Enantioselective total synthesis of tricyclic myrmicarin alkaloids

Org Lett. 2005 Sep 29;7(20):4423-6. doi: 10.1021/ol051629f.

Abstract

[reaction: see text] An enantioselective gram-scale synthesis of a key dihydroindolizine intermediate for the preparation of myrmicarin alkaloids is described. Key transformations in this convergent approach include a stereospecific palladium-catalyzed N-vinylation of a pyrrole with a vinyl triflate, a copper-catalyzed enantioselective conjugate reduction of a beta-pyrrolyl enoate, and a regioselective Friedel-Crafts reaction. The synthesis of optically active and isomerically pure samples of (4aR)-myrmicarins 215A, 215B, and 217 in addition to their respective C4a-epimers is presented.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaloids / chemical synthesis*
  • Alkaloids / chemistry*
  • Cyclization
  • Heterocyclic Compounds, 3-Ring / chemistry*
  • Molecular Structure
  • Stereoisomerism

Substances

  • Alkaloids
  • Heterocyclic Compounds, 3-Ring
  • myrmicarin