Anionic polycyclization entry to tricycles related to quassinoids and terpenoids: a stereocontrolled total synthesis of (+)-cassaine

J Org Chem. 2014 Sep 5;79(17):7979-99. doi: 10.1021/jo501122k. Epub 2014 Aug 7.

Abstract

A full account of our anionic polycyclization approach to access highly functionalized tricycles related to quassinoids and terpenoids from several optically active bicyclic enone systems and Nazarov reagents is presented. (+)-Carvone is the only chiral source used to fix the entire stereochemistry of all of the tricycles, and the stereochemical outcome of this process was unambiguously determined by X-ray crystallographic analysis. The utility of this strategy was demonstrated by the stereocontrolled construction of advanced tricycles related to the highly potent anticancer natural product bruceantin, a member of quassinoid family, and the total synthesis of the cardioactive terpenoid (+)-cassaine, a nonsteroidal inhibitor of Na(+)-K(+)-ATPase.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abietanes
  • Alkaloids / chemical synthesis*
  • Alkaloids / chemistry*
  • Anions / chemistry*
  • Biological Products
  • Crystallography, X-Ray
  • Cyclization
  • Cyclohexane Monoterpenes
  • Humans
  • Monoterpenes / chemistry*
  • Quassins / chemistry*
  • Quassins / pharmacology
  • Sodium-Potassium-Exchanging ATPase / antagonists & inhibitors
  • Sodium-Potassium-Exchanging ATPase / chemistry
  • Stereoisomerism
  • Terpenes / chemistry*

Substances

  • Abietanes
  • Alkaloids
  • Anions
  • Biological Products
  • Cyclohexane Monoterpenes
  • Monoterpenes
  • Quassins
  • Terpenes
  • carvone
  • Sodium-Potassium-Exchanging ATPase
  • cassaine
  • bruceantin