A specimen of Lobophytum cristigalli
collected in Sri Lanka afforded two cembranolide
diterpenes
(7E,11E,1R,2S,3R,4R,14S)-14-acetoxy-3,4-epoxycembra-7,11,15-trien-17,2-olide
(6)* and the corresponding alcohol (7). Their structures were deduced
spectroscopically and detailed stereochemistry of (6)
was determined by X-ray crystallography.