Polyacetylenic Oleanane-Type Triterpene Saponins from the Roots of Panax japonicus

Three new polyacetylenic oleanane-type triterpenoids, baisanqisaponins A–C (1–3), and one new oleanane-type triterpenoid, chikusetsusaponin-V ethyl ester (4), together with 19 known compounds (5–23), were isolated from the roots of Panax japonicus. The structures were elucidated on the basis of spectroscopic analyses and chemical methods. Compounds 1–3 feature a rare panaxytriol group containing a polyacetylene on the saponin skeleton. Neuroprotective activity was evaluated for compounds 1–17, and angiotensin II-induced vascular smooth muscle cell proliferation inhibition was tested for compounds 5–7 and 10–12.