Cassane-type diterpenoids from the seed kernels of Caesalpinia bonduc

Abstract

Seven new cassane diterpenoids (1–7), along with three known compounds (8–10), were isolated from the seed kernels of Caesalpinia bonduc. The structures were elucidated by extensive 1D and 2D NMR (HSQC, HMBC and ROESY) and mass (HRESIMS) spectroscopic data analyses. The structure and absolute configuration of compound 1 were confirmed by a single-crystal X-ray diffraction experiment. All isolates were tested for their cytotoxicity against HepG-2, MCF-7 and MG-63 cells, and 8–10 showed weak inhibitory activities.