DNA binding compounds. VII - Synthesis, characterization and DNA binding capacity of 1,2-dicarba-closo-dodecaborane bibenzimidazoles related to the DNA minor groove binder Hoechst 33258

A series of bibenzimidazole derivatives based on the known DNA minor groove binder Hoechst 33258 have been prepared to include a 1,2-dicarba-closo-dod ecaborane cage for potential use in boron neutron capture therapy (BNCT). T he carborane derivatives (5)-(7) were chosen to reduce the steric inhibitio n of minor groove DNA binding displayed by the previously prepared carboran e ligand (4). The synthesis and preliminary DNA binding studies of these bi benzimidazole derivatives are presented herein.