Relative configuration of natural products using NMR chemical shifts

J Nat Prod. 2009 Apr;72(4):709-13. doi: 10.1021/np8005056.

Abstract

We have measured and quantum chemically computed NMR chemical shifts for three monoterpene diastereomers produced by the walkingstick, Anisomorpha buprestoides. By taking into account the Boltzmann distribution of conformers, the combined RMSDs between experimental and calculated (1)H and (13)C NMR shifts were able to determine the correct isomer, especially when only aliphatic nuclei were used. The calculated relative energies and interproton distances were also consistent with chemical isomerization experiments and NOE-based interproton distance calculations. Complementary to the NOE-based method, a comparison between experimental and calculated NMR chemical shifts can provide an efficient method to assign the relative configuration of natural products.

Publication types

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

MeSH terms

  • Algorithms*
  • Animals
  • Biological Products / chemistry*
  • Insecta / chemistry*
  • Isomerism
  • Molecular Conformation
  • Molecular Structure
  • Monoterpenes / chemistry*
  • Nuclear Magnetic Resonance, Biomolecular / methods*

Substances

  • Biological Products
  • Monoterpenes
  • anisomorphal
  • peruphasmal
  • dolichodial