Pulcherralpin, a new diterpene ester from Caesalpinia pulcherrima

From the stems of Caesalpinia pulcherrima, the new cassane-type diterpene ester pulcherralpin (1) has been isolated and characterized. The structure of 1 was established through spectroscopic studies, including the 1H-1H homonuclear and 1H-13C heteronuclear correlation studies.