This paper describes design and syntheses of a new class of chelator-type nucleic acid mimics. Four nucleic acid mimics 7, 11, 15, 17 possess a nucleobase and two ethylenediamine moieties for intermolecular metal coordination. We expected that chelator- type nucleic acid mimics formed a strand in the presence of metal ion and then interacted with a single-stranded DNA. Efficient synthetic routes leading to the four nucleic acid ...