[New triterpenoids saponins from Helianthus annuus]

Three new bisdesmosidic triterpenoid saponins, helianthoside 1(1), 2(2), and 3(3), were isolated from the flowers of Helianthus annuus L. and a new monodesmoside 4 was isolated after the cleavage of the ester-glycosidic linkages of 2 and 3. The structures of the compounds were elucidated by 13C-NMR, FAB-MS, GC/EI-MS of partially methylated alditol acetates and degradation methods.