New Cassane-Type Diterpenoids from Caesalpinia bonduc

Abstract

Six new cassane diterpenoids, named caesalls H–M (1–6), were isolated from the seed kernels of Caesalpinia bonduc. Their structures were elucidated on the basis of spectroscopic analysis, mainly NMR and MS. The absolute configurations of compounds 1 and 3 were determined by a single-crystal X-ray study using a mirror CuKα radiation and circular dichroism (CD) spectra, respectively. None of the compounds were cytotoxic against HepG-2, MCF-7 and MG-63 cells.