Practical synthesis of lespedezol A1

J Nat Prod. 2008 Feb;71(2):275-7. doi: 10.1021/np070493m. Epub 2008 Jan 31.

Abstract

A practical formal synthesis of lespedezol A 1 ( 1) was accomplished in 33% yield for four steps starting from formation of the substituted chalcone. Of particular note is a useful protocol for reduction of the 2-ene bond in the isoflavone intermediate. A significant improvement in the final ring closure when water was scavenged from the reaction is also noteworthy. The ready availability of lespedezol A 1 will provide material for further pharmacological evaluation and for exploration of the pterocarpene nucleus as a potential entry into various 6a-hydroxypterocarpans.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Benzopyrans / chemical synthesis*
  • Benzopyrans / chemistry
  • Chalcones / chemistry*
  • Heterocyclic Compounds, 4 or More Rings / chemical synthesis*
  • Heterocyclic Compounds, 4 or More Rings / chemistry
  • Lespedeza / chemistry
  • Molecular Structure
  • Plants, Medicinal / chemistry

Substances

  • 6a-hydroxypterocarpan
  • Benzopyrans
  • Chalcones
  • Heterocyclic Compounds, 4 or More Rings
  • lespedezol A1