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171.
172.
Herein, novel silver-based N-heterocyclic carbene (NHC) complexes bearing 2-(4-hydroxyphenyl)ethyl group were synthesized. Novel Ag(I)NHC complexes were synthesized from the 2-(4-hydroxyphenyl)ethyl-substituted benzimidazolium salts and silver oxide via in situ deprotonation method. The successful formation of all Ag(I)NHC complexes was proved by using 1H NMR, 13C NMR, FTIR spectroscopy, and elemental analysis techniques. In addition, their inhibitory effects have been investigated of these substances on acetylcholinesterase (AChE), α-glycosidase (α-Gly), human carbonic anhydrase I (hCA I), and human carbonic anhydrase II (hCA II) enzymes. It has been seen that all compounds have a better ability to inhibit compared with existing tried inhibitors. Among these, the best inhibitor against AChE enzyme is 1g (Ki : 9.54 ± 0.98 μM and IC50 : 17.40), and against α-Gly, 1c showed the highest effect (Ki 3.09 ± 0.36 μM and IC50 7.91). The best inhibitor against hCA I and hCA II enzymes are 1c and 1g compounds. For hCA I and hCA II, IC50 values were calculated as 17.85 and 9.06 μM and Ki values were measured as 5.45 ± 2.02 and 8.99 ± 2.02 μM, respectively.  相似文献   
173.
High Energy Chemistry - The quenching of fluorescence (FL) of uranyl ion $${\text{UO}}_{2}^{{2 + }}$$ and tryptophan Trp during their selective intracomplex photoexcitation in aqueous and methanol...  相似文献   
174.
Chemistry of Natural Compounds - The photophysical and photochemical processes of N-deacetyllappaconitine (DAL) and its hydrobromide (DAL·HBr) in aqueous solutions were investigated. Their...  相似文献   
175.
Mu  D. D.  Zhao  Y. X.  Sun  G. Y.  Bobakulov  Kh. M.  Aisa  H. A.  Wu  T. 《Chemistry of Natural Compounds》2021,57(5):939-941
Chemistry of Natural Compounds -  相似文献   
176.
Gas-phase electrophoresis yields size distributions of polydisperse, aerosolized analytes based on electrophoretic principles. Nanometer-sized, surface-dry, single-charged particles are separated in a high laminar sheath flow of particle-free air and an orthogonal tunable electric field. Additionally, nano Electrospray Gas-Phase Electrophoretic Mobility Molecular Analyzer (nES GEMMA) data are particle-number based. Therefore, small particles can be detected next to larger ones without a bias, for example, native proteins next to their aggregates. Analyte transition from the liquid to the gas phase is a method inherent prerequisite. In this context, nonvolatile sample buffers influence results. In the worst case, the (bio-)nanoparticle signal is lost due to an increased baseline and unspecific clustering of nonvolatile components. We present a novel online hyphenation of liquid chromatography and gas-phase electrophoresis, coupling a size-exclusion chromatography (SEC) column to an advanced nES GEMMA. Via this novel approach, it is possible to (i) separate analyte multimers already present in liquid phase from aggregates formed during the nES process, (ii) differentiate liquid phase and spray-induced multimers, and (iii) to remove nonvolatile buffer components online before SEC–nES GEMMA analysis. Due to these findings, SEC–nES GEMMA has the high potential to help to understand aggregation processes in biological buffers adding the benefit of actual size determination for noncovalent assemblies formed in solution. As detection and characterization of protein aggregation in large-scale pharmaceutical production or sizing of noncovalently bound proteins are findings directly related to technologically and biologically relevant situations, we proposed the presented method to be a valuable addition to LC-MS approaches.  相似文献   
177.
Kinetics and Catalysis - The catalytic performance of a bimetallic RhIn/SiO2 catalyst was studied in the liquid-phase hydrogenation of nitrobenzene. The formation of intermetallic Rh1In1...  相似文献   
178.
JETP Letters - The structural and magnetic properties of the Co7Te8 layered compound have been studied for the first time using X-ray diffraction, measurements of the magnetic susceptibility, and...  相似文献   
179.
Kinetics and Catalysis - Cyclic biscarbonates were synthesized from CO2 and diepoxides in the presence of a chromium(III) salen complex. The effect of the reaction conditions on the process...  相似文献   
180.
Moscow University Chemistry Bulletin - A piezoactive nanofiber composite PVDF film with TiO2 nanoparticles included in it was synthesized by electrospinning. The composition, morphology and...  相似文献   
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