Triterpenoidal alkaloids from Buxus natalensis and their acetylcholinesterase inhibitory activity

J Nat Prod. 2010 Nov 29;73(11):1858-62. doi: 10.1021/np100494u. Epub 2010 Oct 18.

Abstract

Acetylcholinesterase (AChE) inhibition-directed phytochemical studies on the methanolic extract of Buxus natalensis, collected in South Africa, resulted in the isolation of 12 compounds: O(2)-natafuranamine (1), O(10)-natafuranamine (2), cyclonataminol (3), 31-demethylbuxaminol A (4), buxaminol A (5), buxafuranamide (6), buxalongifolamidine (7), buxamine A (8), cyclobuxophylline K (9), buxaminol C (10), methyl syringate (11), and p-coumaroylputrescine (12). Compounds 1-4 were new alkaloids, and compound 5 was isolated for the first time as a natural product. Their structures were elucidated with the aid of extensive NMR and mass spectroscopic studies. Compounds 1 and 2 are members of a rarely occurring class of Buxus alkaloids, having a tetrahydrofuran ring incorporated in their structures. Compounds 1-12 exhibited strong to moderate AChE inhibitory activity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkaloids / chemistry
  • Alkaloids / isolation & purification*
  • Alkaloids / pharmacology*
  • Buxus / chemistry*
  • Cholinesterase Inhibitors / chemistry
  • Cholinesterase Inhibitors / isolation & purification*
  • Cholinesterase Inhibitors / pharmacology*
  • Dose-Response Relationship, Drug
  • Molecular Structure
  • Nuclear Magnetic Resonance, Biomolecular
  • Plants, Medicinal / chemistry*
  • South Africa
  • Triterpenes / chemistry
  • Triterpenes / isolation & purification*
  • Triterpenes / pharmacology*

Substances

  • Alkaloids
  • Cholinesterase Inhibitors
  • Triterpenes