We report herein a protocol for an organocatalyzed asymmetric vinylogous Michaeladdition of aryl alkane nucleophiles with enals under base- and additive-free conditions. A series of allylic building blocks were obtained in 60%–93% yield and 88–99% ee with 20 mol % diphenylprolinol silyl ether as catalyst. This protocol has advantages such as excellent chemoselectivity and regioselectivity, good tolerance
我们在此报告了在无碱和无添加剂的条件下,芳基烷烃亲核试剂与烯醇发生有机催化的不对称插烯迈克尔加成的方案。以 20 mol% 二苯基脯氨醇甲硅烷基醚为催化剂,以 60%–93% 的收率和 88–99% ee 获得了一系列烯丙基结构单元。该方案具有优异的化学选择性和区域选择性、功能耐受性好、反应条件简单等优点。
Permeant fluorescent probes visualize the activation of SARM1 and uncover an anti-neurodegenerative drug candidate
作者:Wan Hua Li、Ke Huang、Yang Cai、Qian Wen Wang、Wen Jie Zhu、Yun Nan Hou、Sujing Wang、Sheng Cao、Zhi Ying Zhao、Xu Jie Xie、Yang Du、Chi-Sing Lee、Hon Cheung Lee、Hongmin Zhang、Yong Juan Zhao
DOI:10.7554/elife.67381
日期:——
screening identified a derivative of nisoldipine as a covalent inhibitor of SARM1 that reacted with the cysteines, especially Cys311 in its ARM domain and blocked its NMN-activation, protecting axons from degeneration. The Cryo-EM structure showed that SARM1 was locked into an inactive conformation by the inhibitor, uncovering a potential neuroprotective mechanism of dihydropyridines.
Enantioselective 1,3-Dipolar (5+3) Cycloadditions of Oxidopyrylium Ylides and Vinylcyclopropanes toward 9-Oxabicyclononanes
作者:Yanfeng Gao、Yuanhao Mao、Zhiwei Miao
DOI:10.1021/acs.orglett.2c01037
日期:2022.4.29
We have developed an efficient and mild enantioselective palladium-catalyzed (5+3) cycloaddition of vinylcyclopropanes and oxidopyryliumylides generated in situ from benzopyranones, in the presence of a chiral PHOX ligand. These reactions afford various highly functionalized bridged oxa-[3.3.1]carbocycles with three stereogenic centers that are challenging to synthesize, in moderate to good yields