Studies of Australian soft corals. XXIX. Several new cembranoid diterpenes from Nephthea brassica and related diterpenes from a Sarcophyton species

Abstract

The isolation of five known cembranoid diterpenes, (1), (2), (3), (4) and ( 5 ) , is reported from the soft coral Nephthea brassica. These diterpenes co-occur with several new but related diterpenes: (13S)-cembra-1,3,7,11-tetraen-13-ol (6) and its corresponding 13-acetate (7), 15-acetoxycembra-3,7,11-triene (8), (10S)-10,15-diacetoxy-7,8-epoxycembra-3,11-diene (9) and its corresponding 10-monoacetoxy derivative (10). Two related cembranoid diterpenes, (14S)-acetoxycembra-1,3,7,11-tetraene (15) and (14S)-cembra-1,3,7,11-tetraen-14-01 (16), are reported from a soft coral of the genus Sarcophyton.