Stereostructure assignment of medium-sized rings through an NMR-computational combined approach. Application to the new germacranes ketopelenolides C and D

J Nat Prod. 2008 Dec;71(12):1988-92. doi: 10.1021/np8003547.

Abstract

The new germacrane derivatives ketopelenolides C and D have been isolated from great mugwort (Artemisia arborescens). Their stereostructure elucidation exemplifies some of the most common pitfalls facing the configurational assignment of medium-sized polyfunctionalized compounds. It was established through a combined strategy including chemical derivatization, NMR data analysis, molecular modeling, and quantum-mechanical calculations including a comparison between experimental 13C NMR data and a Boltzmann-weighted average of DFT-calculated 13C NMR chemical shifts.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Artemisia / chemistry*
  • Computer Simulation
  • Molecular Conformation
  • Molecular Structure
  • Nuclear Magnetic Resonance, Biomolecular
  • Sesquiterpenes, Germacrane / chemistry*
  • Sesquiterpenes, Germacrane / isolation & purification*
  • Stereoisomerism

Substances

  • Sesquiterpenes, Germacrane
  • ketopelenolide C
  • ketopelenolide D