-N-heterocyclic carbene (NHC) complexes yields a series of [RuCl2(p-cymene) (NHC)] complexes 3. The structures of complexes were established by appropriate spectroscopic methods and elemental analyses. The biological activities of the synthesized ligands and their Ru (II) complexes as acetylcholinesterase, antimicrobial, and antioxidant agents were evaluated. The lowest MICs values were obtained with the two complexes 3b and 3d. The enzymatic inhibitory investigation against acetylcholinesterase (AChE) and tyrosinase (TyrE), showed that the two complexes 3b and 3d are the most potent inhibitors against (AchE) with an IC50 of 2.52 and 5.06 & mu;g mL-1 respectively, and against (TyrE) with an IC50 of 19.88 and 24.95 & mu;g mL-1 respectively. Additionally, DPPH (2,2-diphenyl-1-picrylhydrazyl) has been tested for its ability to scavenge hydrogen peroxide and free radicals. According to our results, these compounds exhibitÖğe Highly Efficient Single A3-Coupling (Aldehyde-Amine-Alkyne) Reaction Catalyzed by Air Stable Silver-(N-Heterocyclic Carbene) Complexes: Synthesis and Characterization(Taylor & Francis Ltd, 2022) Hamdi, Naceur; Mnasri, Aziza; S. Al Nasr, Ibrahim; S. Koko, Waleed; Khan, Tariq A.; Ozdemir, Ismail; Gurbuz, NevinThe interaction of N,N-disubstituted benzimidazolium salts 2a-e with Ag2O formed new silver-(N-heterocyclic carbene) complexes 3a-e. Structural characterization of silver-(N-heterocyclic carbene) complexes was conducted by using NMR, FT-IR and elemental analysis. Preliminary catalytic studies using all the silver complexes 3a-e were performed on three-component coupling reaction of a series of aldehydes with alkynes and amines was demonstrated. Most of these reactions led to formation of the expected propargylamines in good conversions using low amounts catalyst and obviating both the use of purified reagents as employ of a glovebox. Complexes 3a and 3c exhibited good catalytic activities under neat conditions. The silver complexes 3a-e showed luminescence properties in CH3CN at room temperature.Öğe Novel N-Heterocyclic Carbene Silver(I) Complexes: Synthesis, Structural Characterization, Antimicrobial and Cytotoxicity Potential Studies(Soc Brasileira Quimica, 2020) Slimani, Ichraf; Chakchouk-Mtibaa, Ahlem; Mellouli, Lotfi; Mansour, Lamjed; Ozdemir, Ismail; Gurbuz, Nevin; Hamdi, NaceurIn this study, a series of unsymmetrical N,N-disubstituted benzimidazolium salts were synthesized as N-heterocyclic carbene (NHC) (2a-2j) and their Ag-I complexes. Their structures were characterized by elemental analyses, H-1 and C-13 nuclear magnetic resonance (NMR) and infrared (IR) spectroscopy techniques. Further, both the salts and their silver(I)-NHC complexes have been evaluated for their potential antibacterial properties against a panel of bacterial strains namely, Micrococcus luteus, Listeria monocytogenes, Salmonella Typhimurium, Staphylococcus aureus and Pseudomonas aeruginosa. The results show that silver complexes are effective against Salmonella Typhimurium, Listeria monocytogenes, and Micrococcus luteus with moderate to high activity, and their minimum inhibitory concentrations ranging from 0.0034 to 1.26 mg mL(-1). In addition, the benzimidazoles salts 2a-2j and silver-NHC complexes 3a-3j were screened for their antitumor activity. Complex 3e exhibited the highest antitumor effect with half-maximal inhibitory concentration (IC50) value of 4.2 mu g mL(-1) against MCF-7.Öğe Palladium PEPPSI complexes: Synthesis and catalytic activity on the Suzuki-Miyaura coupling reactions for aryl bromides at room temperature in aqueous media(Elsevier Science Sa, 2018) Touj, Nedra; Gurbuz, Nevin; Hamdi, Naceur; Yasar, Sedat; Ozdemir, IsmailA new series of palladium N-heterocyclic carbene complexes having methoxyethyl on the side chain (3a-d, 4a-e) have been synthesized and fully characterized by NMR, HRMS and IR. Next, the palladium-NHC-PEPPSI complexes 3a-e and 4a-e were used as catalyst in Suzuki-Miyaura coupling reactions were investigated for aryl bromides at room temperature in aqueous media. 3a-d and 4a-e complexes showed good catalytic activity for electron-donating or electron-drawing aryl bromides with arylboronic acid. Complex 4b exhibited higher activity compared to other analogues due to bearing more electronically donating NHC ligands. (C) 2018 Elsevier B.V. All rights reserved.Öğe Preparation and characterization of PEPPSI-palladium N-heterocyclic carbene complexes using benzimidazolium salts catalyzed Suzuki-Miyaura cross coupling reaction and their antitumor and antimicrobial activities(Taylor & Francis Ltd, 2019) Boubakri, Lamia; Dridi, Khaireddine; Al-Ayed, Abdullah Sulaiman; Ozdemir, Ismail; Yasar, Sedat; Hamdi, NaceurNew palladium complexes were efficiently synthesized from the reaction of benzimidazolium salts 2a-e, potassium carbonate (K2CO3) and palladium chloride (PdCl2) in pyridine (for 3a-e). The catalytic activity of these complexes in a catalytic system including palladium complexes and K2CO3 in DMF-H2O was evaluated in Suzuki-Miyaura cross-coupling reactions of aryl bromides and chlorides with phenylboronic acid. Our novel complexes show excellent catalytic activities with high turnover numbers (TON) and high turnover frequencies (TOF) (e.g. for the Suzuki-Miyaura reaction: TON up to 370 and TOF up to 123.3 h(-1)). Both benzimidazolium salts 2a-e and complexes 3 have been characterized using spectroscopic data and elemental analysis. The antimicrobial activity of the N-heterocyclic carbene palladium complexes 3a-e varies with the nature of the ligands. Also, the IC50 values of both, complexes (3a-e) and benzimidazoles 2a-e, have been determined. In addition, the new palladium complexes were screened for their antitumor activity. Complexes 3e and 3d exhibited the highest antitumor effect with IC50 values 6.85 mu g/mL against MCF-7 and 10.75 mu g/mL against T47D, respectively. [GRAPHICS] .Öğe Rhodium(I) complexes with N-heterocyclic carbene ligands: synthesis, biological properties and catalytic activity in the hydrosilylation of aromatic ketones(Taylor & Francis Ltd, 2021) Hamdi, Naceur; Slimani, Ichraf; Mansour, Lamjed; Alresheedi, Faisal; Ozdemir, Ismail; Gurbuz, NevinNew rhodium(I) N-heterocyclic carbene (NHC) complexes 3a-f were synthesized in good yields by the reactions of rhodium dimer [Rh(OMe)(cycloocta-1,5-diene:COD)](2) with benzimidazolium salts 2a-f in tetrahydrofuran. All the complexes were characterized by IR, H-1-NMR, and C-13-NMR spectroscopy, DART-TOF mass spectrometry (for 3b, 3d and 3f) and elemental analysis. All complexes were used as catalysts in the hydrosilylation of acetophenone derivatives with triethylsilane at 80 degrees C for 1 h. These Rh(I) NHC showed good catalytic performance for the hydrosilylation of acetophenone derivatives by using 1 mol % of the rhodium complexes. In addition the new rhodium(I) NHC complexes were tested against MCF7 and MDA-MB-231 cancer cells, Micrococcus luteus LB 14110, Listeria monocytogenes ATCC 19117, Salmonella Typhimurium ATCC 14028, Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa and Candida albicans microorganisms. The synthesized rhodium(I) NHC complex 3f was found the most active against MCF7 cancer cells (half-growth inhibition concentration (IC50) = 0.3 mu g mL(-1)), as well as the most potent antimicrobial against L. monocytogenes ATCC 19117 (inhibition zone (IZ) = 29 mm). Moreover, the antioxidant activity determination of these complexes was studied with the DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) and compared with gallic acid and butylated hydroxytoluene.Öğe Rhodium(i) N-heterocyclic carbene complexes: synthesis and cytotoxic properties(Royal Soc Chemistry, 2021) Slimani, Ichraf; Sahin-Bolukbasi, Serap; Ulu, Mustafa; Evren, Enes; Gurbuz, Nevin; Ozdemir, Ilknur; Hamdi, NaceurRhodium(i) complexes bearing N-heterocyclic carbene (NHC) ligands have been widely used in catalytic chemistry, but there are very few reports of biological properties of these types of complexes. A series of benzimidazolium salts and their [RhCl(NHC)(COD)] complexes were synthesized. The obtained complexes were synthesized and characterized by elemental analysis, FT-IR, H-1 and C-13 NMR. All compounds were screened for in vitro cytotoxic activities against a panel of human cancer cells (HT-29 colon, Ishikawa endometrial, and U-87 glioblastoma) using the MTT assay for 48 h of incubation time. Mouse fibroblast cells (L-929) were used as healthy cells. Complexes had exhibited significantly higher cytotoxic activity towards cancer cells than their ligands and complex 2b showed the most selective cytotoxic activity against HT-29 cancer cells (SI;7.05) and Ishikawa cancer cells (SI; more than 9.8). The complexes showed strong in vitro cytotoxic activity against cancer cells, with IC50 values of lower than 10 mu M (except 2a against HT-29 (12.8 mu M) and 2b against U-87 (11.1 mu M)). All complexes (2a-d) showed the highest in vitro cytotoxic activity against Ishikawa endometrial cancer cells with IC50 values of 2.93 +/- 0.06, <1, 2.60 +/- 0.05, and 2.85 +/- 0.06 mu M, respectively. Complexes were found to be highly cytotoxic against HT-29, Ishikawa, and U-87 cancer cells compared to the anticancer agents, cisplatin and 5-FU.Öğe Silver-N-heterocyclic carbene complexes-catalyzed multicomponent reactions: Synthesis, spectroscopic characterization, density functional theory calculations, and antibacterial study(Wiley-V C H Verlag Gmbh, 2021) Mnasri, Aziza; Mejri, Amal; Al-Hazmy, Sadok M.; Arfaoui, Youssef; Ozdemir, Ismail; Gurbuz, Nevin; Hamdi, NaceurNowadays, silver-N-heterocyclic carbene (silver-NHCs) complexes are widely used in medicinal chemistry due to their low toxic nature toward humans. Due to the success of silver-NHCs in medicinal applications, interest in these compounds is rapidly increasing. Therefore, the interaction of N,N-disubstituted benzimidazolium salts with Ag2O in dichloromethane to prepare novel Ag(I)-NHCs complexes was carried out at room temperature for 120 h in the absence of light. The obtained complexes were identified and characterized by H-1 and C-13 nuclear magnetic resonance, Fourier-transform infrared, UV-Vis, and elemental analysis techniques. Then, the silver complexes were applied for three-component coupling reactions of aldehydes, amines, and alkynes. The effect of changing the alkyl substituent on the NHCs ligand on the catalytic performance was investigated. In addition, it has been found that the complexes are antimicrobially active and show higher activity than the free ligand. The silver-carbene complexes showed antimicrobial activity against specified microorganisms with MIC values between 0.24 and 62.5 mu g/ml. These results showed that the silver-NHC complexes exhibit an effective antimicrobial activity against bacterial and fungal strains. A density functional theory calculation study was performed to identify the stability of the obtained complexes. All geometries were optimized employing an effective core potential basis, such as LANL2DZ for the Ag atom and 6-311+G(d,p) for all the other atoms in the gas phase. Electrostatic potential surfaces and LUMO-HOMO energy were computed. Transition energies and excited-state structures were obtained from the time-dependent density functional theory calculations.Öğe Sonogashira cross-coupling reaction catalysed by mixed NHC-Pd-PPh3 complexes under copper free conditions(Elsevier Science Sa, 2018) Touj, Nedra; Yasar, Sedat; Ozdemir, Namik; Hamdi, Naceur; Ozdemir, IsmailMixed NHC-Pd-PPh3 complexes with a methoxyethyl-substituted N-heterocyclic carbene ( NHC) were synthesised and characterised by NMR, HRMS, elemental analysis and X-ray crystallography for complex 3b. These complexes were applied to Sonogashira cross-coupling reactions between aryl bromides and phenylacetylene in DMF at 80 degrees C. All palladium complexes were stable and showed high catalytic activity in Sonogashira reactions at low catalyst loading and ambient reaction conditions. (c) 2018 Elsevier B.V. All rights reserved.Öğe Synthesis and Investigation of Antimicrobial, Antioxidant, Enzymatic Inhibitory, and Antiproliferative Activities of Ruthenium (II) Complexes Bearing Benzimidazole-Based N-Heterocyclic Carbene (NHC) Ligands(Taylor & Francis Ltd, 2022) Hamdi, Naceur; Mansour, Lamjed; Al-Tamimi, Jameel; Al-Hazmy, Sadeq M.; Gurbuz, Nevin; Ozdemir, IsmailThe benzimidazolium salts 2a-d were synthesized by quaternization of 1-(4-tet-buthylbenzyl) benzimidazole, with the corresponding benzysl bromide. The reactions were carried out in dimethylformamide at 70 degrees C for 48 h. Therefore, Ag2O and benzimidazolium salts 2a-d were reacted in dichloromethane at room temperature under dark and Ag(I)-NHC complex 3 was obtained in very good yields. The Ru(II)-NHC complexes (4a-d) were synthesized via transmetalation reaction from 3a-d. The structures of the obtained compounds were characterized by different spectroscopic techniques such as H-1 and C-13 NMR, elemental analysis, and melting point detection. The lowest MICs values were obtained with the two complexes 4b and 4d. Enzymatic inhibitory investigation against acetylcholinesterase (AChE) and tyrosinase (TyrE), showed that the two complexes 4b and 4d are the most potent inhibitors against (AchE) with an IC50 of 2.52 and 5.06 mu g mL(-1) respectively, and against (TyrE) with an IC50 of 19.88 and 24.95 mu g mL(-1) respectively. Screening of the selected N-Heterocyclic carbene (NHC) ligands (2a-2d) and their respective ruthenium (II) complexes (4a-4d) against colon carcinoma cells lines (HCT-116) and hepatocellular carcinoma cells lines (HepG-2). Furthermore, compounds 2c, 2d, 4b were showed weak cytotoxic action with IC50 ranging from 13.38 to 18.33 mu g in human colon carcinoma cancer cell lines and from 14.36 to 18.45 mu g in hepatocellular carcinoma cells lines.Öğe Synthesis of novel Ag(I)-N-heterocyclic carbene complexes soluble in both water and dichloromethane and their antimicrobial studies(Taylor & Francis Ltd, 2019) Boubakri, Lamia; Dridi, Khaireddine; Al-Ayed, Abdullah Sulaiman; Ozdemir, I.; Yasar, S.; Hamdi, NaceurThe interaction of the benzimidazolium salt with Ag2O in dichloromethane to prepare novel Ag(I)-N-heterocyclic carbene complexes has been carried out at room temperature for 48 h in the absence of light. The obtained complexes were identified and characterized by H-1 and C-13 NMR, FT-IR and elemental analysis techniques. In addition, it has been found that some of the complexes are antimicrobially active and show higher activity than the free ligand. Probably metal chelation affects significantly the antimicrobial behavior of the ligands. The minimum inhibitory concentration of the complexes was determined. The results indicated that these complexes exhibit antimicrobial activity.
