New cucurbitane-type triterpenoid glucosides from the tubers of Hemsleya amabilis with anti-tumor activity

Two new cucurbitane-type triterpenoid glucosides, 3β,11α-dihydroxycucurbita-5,24(E)-diene-3,26-glucosides (1) and 3β,11α-dihydroxycucurbita-5,24(Z)-diene-3,27-glucosides were isolated from the tubers of Hemsleya amabilis. Their structures were elucidated by various spectroscopic techniques including IR, HRESIMS, 1D and 2D NMR. The two compounds were evaluated for their anti-tumor activity against HeLa and HepG-2 cell lines, and both displayed moderate anti-tumor activity towards HeLa cell lines with IC50 values of 9.8 and 15.7 μM, respectively.