Synthesis of DNA‐Sequence‐Selective Hairpin Polyamide Platinum Complexes

Two DNA‐sequence‐selective hairpin polyamide platinum(II) complexes, containing pyrrole and imidazole heterocyclic rings, have been synthesised by different methods. A six‐ring complex, selective for (A/T)GGG(A/T) DNA sequences, was made by using solid‐phase synthesis, whilst an eight‐ring complex, selective for (A/T)CCTG(A/T) DNA sequences, was made by utilising standard wet chemistry. Solid‐phase synthesis resulted in a significantly higher yield, required less purification and is more efficient than the wet synthesis; as such, it is the preferred method for further work. The metal complexes were characterised by 1 H and 195 Pt NMR spectroscopy and ESI mass spectrometry. The two compounds provide a foundation for the synthesis of more complex molecules containing multiple hairpins and/or platinum groups.