Nucleic acid analogues: Synthesis and biomimetic reactions

Several nucleic acid analogues as shown in Scheme 1 were synthesized by alternating copolymerization of nucleoside analogues with maleic anhydride or acrylic anhydride. These polymers showed similar physicochemical properties to those of the natural polymers, such as base-pairing and base-stacking, Polymer 3U, for example, formed 1:1 complex with poly(adenylic acid) by base-pairing. Polymer 4A showed 33 % of hypochromicity compared with the UV-absorption of adenosine due to the base-stacking. Polymer 5 catalyzed the cleavage of DNA and the hydrolysis of phosphodiester with a rate acceleration of 10(3) compared with the uncatalyzed reaction.