Antiplasmodial and cytotoxic metabolites from the Maltese sponge Agelas oroides.

From a Maltese sample of the marine sponge Agelas oroides, five compounds: oroidin (1), 2-cyano-4,5-dibromopyrrole (2), 4,5-dibromopyrrole-2-carboxylic acid (3), 4,5-dibromopyrrole-2-carboxylic acid methyl ester (4), and 4 alpha-methyl-5 alpha-cholest-8-en-3 beta-ol (5) have been isolated. For compounds 1-5, completely assigned 1H- and 13C-NMR data are reported for the first time. For 2 a single crystal X-ray crystallographic analysis proved its structure unambiguously. The X-ray analysis of 2 indicated it to crystallise in an unexpected polar space group. Biological activity assessment of all isolates indicate 5 to have moderate antiplasmodial activity, as well as being cytotoxic, and 2 to be moderately cytotoxic towards several cancer cell lines.