Stereoselective Total Syntheses of C18-Oxo Eburnamine-Vincamine Alkaloids

Org Lett. 2022 Apr 1;24(12):2409-2413. doi: 10.1021/acs.orglett.2c00661. Epub 2022 Mar 21.

Abstract

Here, we disclose the divergent total syntheses of representative C18-oxo eburnamine-vincamine alkaloids (+)-eburnaminol, (-)-larutenine, and (-)-cuanzine. Key to the approach is a substrate-controlled iridium-catalyzed asymmetric hydrogenation/lactamization cascade that leads to the formation of the common tetracyclic skeleton with essential cis-C20/C21 stereochemistry (93% yield, 98% ee, >20:1 dr, gram scale). Access to the targeted alkaloids is effected late in the synthesis by implementation of a number of diversity-oriented transformations and late-stage modifications.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaloids*
  • Iridium
  • Stereoisomerism
  • Vincamine*

Substances

  • Alkaloids
  • Iridium
  • Vincamine