Saxifraganoids A and B, two novel cucurbitane triterpenoid glycosides from Saxifraga umbellulata var. pectinata

Two novel cucurbitane triterpenoid glycosides, named saxifraganoids A (1) and B (2), were isolated from Saxifraga umbellulata var. pectinata. Their structures including absolute configurations were elucidated based on the analysis of spectroscopic data (1D, 2D NMR and HRMS), and single-crystal X-ray diffraction. Compound 1 represents the first example of cucurbitane triterpenoid with a Δ17(20), and compound 2 contained an unusual N-acetylglucosamine at C-16. The protective effects against liver injury induced by carbon tetrachloride (CCl4) in the human embryonic-liver L-02 cells of these two compounds were evaluated.