Six-Step Total Synthesis of (±)-Conolidine

J Nat Prod. 2019 Nov 22;82(11):2972-2978. doi: 10.1021/acs.jnatprod.9b00302. Epub 2019 Nov 5.

Abstract

A concise total synthesis of (±)-conolidine, a potent nonopioid analgesic, in 19% overall yield is described here. A gold(I)-catalyzed Conia-ene reaction (Toste cyclization) and a Pictet-Spengler reaction served as key transformations for assembling the 1-azabicyclo[4.2.2]decane core and defining the geometry of the exocyclic double bond. The activation energies of formation of the vinyl-gold intermediates were calculated and revealed a silyl enol ether with an unprotected indole moiety as a suitable precursor for the Toste cyclization. This six-step synthesis did not involve any nonstrategic redox manipulations.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Analgesics, Non-Narcotic / chemical synthesis*
  • Analgesics, Non-Narcotic / pharmacology
  • Bridged Bicyclo Compounds
  • Catalysis
  • Cyclization
  • Indole Alkaloids / chemical synthesis*
  • Indole Alkaloids / pharmacology
  • Indoles
  • Molecular Structure
  • Stereoisomerism

Substances

  • Analgesics, Non-Narcotic
  • Bridged Bicyclo Compounds
  • Indole Alkaloids
  • Indoles
  • conolidine