Synthesis and photocytotoxic activity of new alpha-methylene-gamma-butyrolactone-psoralen heterodimers.

The synthesis of a new alpha-methylene-gamma-butyrolactone-psoralen heterodimer 2 is reported. Its photoantiproliferative activity and skin phototoxicity were compared with that of 5-methoxypsoralen (5-MOP) and another heterodimer 1. Both derivatives show a significant phototoxicity toward malignant cell lines including melanoma cells A375 compared to their intrinsic cytotoxicity in the dark. Both compounds were found to be nonphototoxic on mice skin and therefore could be active potential drugs in photochemotherapy.