Massarinolins A-C (1-3), three new bioactive sesquiterpenoids possessing ra
re ring systems, have been isolated from liquid cultures of the aquatic fun
gus Massarina tunicata Shearer & Fallah. The structures were determined pri
marily by analysis of NMR data. Metabolites 1-3 are the first compounds to
be reported from any member of the genus Massarina.