Two diterpenes, epipolone (1) and epipolol (3), produced by terpenoid pathw
ays leading to a tricarbocyclic structure with an irregular "head to tail"
isoprene configuration, have been isolated from the Caribbean marine sponge
Epipolasis reiswigi collected in Puerto Rico. The structures of I and 3 we
re elucidated largely by ID and 2D NMR methods land chemical conversion.