Oligomers with Intercalating Cytosine–Cytosine+ Base Pairs and Peptide Backbone: DNA i-Motif Analogues

Alanyl peptide nucleic acids organize in a similar manner to the DNA structure motif by stabilizing two cytosine–cytosine⁺ pairing double strands by intercalation (i-motif). These analogues demonstrate that a tetrameric arrangement of nucleobases is necessary for C–C⁺ pairing (see diagram), whereas formation of the i-motif does not depend on the ribosyl–phosphodiester backbone.