Synthesis of polyamine-containing oligonucleotides

A simple and efficient method of synthesis of polyamine-oligonucleotide conjugates (PA-oligos) in high yields (up to 95%) was suggested. The terminal phosphate group of deprotected oligonucleotides was selectively activated with the redox pair triphenylphosphine-dipyridyl disulfide in the presence of a nucleophilic catalyst, and the activated oligonucleotide derivative was subjected to the reaction with a polyamine.