LAUSR

Pd(AEMP)Cl2 complex, where AEMP1⁄4 2-(2-aminoethyl)-1methylpyrrolidine was synthesized and characterized. The coordination of [Pd(AEMP)(H2O)2]2þ with ligands of biosignificance as DNA constituents, peptides and amino acids having different functional groups was investigated. The present study described the formation equilibria of binary and binuclear Pd(AEMP)(H2O)22þ complexes with some selected DNA constituents, peptides and amino acids. 4,4’-bipipridinewas used as a linker. Amino acids form 1:1 complexes. The stability constant is depending on the type of functional groups. Peptides form 1:1 complexes followed by induced ionization of the amide group. The potentiometric data of the binuclear complexes revealed the formation of [H2O(AEMP)PdBip-Pd(AEMP)H2O]4þ complex. The reaction of the latter complex with DNA constituents showed the formation of the 1:1 and 1:2 complexes by substitution of the two coordinated water molecules. The stability constant of the binuclear thymine complex formed with [H2O(CH3)2NCH2CH2NH2)Pd-Bip-Pd((CH3)2NCH2CH2NH2) H2O]4þ is in good agreement with that of the binuclear inosine complex formed with [(H2O)(AEMP)Pd(Bip)Pd(AEMP)(H2O)]4þ.The formation constant of all possible biand mononuclear complexes