Cembranoid diterpenes and a briarane diterpene from corals

Abstract

Two new cembrane diterpenes (+)-polydactylide (1) and (+)-7α,8β-dihydroxydeepoxysarcophine (2) together with (+)-sarcophine (3) and (+)-sarcophytoxide (4) have been isolated from the soft coral Sinularia polydactyla. The new cembrane diterpene (−)-7β-hydroxy-8α-methoxydeepoxysarcophine (5) has been obtained from the soft coral Sarcophyton trocheliophorum and the known briarane diterpene briaexcavatolide W (6) from the gorgonian coral Briareum sp. The structures were determined primarily by NMR spectroscopy. The assignment of NMR signals was performed by means of 1H–1H COSY, ROESY, HMQC and HMBC experiments.