A convenient ‘click chemistry’ approach to perylene diimide–oligonucleotide conjugates

Terminal alkyne-containing phosphoramidite and solid support were prepared and used for the synthesis of 5′- and 3′-alkyne-modified oligonucleotides. The copper-catalyzed Huisgen [3+2] cycloaddition reaction in water–DMSO was used for the efficient preparation of perylene diimide–oligonucleotide conjugates suitable for constructing various types of PDI-modified DNA duplexes.