Targeted binding of a platinum(II)-methionine complex to the disulfide linkage of a nonapeptide oxytocin

Platinum(II)-methionine complex [Pt(Met)Cl2] preferentially binds to the disulfide bond between Cys1 and Cys6 residues of oxytocin, forming five- or six-membered chelates [Pt(Met)(OT)]Cl2 as the major products.