Total synthesis of hyacinthacines B₃, B₄, and B₅ and purported hyacinthacine B₇, 7-epi-hyacinthacine B₇, and 7a-epi-hyacinthacine B₃ from a common precursor

J Org Chem. 2014 May 16;79(10):4569-81. doi: 10.1021/jo5005923. Epub 2014 May 5.

Abstract

The total synthesis of hyacinthacines B3, B4, and B5 and purported hyacinthacine B7, 7-epi-hyacinthacine B7, and 7a-epi-hyacinthacine B3 from a common anti-1,2-amino alcohol precursor is described. These syntheses confirmed that the proposed structures and absolute configurations of hyacinthacines B3, B4, and B5 were correct and disclosed that the proposed structure of hyacinthacine B7 was incorrect. Our synthetic and spectroscopic studies suggest that the natural hyacinthacines B5 and B7 are the same compounds; however, without access to authentic samples this cannot be unequivocally proven.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Pyrrolizidine Alkaloids / chemical synthesis*
  • Pyrrolizidine Alkaloids / chemistry
  • Stereoisomerism

Substances

  • Pyrrolizidine Alkaloids
  • hyacinthacine B3
  • hyacinthacine B4
  • hyacinthacine B5
  • hyacinthacine B7