Studies of Australian soft corals. IX. A novel nor-diterpene from the soft coral Sinularia leptoclados

Abstract

The structure of a novel nor-cembranoid diterpene of formula C₁₉H₂₄O₆ (1) is reported. The compound was extracted from the soft coral Sinularia leptoclados, and spectroscopic data were collected on the parent compound (1) and a series of derivatives. It was not possible to assign an unambiguous structure on purely spectroscopic grounds, and so single-crystal X-ray analysis was used to prove the structure (1): (4R*,8S*,11R*,13S*,14R*)-14-hydroxy-4-isopropenyl-11-methyl-6,9-dioxo-8,11-epoxycyclotetradec-1-ene-1,13-carbolactone.