21beta-Hydroxy-oleanane-type triterpenes from Hippocratea excelsa

Phytochemistry. 2008 Feb;69(4):1057-64. doi: 10.1016/j.phytochem.2007.10.016. Epub 2007 Dec 3.

Abstract

Stem bark of Hippocratea excelsa afforded six pentacyclic triterpenes, five oleanane and one ursane types. They were identified as 11beta,21beta-dihydroxy-olean-12-ene-3-one (2), 3alpha,11alpha,21beta-trihydroxy-olean-12-ene (3), 3alpha,21beta-dihydroxy-11alpha-methoxy-olean-12-ene (4), 3alpha,21beta-dihydroxy-olean-9(11),12-diene (5), 3alpha,21beta-dihydroxy-olean-12-ene (6) and 3alpha,21beta-dihydroxy-11alpha-methoxy-urs-12-ene, isolated as its diacetate derivative (7), as well as 3alpha,21beta-dihydroxy-olean-12-ene (1) previously isolated from the root bark. The known alpha- and beta-amyrin, oleanoic and ursolic acids, trans-polyisoprene, and the ubiquitous beta-sitosterol were also isolated. Structures were elucidated on the basis of spectroscopic analyses, including homo- and heteronuclear correlation NMR experiments (COSY, ROESY, HSQC and HMBC) and comparison with literature data. The antigiardial activity of compounds 2-5 was not significant.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Hippocrateaceae / chemistry*
  • Magnetic Resonance Spectroscopy
  • Molecular Structure
  • Oleanolic Acid / analogs & derivatives
  • Oleanolic Acid / chemistry*
  • Oleanolic Acid / isolation & purification
  • Pentacyclic Triterpenes / chemistry
  • Pentacyclic Triterpenes / isolation & purification
  • Plant Bark / chemistry
  • Triterpenes / chemistry
  • Triterpenes / isolation & purification
  • Ursolic Acid

Substances

  • Pentacyclic Triterpenes
  • Triterpenes
  • Oleanolic Acid
  • beta-amyrin