Asymmetric Total Synthesis and Biological Evaluation of the Natural PDE4 Inhibitor Toddacoumalone
作者:Ke-Qiang Hou、Xue-Ping Chen、Yiyou Huang、Albert S. C. Chan、Hai-Bin Luo、Xiao-Feng Xiong
DOI:10.1021/acs.orglett.9b04355
日期:2020.1.17
We describe herein the first asymmetric totalsynthesis and biologicalevaluation of the natural PDE4 inhibitor toddacoumalone and its stereoisomers. The key step of the totalsynthesis is a formal asymmetric [4 + 2] cycloaddition reaction catalyzed by chiral secondary amine catalysts. A variety of pyranoquinolinones and 3-methylcrotonaldehyde are well tolerated under the optimized reaction conditions
Asymmetric synthesis of tetrahydropyran[3,2-c]quinolinones via an organocatalyzed formal [3 + 3] annulation of quinolinones and MBH 2-naphthoates of nitroolefin
An efficient asymmetric and enantio-swithchable organocatalytic [3 + 3] annulation reaction using MBH-2-naphthoates of nitroalkenes and 4-hydroxyquinolin-2(1H)-ones has been developed. Densely substituted tetrahydropyrano[3,2-c]quinolinones scaffolds with two adjacent stereogenic centers are obtained with high yield (up to 95% yield) and good stereoselectivities (up to >20:1 dr and 96% ee) in an enantio-switchable manner. Furthermore, gram scale synthesis was achieved and the nitro group could easily transform into an amino group without any appreciable loss in the diastereo- and enantioselectivity. (C) 2019 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.
ANTIVIRAL COMPOUNDS AND ANTIHYPERTENSIVE COMPOUNDS