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11.
Haichao Zhu Meihua Liu Haiyan Li Ting Guan Qi Zhang Yang Chen Yingxiang Liu Rolf R. Hartmann Lina Yin Qingzhong Hu 《中国化学快报》2021,32(7):2327-2332
Exorbitant aldosterone is closely associated with various severe diseases, including congestive heart failure and chronic kidney disease. As aldosterone synthase is the pivotal enzyme in aldosterone biosynthesis, its inhibition constitutes a promising treatment for these diseases. Via a structure-based approach, a series of pyridyl substituted 3,4-dihydrobenzo[f][1,4]oxazepin-5(2H)-ones were designed as inhibitors of aldosterone synthase. Six compounds (5j, 5l, 5m 5w, 5x and 5y) distinguished themselves with potent inhibition (IC50 <100 nmol/L) and high selectivity over homogenous 11β-hydroxylase. As the most promising compound, 5x exhibited an IC50 of 12 nmol/L and an excellent selectivity factor (SF) of 157, which are both superior to those of the reference fadrazole (IC50 = 21 nmol/L, SF = 7). Importantly, 5x showed no inhibition against steroidogenic CYP17, CYP19 and a panel of hepatic CYP enzymes indicating an outstanding safety profile. As it manifested satisfactory pharmacokinetic properties in rats, compound 5x was considered as a drug candidate for further development. 相似文献
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13.
《Analytical letters》2012,45(9):775-783
Abstract A modification of a fluorescence assay method for β-cyanoalanine synthase has been described which involves the direct coupling of the product of cyanide and cysteine to resazurin, to produce the fluorescent resosurfin, The fluorescence produced was found to be directly proportional to the rate of the reaction. 相似文献
14.
A QM/MM study on the reaction pathway leading to 2‐Aceto‐2‐hydroxybutyrate in the catalytic cycle of AHAS 下载免费PDF全文
Leslie Sánchez Gonzalo A. Jaña Eduardo J. Delgado 《Journal of computational chemistry》2014,35(6):488-494
The reaction between the intermediate 2‐hydroxyethyl‐thiamin diphosphate (HEThDP?) and 2‐ketobutyrate, in the third step of the catalytic cycle of acetodydroxy acid synthase, is addressed from a theoretical point of view by means of hybrid quantum/molecular mechanical calculations. The QM region includes one molecule of 2‐ketobutyrate, the HEThDP? intermediate, and the residues Arg 380 y Glu 139; whereas the MM region includes the rest of the protein. The study includes potential energy surface scans to identify and characterize critical points on it, transition state search and activation barrier calculations. The results show that the reaction occurs via a two‐step mechanism corresponding to the carboligation and proton transfer in the first stage; and the product release in the second step. © 2014 Wiley Periodicals, Inc. 相似文献
15.
Mohaimed I. Al-Hassan 《合成通讯》2013,43(3):353-356
It was found that diphenylacetylene reacts at 55[ddot]C with i-Bu2AlH to form cis-vinylalane. On the other hand, i-Bu2AlH adds mostly in anti-manner to diphenylacetylene at 110[ddot] C. 相似文献
16.
In this study, first, a series of chalcone compounds S1–S6 were synthesized from various acetophenone derivatives (acetophenone, p-methyl acetophenone, and p-methoxy acetophenone) and aromatic aldehyde derivatives (benzaldehyde, p-methyl benzaldehyde, and p-methoxy benzaldehyde) by the Claisen–Schmidt condensation reaction. These S1–S6 compounds were then used in the preparation of 4,5-dihydropyrazol-1-yl derivatives S7–S15. Finally, four new compounds S16–S19 were synthesized from compound (S7, S8, S9, and S12) and 2,4-dinitrophenylhydrazine. Therefore, three known and ten new heterocyclic compounds were synthesized and completely characterized using 1H NMR, 13C NMR, IR, and elemental analysis. 相似文献
17.
3-Phenyl-1-(thiophen-2-yl)prop-2-en-1-one obtained by Claisen–Schmidt condensation of 2-acetyl thiophene with benzaldehyde was converted into 2,3-dibromo-3-phenyl-1-(thiophen-2-yl)propan-1-one, which on treatment with various thiosemicarbazides in the presence of triethylamine in absolute ethanol, yielded the corresponding hydroxy pyrazolines 3a–h. All the compounds were characterized by IR, 1H NMR, and 13C NMR spectra. 相似文献
18.
The article describes an efficient, economical, and environmentally friendly approach for Michael addition of diethyl malonate to ferrocenyl substituted chalcones in the presence of microwave irradiation under solvent-free conditions, affording the corresponding Michael adducts in moderate to good yields of 53–94%.
19.
《合成通讯》2013,43(14):1903-1909
Abstract This article describes a fast, efficient, economical, and environmentally friendly method for the preparation of a series of ferrocenyl‐substituted 1,5‐diketone compounds via Michael addition of ferrocenyl‐substituted chalcones with deoxybenzoin or dibenzyl ketone under solvent‐free conditions, and affords the corresponding Michael adducts with excellent yields of 77–93%. 相似文献
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