ALKYL ESTER DERIVATIVES OF METHIONINE AND HISTIDINE WITH PD(II) AND PT(II)

Several methionine and histidine alkyl (Me, Et, and i-Pr) ester Pd(II) and Pt(II)complexes were prepared and characterized by elemental analyses, IR and H-1 and C-13 NMR spectroscopies. The X-ray structure of [PdCl2(L-MetOMe)] shows the slightly distorted square-plane coordination of the metal ion to the sulphur atom and aminic nitrogen of the methionine ester and to two chlorines. The reaction of [PdCl2(L-MetOMe)], [PtCl2(L-MetOMe)], and [PdCl2(L-HisOMe)] with the nucleotides 5'GMP and 5'CMP gave ternary complexes with the formulae Na-2[M(Nucleotide)(2)(Amino acidOMe)]. In all the reactions, the two chloride ions bound to the metal ion in the binary compounds were substituted by two molecules of nucleotide while the methyl ester amino acid remained coordinated to the metal ion by thioether S or imidazolic N and NH2 group.