Induction of a Four-Way Junction Structure in the DNA Palindromic Hexanucleotide 5'-d(CGTACG)-3' by a Mononuclear Platinum Complex

Four-wayjunctions (4WJs) are supramolecular DNA assemblies comprising four interacting DNA strands thati n biology are involved in DNA-damagere pair.In this study,a new mononuclear platinum(II) complex 1 was prepared that is capable of drivingt he crystallization of the DNA oligomer5’-d(CGTACG)-3’ specifically into a 4WJ-like motif. In the crystal structure of the1–CGTACG adduct, the distorted-square-planar platinum complex binds to the core of the 4WJ-like motif through p–p stacking and hydrogen bonding,without forming any platinum–nitrogen coordination bonds.Our observations suggest that the specific molecular properties of the metal complex are crucially responsible for triggering the selective assembly of this peculiar DNA super-structure.