Multivalent Metallosupramolecular Assemblies as Effective DNA Binding Agents

We report the implementation of coordination chemistry onto the generation of new types of metallosupramolecular complexes with laterally appended cationic moieties for DNA binding in buffered aqueous media. Utilization of an N,N,O-type coordination pocket along with an octahedral zinc(II) metal ion allowed us to obtain mono- and tetranuclear complexes in both solution and solid state, as confirmed by NMR spectroscopy and single-crystal X-ray diffraction, respectively. By using isothermal titration calorimetry and gel electrophoresis, multiply charged cationic assemblies were observed to effectively bind to DNA through multivalent electrostatic interactions. Furthermore, we observed a correlation between the multivalency of the compounds employed and the effectiveness of DNA binding.