Ileabethin: isolation and structure of a new class of perhydroacenaphthene diterpene from the Caribbean Sea Whip Pseudopterogorgia elisabethae (Bayer)

A recent chemical investigation of the hexane extract of a Colombian specimen of Pseudopterogorgia elisabethae (Bayer) has led to the isolation of ileabethin (1). This novel diterpene possesses a previously undescribed carbon skeleton which appears to be biosynthetically related to the serrulatane (biflorane) skeleton. The structure of 1 was elucidated after interpretation of its combined spectroscopic data.