1 Department of Chemistry and Biochemistry, Faculty of Arts and Science, Concordia University, 7141 Rue Sherbrooke Ouest, Montréal, Québec H4B 1R6, Canada.

The synthesis and incorporation of a tosylated phosphoramidite linker containing a disulfide bond is described. Incorporation of the linker into short DNA and RNA oligomers proceeded efficiently using automated solid phase synthesis. Treatment of the support bound oligonucleotide followed by cleavage from the solid support provided a variety of common functional handles, expanding the strategies of bifunctional modification of synthetic oligonucleotides for conjugation applications.