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Öğe Acetylphenyl-substituted imidazolium salts: synthesis, characterization, in silico studies and inhibitory properties against some metabolic enzymes(Springer, 2023) Demirci, Ozlem; Tezcan, Burcu; Demir, Yeliz; Taskin-Tok, Tugba; Gok, Yetkin; Aktas, Aydin; Guzel, BilgehanHerein, we present how to synthesize thirteen new 1-(4-acetylphenyl)-3-alkylimidazolium salts by reacting 4-(1-H-imidazol-1-yl)acetophenone with a variety of benzyl halides that contain either electron-donating or electron-withdrawing groups. The structures of the new imidazolium salts were conformed using different spectroscopic methods (H-1 NMR, C-13 NMR, F-19 NMR, and FTIR) and elemental analysis techniques. Furthermore, these compounds' the carbonic anhydrase (hCAs) and acetylcholinesterase (AChE) enzyme inhibition activities were investigated. They showed a highly potent inhibition effect toward AChE and hCAs with K-i values in the range of 8.30 & PLUSMN; 1.71 to 120.77 & PLUSMN; 8.61 nM for AChE, 16.97 & PLUSMN; 2.04 to 84.45 & PLUSMN; 13.78 nM for hCA I, and 14.09 & PLUSMN; 2.99 to 69.33 & PLUSMN; 17.35 nM for hCA II, respectively. Most of the synthesized imidazolium salts appeared to be more potent than the standard inhibitor of tacrine (TAC) against AChE and Acetazolamide (AZA) against CA. In the meantime, to prospect for potential synthesized imidazolium salt inhibitor(s) against AChE and hCAs, molecular docking and an ADMET-based approach were exerted.Öğe Antioxidant responses in Phanerochaete chrysosporium exposed to Astrazone Red FBL textile dye(Wiley, 2013) Demirci, Ozlem; Hamamci, Dilek AsmaInterest in environmental-pollutant-induced oxidative stress and knowledge of the interactions between reactive oxygen species and cellular systems have increased in toxicology and microbial ecology considerably in recent decades. These reactive oxidants are produced by a variety of environmental sources: ionizing radiations, ultraviolet light, redox cycling drugs, hyperoxia, ischemia and redox-active xenobiotics or during metabolism of environmental pollutants, such as heavy metals in mining industries, dyes in wastewater of textile industries, pesticides and polycyclic hydrocarbons, i.e. foreign materials. In this study, the effect of dye on the antioxidative defence system of Phanerochaete chrysosporium was investigated, and we showed the ability of Phanerochaete chrysosporium to antioxidative response and defence system exposed to Astrazone Red FBL. Catalase, glutathione reductase, glutathione s-transferase activities and level of glutathione decreased, depending on the period of growth in each exposure to low and high concentration group (20 and 50?ppm) compared with the control group. Copyright (c) 2012 John Wiley & Sons, Ltd.Öğe Effects of endosulfan, thiamethoxam, and indoxacarb in combination with atrazine on multi-biomarkers in Gammarus kischineffensis(Academic Press Inc Elsevier Science, 2018) Demirci, Ozlem; Guven, Kemal; Asma, Dilek; Ogut, Serdal; Ugurlu, PelinStudies addressing the toxicity of pesticides towards non-target organisms focus on the median lethal concentration and biochemical response of individual pesticides. However, when determining environmental risks, it is important to test the combined effects of pesticides, such as insecticides and herbicides, which are frequently used together in agricultural areas. Here we aimed to investigate the toxic effects of the combined use of the herbicide atrazine and the insecticides, endosulfan, indoxacarb, and thiamethoxam on Gammarus kischineffensis. To do this, we tested the activities of oxidative stress, detoxification, and neurotoxicity biomarkers. Compared to atrazine alone, we detected higher glutathione-S-transferase, catalase and superoxide dismutase activities (oxidative stress biomarkers) when atrazine was combined with either endosulfan or indoxacarb. However, higher IBR values were determined in organisms where pesticide mixtures were used according to individual use. Based on these results, mixtures of atrazine and other pesticides may cause synergistic effects and may be evidence of increased toxicity and oxidative stress.Öğe Evaluation of the biochemical effects of an acetamiprid-based insecticide on a non-target species,Gambusia holbrooki(Wiley, 2020) Demirci, Ozlem; Gungordu, AbbasThe toxic effects of an acetamiprid-based insecticide (ABI) onGambusia holbrookiwere evaluated after 24 and 96-h exposure periods. The 24 and 96-h median lethal concentration (LC50) values of ABI were determined as 75.9 and 42.2 mg/L active ingredient (AI)/L, respectively. In addition, the activity of five biochemical marker enzymes, including glutathione S-transferase (GST), glutathione reductase (GR), carboxylesterase (CaE), lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) was measured after 24 and 96-h exposure to three different concentrations of the ABI to evaluate its sublethal effects. The acetamiprid concentrations in the exposure media were measured using liquid chromatography-tandem mass spectrometry. Our results showed that GST and LDH activities were increased and there were concentration-dependent changes in the integrated biomarker response (IBR) indexes after 24-h ABI exposure. However, the examined biomarkers were not useful for examining the effects of the ABI exposure for 96-h exposure periods, even at the highest concentration.Öğe Fluorinated benzimidazolium salts: Synthesis, characterization, molecular docking studies and inhibitory properties against some metabolic enzymes(Elsevier Science Sa, 2023) Zengin, Ramazan; Gok, Yetkin; Demir, Yeliz; Sen, Betul; Taskin-Tok, Tugba; Aktas, Aydin; Demirci, OzlemHere, a number of symmetric and unsymmetric N-heterocyclic carbene (NHC) precursors based on benzimidazol-2-ylidene are synthesized. The N-benzyl substituent in these compounds has an electron-withdrawing group (F) at the para position. The structure of these compounds was characterized using elemental analysis and various spectroscopic methods (FTIR and NMR). The molecular and crystal structures of compound 1f and compound 1h were unambiguously elucidated through single-crystal X-ray diffraction analysis. According to the X-ray studies, compound 1f exhibits the formation of a U-shaped molecule whereas compound 1h has a Z-shape formation. In addition, the enzyme inhibition activities of these compounds were investigated against acetylcholinesterase (AChE) and carbonic anhydrases (hCAs). They showed a highly potent inhibition effect on AChE and hCAs (Ki values are in the range of 14.84 +/- 1.91 to 174.80 +/- 23.60 nM for AChE, 22.41 +/- 1.93 to 188.67 +/- 27.05 nM for hCA I and 35.29 +/- 7.21 to 136.55 +/- 17.61 nM for hCA II). These results may contribute to the design and development of new drug candidates, particularly for treatment of some widespread disorders displayed in the world including Alzheimer's disease and glaucoma.Öğe PEPPSI type Pd(II)NHC complexes bearing chloro-/fluorobenzyl group: Synthesis, characterization, crystal structures, ?-glycosidase and acetylcholinesterase inhibitory properties(Pergamon-Elsevier Science Ltd, 2021) Bal, Selma; Demirci, Ozlem; Sen, Betul; Taslimi, Parham; Aktas, Aydin; Gok, Yetkin; Aygun, MuhittinThis work reported the synthesis of a new PEPPSI (Pyridine Enhanced Precatalyst Preparation, Stabilization and Initiation) type Pd(II)N-heterocyclic carbene (NHC) complexes bearing halo-benzyl (4-florobenzyl and 2-chloro-4-florobenzyl) group. These new complexes were synthesized from the florobenzyl / chlorofluorobenzyl substituted benzimidazolium salts, PdCl2 and pyridine. Characterizations of all the synthesized complexes were done using elemental analysis, H-1 NMR, C-13 NMR and FT-IR spectroscopy techniques. The molecular and crystal structures of the new PEPPSI type Pd(II)NHC complexes were determined by single-crystal X-ray diffraction method. X-ray studies show that molecular structures of three complexes comprise a palladium(II) atom with a slightly distorted square-planar coordination environment. These synthesized salts were found to be effective inhibitors for the alpha-glycosidase, and acetylcholinesterase (AChE) enzyme with K-i values in the range of 27.36 +/- 5.06-124.88 +/- 18.05 mu M for alpha-glycosidase, and 0.78 +/- 0.11-4.34 +/- 1.02 mu M for AChE, respectively. The significant group of drugs currently utilized for the therapy of Alzheimer's disease (AD) is acetylcholinesterase/cholinesterase inhibitor compounds. The first cholinesterase inhibitor licensed for symptomatic therapy of AD was tacrine. Inhibition acts of alpha-glycosidase enzyme by inhibitors tend to slow the breakdown and release of sugar molecules into the bloodstream and can be utilized as therapeutic factors in the therapy of obesity and diabetes. (C) 2021 Elsevier Ltd. All rights reserved.Öğe Silver N-heterocyclic carbene complexes bearing fluorinated benzyl group: Synthesis, characterization, crystal structure, computational studies, and inhibitory properties against some metabolic enzymes(Wiley, 2021) Bal, Selma; Demirci, Ozlem; Sen, Betul; Taskin Tok, Tugba; Taslimi, Parham; Aktas, Aydin; Gok, YetkinA series of the silver N-heterocyclic carbene (NHC) complexes have been synthesized from the reactions between benzimidazolium salts bearing fluorinated benzyl group and Ag2O via the deprotonation method. All Ag(I)NHC complexes were characterized by known spectroscopic techniques (H-1 nuclear magnetic resonance [NMR], C-13 NMR, and Fourier transform infrared [FT-IR]) and elemental analysis. The molecular structures of the two complexes were unambiguously elucidated through single-crystal X-ray diffraction analysis. Namely, X-ray studies show that the coordination geometry around the Ag(I) atom in the case of complex 2c is revealed to be almost linear with C-Ag-Cl angle, whereas in complex 2e, it appears as a nonlinear structure. The inhibitory profiles of these new complexes are investigated on some metabolic enzymes. Representatively, the most potent complex against human carbonic anhydrase isoenzymes I and II (hCAs I and II), 2d, was 1.8 times more potent than standard inhibitor acetazolamide against hCAs I and II. On the other hand, complexes 2c and 2b as most potent compounds against both cholinesterase enzymes was around 5 and 1.6 times more potent than tacrine against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), respectively. The most active alpha-glucosidase inhibitor 2d had similar activity to acarbose as a standard inhibitor. Furthermore, it confirms its in vitro studies as a result of molecular docking studies for each enzyme with (i) binding energy and inhibition constant values and (ii) the definition of the best conformation and nonbonding interactions of the related complexes (2b, 2c, and 2d) against the different target proteins.Öğe Synthesis, characterization, crystal structure, ?-glycosidase, and acetylcholinesterase inhibitory properties of 1,3-disubstituted benzimidazolium salts(Wiley-V C H Verlag Gmbh, 2021) Bal, Selma; Demirci, Ozlem; Sen, Betul; Taslimi, Parham; Aktas, Aydin; Gok, Yetkin; Aygun, MuhittinChloro-/fluorobenzyl-substituted benzimidazolium salts were synthesized from the reaction of 4-fluorobenzyl/2-chloro-4-fluorobenzyl-substituted benzimidazole and chlorinated aromatic hydrocarbons. They were characterized using various spectroscopic techniques (Fourier-transform infrared and nuclear magnetic resonance) and elemental analysis. In addition, the crystal structures of the complexes 1a -d and 2b were determined by single-crystal X-ray diffraction methods. These compounds were crystallized in the triclinic crystal system with a P-1 space group. The crystal packing of all complexes is dominated by O-HMIDLINE HORIZONTAL ELLIPSISCl hydrogen bonds, which link the water molecules and chloride anions, forming a chloride-water tetrameric cluster. These synthesized salts were found to be effective inhibitors for alpha-glycosidase and acetylcholinesterase (AChE), with K-i values ranging from 45.77 +/- 6.83 to 102.61 +/- 11.56 mu M for alpha-glycosidase and 0.94 +/- 0.14 to 10.24 +/- 1.58 mu M for AChE. AChE converts acetylcholine into choline and acetic acid, thus causing the return of a cholinergic neuron to its resting state. Discovering AChE and alpha-glycosidase inhibitors is one of the important ways to develop new drugs for the treatment of Alzheimer's disease and diabetes.
