Triterpene saponins with neuroprotective effects from the leaves of ce:italic>Diospyros kaki/ce:italic> Thunb

摘要

Seven undescribed triterpene saponins, named kakisaponin I-VII (1–7), together with nine known ones (8–16) were isolated from the leaves ofDiospyros kakiThunb. by various chromatographic methods. Compounds1–5were novel 18, 19-secoursane triterpenoids, which were an uncommon type of triterpenoids. Their structures were elucidated by different spectroscopic methods, combining HRESIMS, 1D and 2D NMR. All isolated compounds were evaluated for their protective effects on H2O2-induced damage in human dopaminergic neuroblastoma cells (SH-SY5Y). Compound2showed significant neuroprotective effect at a certain concentration, and compounds3and12exhibited moderate bioactivities. Current study suggests that triterpene saponins inDiospyros kakimay play an important role in the neuroprotective properties.