abstract
- By use of bioassay (murine P388 lymphocytic leukemia cell line) guided isolation procedures, extracts of the Republic of Singapore marine sponge Hymeniacidon sp. were found to contain demethyloxyaaptamine (1) and aaptamine (3) as prominent cancer cell growth inhibitory constituents accompanied by the trace, albeit more active, component isoaaptamine (4). The isolation, X-ray structure elucidation, and antineoplastic and antimicrobial activities of isoaaptamine (4) have been summarized. Because of instability, isoaaptamine (4) was converted to a stable sodium phosphate prodrug designated hystatin 1 (7).