Lanostane triterpene glycosides from the flowers of Lyonia ovalifolia var. hebecarpa and their antiproliferative activities

The flowers of Lyonia ovalifolia var. hebecarpa were phytochemically investigated for the first time, leading the isolation of sixteen lanostane-type triterpene glycosides including eight new ones. The Mo2(OAc)4–induced electronic circular dichroism method was used to determine the absolute configurations of C-24 in lyonicarposides A (1), C (3), and E (5). All compounds were evaluated for their antiproliferative activities against five cancer and one normal cell lines. [Display omitted] •This is the first phytochemical studies on the flowers of L. ovalifolia var. hebecarpa.•Sixteen lanostane triterpene glycosides including eight new ones were isolated.•A Mo2(OAc)4–induced CD method was used to determine the absolute configuration of C-24.•All isolates were evaluated for their antiproliferative activities. Sixteen lanostane-type triterpene glycosides including eight new ones, named lyonicarposides A–H (1–8), were isolated from the flowers of Lyonia ovalifolia var. hebecarpa (Franch. ex F.B. Forbes & Hemsl.) Chun (Ericaceae). The chemical structures of the new compounds were elucidated by the comprehensive spectroscopic techniques and chemical methods. The Mo2(OAc)4–induced electronic circular dichroism method was used to determine the absolute configurations of C-24 in lyonicarposides A (1), C (3), and E (5). This is the first phytochemical study on the flowers of L. ovalifolia var. hebecarpa. All the isolates were evaluated for their antiproliferative activities against SMMC-7721, HL-60, SW480, MCF-7, and A-549 cell lines. Lyonicarposides A (1) and B (2) showed moderate antiproliferative activities against five cancer cell lines with IC50 values ranging from 12.39 to 28.71 μM. Lyonicarposides C (3) and G (7) and lyonifoloside M (12) selectively inhibited the proliferation of HL-60 and MCF-7 cell lines with IC50 values ranging from 13.03 to 17.71 μM. Interestingly, lyonifoloside L (13) selectively inhibited the proliferation of MCF-7 cell line with an IC50 value of 16.27 μM. Their structure-activity-relationships were discussed.