Cytotoxic steroidal alkaloids from Kibatalia laurifolia

J Nat Prod. 2011 May 27;74(5):1236-40. doi: 10.1021/np200165t. Epub 2011 Mar 28.

Abstract

Four new steroids, 3-epi-gitingensine (1), N-acetylgitingensine (6), kibalaurifoline (7) and kibalaurifenone (8), along with the known paravallarine (2), 7α-hydroxyparavallarine (3), gitingensine (4), and N-methylgitingensine (5) were isolated from the leaves of Kibatalia laurifolia. Their structures were determined primarily from mass spectrometry and 2D NMR analyses. On the basis of the known absolute configurations of 2 and 4, the absolute configurations of the new compounds were proposed. Due to the structural relationships of compounds 1-8, a biosynthetic pathway was suggested. Compound 2 was cytotoxic to KB cells (IC50 12.8 μM), followed by 1 with IC50 21.2 μM.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaloids / chemistry
  • Alkaloids / isolation & purification*
  • Alkaloids / pharmacology*
  • Antineoplastic Agents, Phytogenic / chemistry
  • Antineoplastic Agents, Phytogenic / isolation & purification*
  • Antineoplastic Agents, Phytogenic / pharmacology*
  • Apocynaceae / chemistry*
  • Drug Screening Assays, Antitumor
  • Humans
  • KB Cells
  • Nuclear Magnetic Resonance, Biomolecular
  • Plant Leaves / chemistry
  • Steroids / chemistry
  • Steroids / isolation & purification*
  • Steroids / pharmacology*
  • Vietnam

Substances

  • Alkaloids
  • Antineoplastic Agents, Phytogenic
  • Steroids