Synthesis of alkyne- and azide-modified oligonucleotides and their cyclization by the CuAAC (click) reaction

Abstract

The Cu(I)-catalyzed alkyne-azide cycloaddition (CuAAC) reaction has been used to synthesize cyclic mini-DNA duplexes. The reaction is carried out on 5'-alkyne-3'-azide-labeled hairpin loop oligonucleotides and proceeds in high yield under mild conditions in as little as 5 min. The resultant duplexes have very high thermal stability and their CD spectra are characteristic of normal B-DNA.