Studies of Australian soft corals. XXVII. Two novel diterpenes from Sarcophyton glaucum

Abstract

The soft coral Sarcophyton glaucum is shown to contain two cembranoid diterpenes (1) (1Z,5S,9E,11E)-5,9-dimethyl-12-isopropyl-6-oxocyclotetradeca-1,9,11-triene-1,5-carbolactone, and its related 6R-hydroxy derivative (2). The broad structural features were deduced spectroscopically and confirmed by chemical conversion and degradation. Stereochemistry was elucidated by comparison with the known diterpene emblide (3) also reported from S. glaucum.