Total Synthesis of (-)-Gardmultimine A

Org Lett. 2020 Mar 6;22(5):2022-2025. doi: 10.1021/acs.orglett.0c00399. Epub 2020 Feb 25.

Abstract

The first total synthesis of Gardneria oxindole alkaloid (-)-gardmultimine A has been achieved in 19 steps from d-tryptophan in a fully stereocontrolled manner. This synthesis features (1) an Ir-catalyzed regioselective C-H borylation/oxidation sequence to introduce the C12 methoxyl group, (2) a stereocontrolled oxidative rearrangement of indole to construct the spirooxindole motif, and (3) an Au(I)-catalyzed transannular Conia-ene-type 6-exo-dig cyclization to establish the azabicyclo[2.2.2]octane skeleton and the exocyclic E-alkene with exclusive stereoselectivity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Catalysis
  • Cyclization
  • Molecular Structure
  • Oxidation-Reduction
  • Tryptophan / chemistry*

Substances

  • Tryptophan