Synthetic Study of Dragmacidin E: Enantioselective Construction of the Seven-Membered Ring-Fused Indole Skeleton with Contiguous Stereocenters

J Org Chem. 2023 Jun 16;88(12):7674-7683. doi: 10.1021/acs.joc.2c02216. Epub 2023 Jan 26.

Abstract

We developed an enantioselective synthetic method of constructing a seven-membered ring-fused indole skeleton with contiguous stereocenters for the synthesis of dragmacidin E. Introduction of chirality at the benzylic position was achieved by Ir-catalyzed asymmetric hydrogenation. After construction of the tricyclic molecular framework using Pd-catalyzed cascade cyclization, the tetrasubstituted carbon center was created using the Ag nitrene-mediated C-H amination reaction. The developed method provided access to the functionalized seven-membered ring-fused indole skeleton with a hydroxymethyl branch in the tetrasubstituted carbon.

MeSH terms

  • Carbon*
  • Catalysis
  • Indole Alkaloids*
  • Skeleton
  • Stereoisomerism

Substances

  • dragmacidin E
  • Indole Alkaloids
  • Carbon