New protocols for the assembly of the tetracyclic framework associated with the aromatic erythrina alkaloids

Org Lett. 2006 May 11;8(10):2143-6. doi: 10.1021/ol060642c.

Abstract

[reaction: see text] Treatment of the anion derived from the ring-fused gem-dichlorocyclopropane 4c with silver tetrafluoroborate afforded the spirocyclic compound 17 in 74% yield. Product 17 was readily converted, over three steps, into the beta-iodoethyl derivative 20 and treatment of this latter compound with n-Bu(3)SnH then afforded, in 93% yield and via a radical addition/elimination sequence, compound 2 incorporating the ABCD framework of the aromatic erythrina alkaloids.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaloids / chemical synthesis
  • Alkaloids / chemistry*
  • Alkaloids / isolation & purification*
  • Cyclization
  • Erythrina / chemistry*
  • Molecular Structure
  • Plants, Medicinal / chemistry*

Substances

  • Alkaloids