Cytotoxic Phosphinoarsino and Diphosphino Pd(II) Complexes of Thiolate Amino Acids and Glutathione.

The novel complexes [Pd(L-L′)(SR)Cl] where L-L′ is Ph2PCH2CH2PPh2 (dppe) or Ph2AsCH2CH2PPh2 (dadpe) and RSH is glutathione, L-cysteine, or N-acetyl-L-cysteine, have been prepared and characterised. Their structures in the solid-state and in solution are discussed. The introduction of cysteine or glutathione as a ligand in these complexes greatly improved their aqueous solubility compared with the hydrophobic parent dichloro complexes. The cytotoxicities of the glutathione complexes towards the cell-lines L1210, ADJ/PC6 and CH1 were investigated. Their cytotoxicities towards L1210 cells were comparable to those of the parent dichloro complexes.