The petroleum ether extract of the soft coral Sarcophyton decaryi yielded the cembrane-type diterpenes thunbergol (l), decaryiol (4), and 3, 4-epoxynephthenol (13) in addition to nephthenol and trocheliophorol as reported previously. Compounds 4 and 13 are new and were characterized by spectral data, degradative studies by ozonolysis, and chemical transformations. Nephthenol reacts eth tetrabromocyclohexadienone to give 11, the 3- ...