C-24 stereochemistry of marine sterols: (22E)-24-(isopropenyl)-22-dehydrocholesterol and 24-isopropenylcholesterol

Chem Pharm Bull (Tokyo). 2006 Oct;54(10):1473-7. doi: 10.1248/cpb.54.1473.

Abstract

The C-24 configuration of (22E,24xi)-24-isopropenyl-22-dehydrocholesterol (1), which was recently isolated from the Colombian Caribbean sponge, Topsentia ophiraphidites, was investigated. Synthesis of the stereodefined (24R)- and (24S)-(22E)-24-isopropenyl-22-dehydrocholesterols (1a, 1b) followed by (1)H- and (13)C-NMR data comparison of these sterols established the (24R)-configuration of 1. In addition, (24R)- and (24S)-24-isopropenylcholesterols (2a and 2b) were also synthesized and their NMR data are provided. The C-24 configurations of the samples of 24-isopropenylcholesterol reported previously are discussed.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dehydrocholesterols* / chemistry
  • Dehydrocholesterols* / isolation & purification
  • Magnetic Resonance Spectroscopy / methods
  • Magnetic Resonance Spectroscopy / standards
  • Molecular Conformation
  • Porifera / chemistry*
  • Reference Standards
  • Sensitivity and Specificity
  • Species Specificity
  • Stereoisomerism
  • Sterols / chemistry*
  • Sterols / isolation & purification

Substances

  • 24-isopropenyl-22-dehydrocholesterol
  • Dehydrocholesterols
  • Sterols