THE NATURAL POLYPROPIONATE-DERIVED ESTERS OF THE MOLLUSK ONCHIDIUM SP

Eight new polypropionate-derived esters (5-8 and 10-13) have been isolated from pulmonate molluscs of the genus Onchidium collected in the South Pacific. The structures of these compounds were determined spectroscopically in particular by one- and two-dimensional NMR and low and high EIMS. The absolute of the seven asymmetric centers was determined by using the Trost-Mosher methodology. Saponification afforded two triols named onchitriol I and II (4 and 9, respectively). Compounds 4-13 displayed in vitro antitumor activity against several cell lines. Onchitriol I and II had antiviral activity also.