Antimycobacterial triterpenes from Melia volkensii

J Nat Prod. 1999 Apr;62(4):546-8. doi: 10.1021/np980288u.

Abstract

In a bioassay-guided search for antimycobacterial compounds from higher plants, we have chemically investigated methanolic extracts of seeds of Melia volkensii. Chromatographic fractions provided two new euphane (20R)-type triterpenoids. The structures of the new compounds, 12beta-hydroxykulactone (1) and 6beta-hydroxykulactone (2), were elucidated by 1D and 2D NMR (13C, 1H, 1H-1H COSY, HMQC, HMBC, and NOESY spectra) and FABMS studies and shown to be hydroxyl derivatives of kulactone (3). Also isolated was the known kulonate (4). In a radiorespirometric bioassay against Mycobacterium tuberculosis, compounds 1, 2, and 4 exhibited minimum inhibitory concentrations of 16, 4, and 16 microg/mL, respectively.

Publication types

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

MeSH terms

  • Antitubercular Agents / isolation & purification
  • Antitubercular Agents / pharmacology*
  • Chromatography, High Pressure Liquid
  • Kenya
  • Lactones / isolation & purification
  • Lactones / pharmacology*
  • Magnetic Resonance Spectroscopy
  • Mass Spectrometry
  • Methanol
  • Mycobacterium tuberculosis / drug effects*
  • Mycobacterium tuberculosis / metabolism
  • Oxygen / metabolism
  • Plants, Medicinal / chemistry*
  • Seeds / chemistry
  • Spectrophotometry, Ultraviolet

Substances

  • Antitubercular Agents
  • Lactones
  • hydroxykulactone
  • Oxygen
  • Methanol