Two new triterpenoid saponins from the flowers and buds of Lonicera japonica

Two new triterpenoid saponins, loniceroside D (1) and loniceroside E (2), were isolated from the dry flowers and buds of Lonicera japonica Thunb., along with seven known compounds, chlorogenic acid (3), sweroside (4), vogeloside (5), epi-vogeloside (6), loniceroside A (7), loniceroside B (8), and loniceroside C (9). Their structures were elucidated on the basis of spectroscopic data, physicochemical properties, and acid hydrolysis.