A green route for the synthesis of 2-substituted benzoxazole derivatives catalyzed by Al3+-exchanged K10 clay
摘要:
A new, simple, and efficient protocol is developed for the synthesis of 2-substituted benzoxazole derivatives through N-C-O bond formation using Al3+-exchanged K10 clay (Al3+-K10) as catalyst. A wide range of benzoxazole derivatives are synthesized in high yields without affecting many functional groups. Hot filtration experiments showed the absence of metal leaching and catalyst can be reused for five times with only a slight decrease in yield. (C) 2013 Elsevier Ltd. All rights reserved.
Tertiary Amine-Catalyzed Acyl Group Exchange Reaction of<i>N</i>,<i>O</i>-Diacyl-<i>o</i>-aminophenols. Its Mechanism and Factors Determining the Relative Stability of Acyl Exchanged Isomer Pairs
polarities. It was found that the relativestability of acyl exchanged isomer pairs is determined solely by the inductive effect of acyl groups, provided that the steric hindrance of acyl substituents bonded to amide nitrogen affects the stability to the same extent. The importance of steric hindrance exerted by a bulky acyl group in determining the relativestability was demonstrated by analyzing the
A Rearrangement of 4-Phenylbenzo[d]oxazoles to Phenanthridin-4-ols
作者:Alexander S. Fisyuk、Anton L. Shatsauskas、Ekaterina S. Keyn、Anton J. Stasyuk、Sergey A. Kirnosov、Vladislav Yu. Shuvalov、Anastasia S. Kostyuchenko
DOI:10.1055/a-2193-5593
日期:2024.2
A new approach was developed for the synthesis of phenanthridin-4-ols and 4-hydroxyphenanthridin-6(5H)-one derivatives in 43–89% yields based on the AlCl3-mediated rearrangement of available 4-phenylbenzo[d]oxazoles and 4-phenyl-1,3-benzoxazol-2(3H)-one. The quantum chemical calculations were used to describe the mechanism and predict the thermodynamic parameters of the reaction under study.
Supported Pd-catalyzed ring opening and chemoselective aminocarbonylative coupling of benzoxazoles with aryl iodides
作者:Pushkar Mehara、Ajay Kumar Sharma、Ashish Kumar、Poonam Sharma、Pralay Das
DOI:10.1039/d4cy00070f
日期:——
A tandem approach using polystyrene supported Pd catalyzed ring opening aminocarbonylative coupling of benzoxazoles with aryl iodides has been developed for the synthesis of N-(2-hydroxyphenyl)benzamides using solid oxalic acid as the CO source.
以固体草酸为 CO 源,开发了一种串联方法,利用聚苯乙烯支撑的钯催化苯并恶唑与芳基碘化物的开环氨基羰基偶联合成 N-(2-羟基苯基)苯甲酰胺。
Biochemical and Structural Evaluation of Highly Selective 2-Arylbenzoxazole-Based Transthyretin Amyloidogenesis Inhibitors
作者:Steven M. Johnson、Stephen Connelly、Ian A. Wilson、Jeffery W. Kelly
DOI:10.1021/jm0708735
日期:2008.1.1
To develop potent transthyretin (TTR) amyloidogenesis inhibitors that also display high binding selectivity in blood, it proves useful to systematically optimize each of the three substructural elements that comprise a typical inhibitor: the two aryl rings and the linker joining them. In the first study, described herein, structural modifications to one aryl ring were evaluated by screening a library of 2-arylbenzoxazoles bearing thyroid hormone-like aryl substituents on the 2-aryl ring. Several potent and highly selective amyloidogenesis inhibitors were identified that exhibit minimal thyroid hormone nuclear receptor and COX-1 binding. High resolution crystal structures (1.3-1.5 angstrom) of three inhibitors (2f, 4f, and 4d) in complex with TTR were obtained to characterize their binding orientation. Collectively, the results demonstrate that thyroid hormone-like substitution patterns on one aryl ring lead to potent and highly selective TTR amyloidogenesis inhibitors that lack undesirable thyroid hormone receptor or COX-1 binding.