TERNARY COMPLEXES OF CIS-PT(NH3)(2)CL-2 AND TRANS-PT(NH3)(2)CL-2 (CIS-DDP, TRANS-DDP) WITH 9-METHYLGUANINE (9-MEG), THE DIPEPTIDES GLYCYLGLYCINE (GLYGLY), GLYCYL-L-ALANINE (GLYALA), GLYCYL-L-2-AMINOBUTYRIC ACID (GLY-2-ABA), GLYCYL-L-NORCRALINE (GLYNVAL), GLYCYL-L-NORLEUCINE (GLYNLEU), AND OF TRANS-PT(NH3)(2)CL-2 WITH NA-L-ACETYLHISTIDINE

The reactions of cis- and trans-[(NH3)(2)Pt(9-MeG)X]Y (X=Cl, H2O; Y=Cl , NO3, BPh(4)) with the dipeptides glygly, glyala, gly-2-aba, glynval and glynleu, and of trans-[(NH3)(2)Pt(9-MeG)X]Y with the sodium salt o f Na-L-acetyl-histidine in aqueous solutions, produced the analyticall y pure ternary complexes cis- and trans-[(NH3)(2)Pt(9-MeG)(glygly)]Y-n , (n=1, 2) (1A, 1B), cis- and trans-[(NH3)(2)Pt(9-MeG)(glyala)]Y-n, (2 A, 2B), cis- and trans-[(NH3)(2)Pt(9-MeG)(gly-2-aba)]Y-n (3A, 3B), cis - and trans[(NH3)(2)Pt(9-MeG)(glynval)]Y-n (4A, 4B), cis- and trans-[( NH3)(2)Pt(9-MeG)(glynleu)]Y-n (5A, 5B) and trans-[(NH3)(2)Pt(9-MeG)(ac his-N-1,N-3)](NO3). These were characterized in the solid state with e lemental analysis, IR, H-3 NMR and (195)pt NMR spectra. 9-MeG retains its N-7 coordination in the ternary complexes. Hydrophobic intramolecu lar ligand-ligand interactions were detected in the cis-ternary system s with H-1 NMR spectra, between 9-MeG and the dipeptides, increasing w ith the length of the aliphatic side chain of the latter. These were m uch weaker in the trans series, and might be of intermolecular nature. The trans-[(NH3)(2)Pt(9-MeG)(achis-N-1)]NO3 and trans-[(NH3)(2)Pt(9-M eG)(achis-N-3)](NO3) contained achis coordinated through the N-1 and N -3 atoms in a ratio of 0.8.