Cytotoxic isoquinoline Quinones from the Thai sponge Cribrochalina

Three isoquinoline quinones, (+)-N-formyl-1,2-dihydrorenierone (1), O-demethylrenierone (2), and mimosamycin (3), were isolated from the Thai purplish-blue sponge, Cribrochalina sp. The cytotoxicity against various cancer cell lines of the three compounds, determined employing the SRB method, was first reported here. It was found that all three were highly active, especially against MCF-7 breast carcinoma and HeLa cervical cancer cell lines. Also, this report is the first isolation of (+)-enantiomer of N-formyl-1,2-dihydrorenierone from a naturally occurring source.