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51.
Serkan Levent Ulviye Acar Çevik Begüm Nurpelin Sağlık Özgür Devrim Can Ümide Demir Özkay 《Phosphorus, sulfur, and silicon and the related elements》2017,192(4):469-474
The present study was undertaken to synthesize some novel lipophilic piperazine and piperidinedithiocarbamates and investigate their inhibitory potencies against cholinesterase enzymes. In the synthetic studies, 44 new compounds were isolated. The structures of the synthesized compounds were confirmed by spectroscopic analyses. Enzymatic studies were carried out using modified Ellman's assay against Acetylcholinesterase (AChE) and Butrylcholinesterase (BChE) enzymes, and it was observed that some of the compounds selectively inhibit AChE. Theoretical ADME predictions were calculated for selected compounds in the series. Enzyme kinetics and molecular docking studies were performed for the most active compound C41 and nature of inhibition and interactions between enzyme and ligand were explained. 相似文献
52.
Turkan Gencoglu Fatma Demir Duman Keziban Olcay Havva Yagci Acar Duygu Avci 《Journal of polymer science. Part A, Polymer chemistry》2018,56(24):2739-2751
The first monomers containing both phosphonate and bisphosphonate (M1) or phosphonic and bisphosphonic acid (M2) functionalities are synthesized, aiming to improve binding abilities of self-etching adhesive systems and composites: An amine having both phosphonate and bisphosphonate functionalities is prepared via Michael addition reaction between diethyl (6-aminohexyl)phosphonate and tetraethyl vinylidene bisphosphonate, its reaction with 2-isocyanatoethyl methacrylate gives M1 which is converted to M2 by selective dealkylation of the phosphonate/bisphosphonate ester groups. Their copolymerization with commercial dental monomers (bisphenol A glycidyl methacrylate, triethylene glycol dimethacrylate, and 2-hydroxyethyl methacrylate) investigated by photo-differential scanning calorimetry shows adequate photopolymerization rate and conversion. X-ray diffraction, Fourier transform infrared, and X-ray photoelectron spectroscopy analyses of M2-treated hydroxyapatite particles show formation of stable M2-calcium salts. These monomers are assessed to be not toxic according to MTT standards by in vitro cytotoxicity studies with NIH 3T3, U2OS, and Saos-2 cells. All these properties make these monomers potential candidates as biocompatible components for dental adhesives and composites. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 2739–2751 相似文献
53.
Nonlinear Dynamics - Bifurcations of periodic orbits and band zones of a one-dimensional granular array are numerically investigated in this study. A conservative two-bead system is first... 相似文献
54.
Elif Gungor Mustafa Burak Coban Hulya Kara Yasemin Acar 《Journal of Cluster Science》2018,29(6):967-974
A new cubane-based cobalt(II) cluster, [Co4L4] (1), where H2L?=?2-((E)-(2-hydroxyethylimino) methyl)-4-chlorophenol has been prepared using a solvothermal process and characterized by structural, optical and magnetism. The crystal structure of 1 consists of a tetranuclear Co4O4 core in an open-cubane framework. Each cobalt(II) ion is penta-coordinated in a distorted square pyramidal geometry (τCo1=Co1i?=?0.030, τCo2=Co2i?=?0.023). Furthermore, the photoluminescence analysis indicates that 1 has a strong blue emission which should be attributed to coordination of the metal to the ligand. The temperature dependence of the magnetic susceptibilities of 1 shows antiferromagnetic coupling (J?=???26.61?±?0.01) between cobalt(II) ions. 相似文献
55.
A systematic study on the synthesis of 8‐aminoquinoline derivatives with an n‐butyl group at each alternate position of the quinoline ring was carried out. Skraup Reaction and its Doebner–von Miller variation were used to obtain most of the quinoline ring except for the 2‐butyl‐8‐aminoquinolines and 4‐butyl‐8‐aminoquinolines where the commercially available methylquinoline derivatives were used as precursors. The structures of the synthesized compounds were characterized by FTIR, 1H‐NMR, COSY, 13C‐NMR and HRMS spectra. 相似文献
56.
The utilization of CE for monitoring bacteria–phage interaction was investigated in this study. Streptococcus thermophilus and Lactobacillus bulgaricus strains and their phages were used as model bacteria and phages for the purpose of validation in this study. CE with heterogeneous polymer polyethylene oxide was utilized for the separation of intact bacteria and investigation of phage–bacteria interaction. An intact phage detection was carried out with CZE by adding SDS in the running buffer. Calibration graphs of bacteria and phages were obtained with R2 values of 0.963 and 0.937, respectively. S. thermophilus strain was infected with its virulent phage B3‐X18 for investigation of phage–bacteria interaction. It was observed in capillary electropherogram that the culture was lysed depending on the multiplicity of infection value and it showed to be completely lysed when the multiplicity of infection value was 10. The interaction of S. thermophilus strain with L. bulgaricus phage was also investigated by using a CE and a microbiological method and it was observed that the L. bulgaricus phage attached itself to the cell wall of S. thermophilus strain without damaging the cell. 相似文献
57.
Cadmium, copper and lead in soils, sediments and spiked sea water samples have been determined by electrothermal atomic absorption spectrometry (ETAAS) with Zeeman effect background corrector using NH4NO3, Sc, Pd, Sc + NH4NO3, Pd + NH4NO3, Sc + Pd and Sc + Pd + NH4NO3 as chemical modifiers. A comprehensive comparison was made among the modifiers and without modifier in terms of pyrolysis and atomization temperatures, atomization and background absorption profiles, characteristic masses, detection limits and accuracy of the determinations. Sc + Pd + NH4NO3 modifier mixture was found to be preferable for the determination of analytes in soil and sediment certified and standard reference materials, and sea water samples because it increased the pyrolysis temperature up to 900 °C for Cd, 1350 °C for Cu and 1300 °C for Pb. Optimum masses of mixed modifier components found are 20 μg Sc + 4 μg Pd + 8 μg NH4NO3. Characteristic masses of Cd, Cu and Pb obtained are 0.6, 5.3 and 15.8 pg, respectively. The detection limits of Cd, Cu and Pb were found to be 0.08, 0.57 and 0.83 μg l−1, respectively. Depending on the solid sample type, the percent recoveries were increased up to 103% for Cd, Cu and Pb by using the proposed modifier mixture. The accuracy of the determination of analytes in the sea water samples was also increased. 相似文献
58.
Nadir Kiraz Ömer Kesmez Esin Burunkaya Leyla Budama Burçin Acar Meltem Asiltürk H. Erdem Çamurlu Ertuğrul Arpaç 《Journal of Sol-Gel Science and Technology》2010,56(3):227-235
This paper describes the preparation and characterization of glass films consisting of SiO2, Li2O, Na2O, K2O or MgO in varying compositions on stainless steel and aluminum substrates by sol–gel method. Silver phosphate or silver
incorporated zeolite was also introduced into the sols for obtaining antibacterial effect. The SiO2/Li2O/Na2O system having the composition of 85:5:10 wt% was found as the optimum for obtaining a stable sol and film formation. The
films were investigated by scanning electron microscopy (SEM) and electron dispersive analysis by X-ray (EDX), Fourier transformed
infrared (FTIR) spectroscopy, thermo-gravimetric analysis (TGA) and differential thermal analysis (DTA). Homogenous films
having 300 ± 20 nm thicknesses were formed by spin coating and then by curing at 500 °C for 1 h. Obtained films had high adherence
to the metal substrates and they were also durable in acidic, basic or NaCl environments. They also presented a powerful antibacterial
effect against E. coli. 相似文献
59.
A reaction between poly(4-vinylpyridiniumchloride) and poly(sodiumphosphate) in the presence and absence of NaCl and NaBr salts was studied in aqueous solution by conductometry. The interaction of polycation and polyanion gave insoluble polyelectrolyte complex which contained polycation and polyanion in unit mole ratio in a salt-free solution. A deviation from stoichiometry was observed at high polyion concentration and in the presence of NaCl and NaBr salts. The resultant complex showed swelling property in different solvent mixtures. A maximum degree of swelling was obtained in the solvent mixture of NaBr + water and NaBr + water + acetone. Furthermore, polyelectrolyte complex sorbed salts from aqueous electrolyte solutions. The sorption of salts increased with increasing salt concentration. © 1996 John Wiley & Sons, Inc. 相似文献
60.
Ulviye Acar Çevik Derya Osmaniye Begüm N. Sağlik Serkan Levent Betül K. Çavuşoğlu Abdullah B. Karaduman Ümide D. Özkay Yusuf Özkay Zafer A. Kaplancikli Gülhan Turan 《Journal of heterocyclic chemistry》2020,57(5):2225-2233
Monoamine oxidases (MAO) are enzymes that catalyze the oxidative deamination of monoamines such as dopamine, noradrenaline, adrenaline, and serotonin. Recent studies have shown that numerous benzothiazole derivatives exhibit hMAO inhibitory activity in the micromolar concentration range. In this study, a novel series of benzothiazole-thiadiazole (5a-5l ) was synthesized and characterized their chemical structures by 1H-NMR, 13C-NMR, and Mass spectroscopy. These compounds were evaluated as inhibitors for types A and B MAO enzymes. Compounds 5f and 5l were the most active derivatives in the series with an IC50 values of 0.107 ± 0.003 and 0.128 ± 0.004, respectively. Furthermore, cytotoxicity of compounds 5f and 5l were investigated and found as non-cytotoxic. 相似文献