Intramolecular migration of co-ordinated platinum from a sulfur to N7 in the nucleopeptide Met-d(TpG) (5′-O-methioninate-N-ylcarbonylthymidine 2′-deoxyguanosine monophosphate)†

The nucleopeptide Met-d(TpG) (5′-O-methioninate-N-ylcarbonylthymidine 2′-deoxyguanosine monophosphate), containing a methionine moiety covalently linked to a TpG dinucleotide, upon reaction with platinum complexes, initially yielded platinum co-ordination to the sulfur atom, which subsequently is substituted by the N7 atom of guanine for the reaction with monofunctional [Pt(dien)Cl]Cl (dien = diethylenetriamine); in the case of the cisplatin analogue [Pt(en)Cl2] (en = ethane-1,2-diamine) formation of a stable S,N chelate takes place.