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-dodecaborane cage for potential use in boron neutron capture therapy (BNCT). The carborane derivatives (5)-(7) were chosen to reduce the steric inhibition of minor groove DNA binding displayed by the previously prepared carborane ligand (4). The synthesis and preliminary DNA binding studies of these bibenzimidazole derivatives are presented herein.