Synthesis and in vitro testing of hematoporphyrin type ligands in platinum(II) complexes as potent cytostatic and phototoxic antitumor agents

We report on the synthesis and characterization of thirteen new porphyrin ligands and their platinum(II) complexes. All the porphyrin ligands derive from the naturally occurring hematoporphyrin, which plays an important role in the photodynamic therapy of different kinds of cancer. The combination of a platinum moiety and a porphyrin group in the same molecule results in a system which shows the cytostatic effect caused by the platinum fragment and the additional phototoxic effect on irradiation caused by the porphyrin ligand. We corroborate this double antitumor activity by extensive in vitro tests towards the MDA-MB-231 mammary carcinoma cell line. The data obtained confirm our idea of getting a twofold inhibition of cell growth bq the cytostatic platinum effect and by the phototoxic porphyrin effect. (C) 1997 Elsevier Science S.A.