Isolation and characterization of new minor triterpenoid saponins from the buds of Lonicera macranthoides

Three new minor compounds, 18-oleanene (1), lupine (2), and 12-oleanene (3) type triterpenoid saponins, along with four major known triterpenoid saponins were isolated from the buds of Lonicera macranthoides. Their structures were elucidated by spectroscopic and chemical analyses. 18-oleanene and lupine-type triterpenoid saponins were first isolated from this plant. The isolated compounds were evaluated for their cytotoxic activities against HSC-2 cells.