np990336q_si_001.pdf (255.93 kB)
Thirteen Novel Cycloartane-Type Triterpenes from Combretum quadrangulare
journal contribution
posted on 1999-11-24, 00:00 authored by Arjun H. Banskota, Yasuhiro Tezuka, Kim Qui Tran, Ken Tanaka, Ikuo Saiki, Shigetoshi KadotaThirteen novel cycloartane-type triterpenes were isolated from Combretum quadrangulare, a Vietnamese
medicinal plant. The structures of the novel triterpenes were determined by spectroscopic methods as
well as by chemical transformations. Among those compounds, quadrangularic acids F (1), G (2), and H
(4) and 24-epiquadrangularic acid G (3) are the first examples of cycloartane-type triterpenes bearing
carboxylic acid groups at both C-4 and C-20. Furthermore, norquadrangularic acid A (13) is the first
example of a trinorcycloartane-type triterpene isolated from the genus Combretum.