A new cassane diterpenoid, caesaldecan, was isolated from Caesalpinia decapetala with eight known compounds, spathulenol, 4,5-epoxy-8(14)-caryophyllene, squalene, lupeol, trans-resveratrol, quercetin, astragalin, and stigmasterol. The 1H- and 13C-NMR spectra of the new compound were completely assigned by using a combination of 2D NMR techniques, namely, 1H–1H COSY, HMQC, HMBC, and ROESY.
