PENTACYCLIC TRITERPENOID SAPONIN FROM CYCLAMEN COUM

A new triterpenoid saponin, coumoside B, has been isolated from the wh ole plant of Cyclamen coum. The structure of the compound 3 (C58H92O27 ) has been deduced by NMR (400 MHz) methods based on the H-1,C-13, DEP T, H-1-H-1 COSY, HETCOR, NOESY-NMR experiments, and FAB-mass spectrum. Compound 3 was shown to have the structure 16 alpha-hydroxy-3 beta-{{ [[beta-xyropyranosyl-(1 --> 2)]-[beta-glucopyranosyl-(1 --> 4)]-[beta- glucopyranosyl-(1 --> a-arabinopyranosyl}-oxy}olean-12-eno-30,28-lacto ne and is named coumoside B.