Hebecarposides A-K, antiproliferative lanostane-type triterpene glycosides from the leaves of Lyonia ovalifolia var. hebecarpa.

Eleven previously undescribed lanostane-type triterpene glycosides, hebecarposides A-K, were isolated from the leaves of Lyonia ovalifolia var. hebecarpa (Ericaceae), along with two known analogues, lyonifolosides L and O. The structures of hebecarposides A-K were established by extensive spectroscopic analysis and chemical methods, and the absolute configuration of C-24 in hebecarposides A and E was determined to be S and R, respectively, by a Mo(OAc)-induced electronic circular dichroism method. This is the first report of the presence of lanostane-type triterpene glycosides in L. ovalifolia var. hebecarpa. All compounds were evaluated for their antiproliferative activities against five cancer cell lines, SMMC-7721, HL-60, SW480, MCF-7, and A-549, and a normal epithelial cell line BEAS-2B, and none of them showed general cytotoxity to the normal cell line BEAS-2B. Interestingly, hebecarposides C, D, G, and K selectively inhibited the proliferation of HL-60 and SMMC-7721 cell lines, and hebecarposides C and D showed significant anti-proliferative activities against A-549 cell lines than the positive control, cis-platin. In addition, hebecarposides C and H exhibited more potent anti-proliferative activities against MCF-7 than cis-platin.