Chemical investigation of the Mediterranean ascidian Ciona edwardsii has been performed, leading to the isolation of two halogenated compounds: a new tyrosineiodinated derivative iodocionin (1) and the relevant brominated analogue (2), previously isolated from a Caribbean sponge. The structure of the new compound 1 has been assigned on the basis of spectroscopic analysis. Both compounds were tested for cytotoxicity in vitro against two different cancer cell lines, L5178Y (mouse lymphoma) and PC-12 (rat pheochromocytoma). Iodocionin was shown to possess significant and selective activity against lymphoma cells with an IC(50) of 7.75 microg/mL.
Keywords: cytotoxic activity; iodinated metabolites; natural products; structure elucidation.