TERNARY COMPLEXES OF PT(II) WITH GUANOSINE AND AMINO-ACIDS OF THE TYPE TRANS-[(GUO)2PT(AMACH)2]CL2, WHERE AMACH IS GLYCINE, L-ALANINE, L-VALINE, AND L-ISOLEUCINE

The complexes of the general formulae trans-[(guo)2Pt(amacH)2]Cl2 with amacH = Glycine, L-Alanine, L-Valine, and L-Isoleucine, were isolated as solid adducts from the reactions of trans-[(amacH)2PtCl2] with guo in aqueous solutions. The complexes were characterized with elemental analysis, conductivity measurements, IR, and H-1 NMR spectra. Guo coordinates through N(7) and the amino acids through their-NH2 groups. Two groups of proton signals for the amino acid protons were observed in the H-1 NMR spectra, due to their participation to nonequivalent hydrogen bonds. Ligand-ligand hydrophobic interactions were detected in the complexes. The various sugar conformations of guo were calculated, based on H-1 NMR and the results were discussed in relation to DNA-Pt-protein crosslinks, taking place with cis- and trans-DDP.