Some mixed-ligand palladium(II) complexes of 2,2'-bipyridine and amino acids as potential anticancer agents

Eight new palladium complexes of the formula [Pd(bipy)(AA)]Cl 1 or 2 H2O (where bipy is 2,2'-bipyridine and AA is an anion of glycine, L-alanine, L-leucine, L-proline, L-serine, L-lysine, L-asparagine, or L-glutamine) have been synthesized by reaction of [Pd(bipy)Cl2] with an appropriate mono sodium salt of amino acid in water. These complexes have been characterized by chemical analysis and by visible, infrared, and 1H NMR spectroscopy. The detailed 1H NMR and infrared spectral studies of these complexes ascertain the mode of binding of amino acids to palladium through nitrogen of terminal -NH2 group and oxygen of terminal -COO- group. The molar conductance values of these complexes in water suggest them to be 1:1 electrolytes. These complexes have also shown growth inhibition against L1210 lymphoid leukemic, P388 lymphocytic leukemic, Sarcoma 180, and Ehrlich ascitic tumor cells. Some of these complexes show better 50% inhibitory dose values than cis-diamminedichloroplatinum(II).