IMIDAZOLE ALKALOIDS FROM THE INDOPACIFIC SPONGE PERICHARAX HETERORAPHIS

Abstract

Chem. investigation of the sponge Pericharax heteroraphis (Polejeff) collected in Indonesia, has led to the isolation of three imidazole alkaloids, preclathridine-A (1), leucettamine-B (2) and leucettamine-A (3). The structures of the isolated compds. were unambiguously established by 1D and 2D NMR and mass data. This is the first report of this class of compds. from the P. heteroraphis sponge. Investigation of the antimicrobial activities of the isolated compds. showed that leucettamine-A (3) was active against the gram-pos. bacteria Staphylococcus aureus and the fungus Cladosporium herbarum, while other compds. were inactive. [on SciFinder(R)]