Cytotoxic nor-dammarane triterpenes from Viburnum hainanense Merr. et Chun.

Five new nor-dammarane triterpenes, 12β-O-acetyl-17β-hydoxy-3,15-dioxo-20,21,22,23,24,25,26,27-octanordammanran (1), 12β-hydoxy-17β-methoxy-3,15-dioxo-20,21,22,23,24,25,26,27-octanordammanran (2), 12β-O-acetyl-3,15-dioxo-17-en-20,21,22,23,24,25,26,27-octanordammanran (3), 12β-hydoxy-15α-O-acetyl-3-oxo-17-en-20,21,22,23,24,25,26,27-octanordammanran (4) and 3β-hydoxy-17-oxo-12-en-20,21,22,23,24,25,26,27-octanordammanran (5), were obtained from the ethanol extract of the whole plants of Viburnum hainanense Merr. et Chun. Structural elucidation of all the compounds was performed by spectral methods such as 1D and 2D NMR, IR, UV, and HRESIMS. The isolated compounds were tested in vitro for cytotoxic potential against seven tumor cell lines (Hep-2, SCL-1, CAL-27, UMSCC-1, Detroit-562, SCC-PKU, and TCA-83). As result, compounds 1 and 2 exhibited cytotoxic activities with IC50 values less than 10 μM.