the corresponding diiodoplatinum ii complexes synthesis of the platinum complexes reaction of the porphyrin carboxylic acids with cisplatin did not result in the desired complexes therefore cisplatin had to be activated by conversion into diammine diaqua platinum ii hydroxide which was reacted with an equimolar amount of the porphyrin ligand in a mixture of ethanol and water or in the case of the water soluble ligands in pure water the resulting diammine dicarboxylato platinum ii complexes precipitated to the reaction mixtures of the water soluble complexes ch 2 cl 2 was added to remove neutral impurities before the aqueous phase was evaporated to obtain the products the diamine dichloro platinum ii precursors were activated by conversion into diamine dihydroxy platinum ii species which were reacted with an equimolar amount of the respective porphyrin carboxylic acid in a mixture of ethanol and water or in the case of the water soluble ligands in pure water the complexes precipitated to the water soluble complex ch 2 cl 2 was added to remove neutral impurities and the aqueous phase was evaporated to obtain the product for the reaction with the porphyrincarboxylic acids it is necessary to activate the diamine diiodo platinum ii complexes by conversion into diamine dinitrato platinum ii species which are water soluble in this form they were reacted with an equimolar amount of the porphyrin ligand in a mixture of ethanol and water or in the case of the water soluble ligand in pure water the water insoluble complexes precipitated after concentrating the solution the water soluble complexes were isolated by chromatography on silica the following examples are intended to explain the invention in more detail the inventive compounds are tetraarylporphyrin platinum derivatives covered by way of example by.