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The [Pd(AEMP)Cl2] complex [AEMP = 2-(2-aminoethyl)-1-methylpyrrolidine] was prepared and characterized by single-crystal X-ray diffraction and spectroscopic analyses. The structure of the complex was found to be square-planar with some distortion. The geometric optimizations of the ligand and complex were performed with the DFT/B3LYP method by using Gaussian 09. The stoichiometry and stability constants of the complexes formed in the reaction of [Pd(AEMP)(H2O)2]2+ with dicarboxylic acids and DNA constituents were investigated at 0.1 m ionic strength and 25 °C. The results show that both DNA constituents and cyclobutanedicarboxylate (CBDCA) coordinate to [Pd(AEMP)(H2O)2]2+ to form the quaternary complex [Pd(AEMP)(CBDCA-O)DNA], where CBDCA-O represents cyclobutanedicarboxylate coordinated through one carboxylate oxygen atom to the PdII center. The speciation concentration distributions in solution were evaluated. The biological activity for DNA cleavage and cytotoxicity of the [Pd(AEMP)Cl2] complex was studied. [ABSTRACT FROM AUTHOR]

Amino acid esters (L) react with [Pd(Eten)(H 2 O) 2 ] 2+ (Eten = N -ethyl ethylenediamine) giving mixed ligand complexes of the type [Pd(Eten)L] 2+ . Base hydrolysis of [Pd(Eten)L] 2+ was studied by pH-stat technique from which rate constants for the base hydrolysis of the esters were obtained. The glycine methyl ester hydrolysed significantly, whereas the methionine methyl and histidine methyl esters hydrolysed much slower. The mode of coordination of the ester plays a role in the catalysis, and possible mechanisms for these reactions are considered. Activation parameters were determined for the hydrolysis of the glycine methyl ester. The effect of the dielectric constant of the medium on the hydrolysis process was also investigated. The B3LYP/LANL2DZ method was used for geometric optimization of the free ligand and the complex using the Gaussian 09 program. The calculations are compared with the kinetic data. In addition, the vibrational frequencies of the molecules were computed for the optimized geometries. [ABSTRACT FROM AUTHOR]