Chemical constituents of Cordia piauhiensis -: Boraginaceae

A new monodesmoside triterpenoid saponin characterized as 3 beta-O-alpha-L-rhamnopyranosyl-(1 -> 2)-beta-D-glucopyranosyl pomolic acid, was isolated from Cordia piauhiensis Fresen ( Boraginaceae). Its structure was determined by extensive NMR analysis, including H-1, H-1-COSY, HMQC, HMBC, and NOESY experiments. In addition, four known triterpenoids: quinovic acid, cincholic acid, cincholic 3 beta-O-6-deoxy-beta-D-glucopyranoside acid and quinovic 3 beta-O-beta-D-glucopyranoside acid were also isolated.