Recognition of DNA with assembly of minor groove binders mediated by metal complexation.

Genome-targeting molecules would have broad application as probes in genomic study. We recently developed the ligands (Bpy-H) connecting the Hoechst33258 skeleton for DNA binding and 2,2'-bipyridine for Cu(2+) complexation. It was shown that L-Bpy-H with a long linker exhibited Cu(2+)-mediated assembly on the DNA template having two A(3)T(3) sites in a ratio of 1:2:1 DNA-ligand-Cu(2+). Binding selectivity depends on the distance between the two A(3)T(3) sites of DNA. In contrast, S-Bpy-H having a short linker tended to form 1:2:2 DNA-ligand-Cu(2+) complex.