Triterpenoid Saponin and Lignan Glycosides from the Traditional Medicine Elaeagnus angustifolia Flowers and Their Cytotoxic Activities

A new triterpenoid saponin, named terpengustifol A (1), and two new lignan glucosides, phengustifols A and B (2 and 3), were isolated from the flowers of Elaeagnus angustifolia. Their structures were determined by the extensive analysis of the spectroscopic data (including NMR and HRMS) and ECD calculations. Compound 1 possesses an unusual monoterpene (Z)-6-hydroxy-2,6-dimethylocta-2,7-dienoyl unit at C-21. Compounds 2 and 3 are a pair of diastereoisomers, while their aglycones are a pair of enantiomers. Compounds 1 and 2 exhibited moderate cytotoxic activities against A375 cell lines with IC50 values at 12.1 and 15.6 &mu
M, respectively. This is firstly reported the triterpenoid saponin and lignans isolated from the Elaeagnus angustifolia flowers.