Oxytoxins,bioactive molecules produced by the marine opisthobranch molluscOxynoe olivacea from a diet-derived precursor

Summary The ethereal extract of the mucous secretion from the opisthobranch molluscOxynoe olivacea was examined and found to contain two novel ichthyotoxic compounds, named oxytoxin 1 and 2 (1, 2). The structures of1 and2 are closely related to the metabolites previously isolated from the algaCaulerpa prolifera. The activity of the most stable compound was studied in order to investigate the possibility, of a further biological role for these metabolites, which represent an uncommon example of bioactive molecules produced in vivo from a dietary precursor.