The preparation and characterisation of some aminesulfoxidedichloroplatinum(II) complexes

Abstract

A series of compounds designed to bind to GpA sequences of DNA has been prepared and characterised. Procedures have been developed for the syntheses of [Pt{MeS(O)CH₂CH₂NH₂}Cl₂]1 and (2S,SR)- and (2S, SS)–[Pt{MeS(O)CH₂CH₂CH(CO₂Me)NH₂}Cl₂]2a, 2b. The crystal structures of 1 and of the two diastereomers, 2a and 2b, have been determined. Crystals of 1 are orthorhombic, space group Pcab, a= 9.405(1), b= 10.847(1), c= 16.170(1)Å, Z= 8, R= 0.30 for 1410 reflections. Crystals of 2a are orthorhombic, space group P2₁2₁2₁, a= 9.738(1), b= 10.588(1), c= 11.090(1)Å, Z= 4, R= 0.021 for 1382 reflections. Crystals of 2b are orthorhombic, space group P2₁2₁2₁, a= 10.977(3), b= 13.738(9), c= 25.24(1)Å, Z= 12, R= 0.078 for 1482 reflections. Energy minimisation calculations have been used to develop a force field for a series of dichloroplatinum(II) sulfoxide complexes.