Enantioselective Total Synthesis of Dysiherbols A, C, and D

J Am Chem Soc. 2022 Oct 26;144(42):19521-19531. doi: 10.1021/jacs.2c08435. Epub 2022 Oct 13.

Abstract

Herein, we report the enantioselective total synthesis of dysiherbols A, C, and D, a unique group of 6/6/5/6/6 pentacyclic quinone/hydroquinone sesquiterpenes, featuring a photo-induced quinone-alkene [2 + 2] cycloaddition and a tandem [1,2]-anionic rearrangement/cyclopropane fragmentation as key elements. Based on our total synthesis, the originally proposed structures of dysiherbols C and D have been revised. Detailed computational studies were carried out to gain deep insight into the unprecedented [1,2]-anionic rearrangement, which revealed that the transformation, albeit a symmetry-forbidden process, proceeded through a concerted manner owing to the release of high ring-strain energy and the evolution of local aromaticity in the transition state. Taking all, the present work offers a mechanistically interesting and synthetically useful approach to accessing dysiherbols and related congeners.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkenes
  • Cyclopropanes
  • Hydroquinones*
  • Quinones
  • Sesquiterpenes* / chemistry
  • Stereoisomerism

Substances

  • Hydroquinones
  • Sesquiterpenes
  • Quinones
  • Alkenes
  • Cyclopropanes