Abstract
A procedure is described for the purification of synthetic methylphosphonate oligodeoxyribo-nucleosides. Syntheses were done on an automated instrument with the trityl group on in the last cycle. The oligomers were manually cleaved from the solid support and purified by reverse-phase HPLC in order to remove shorter fragments produced during incomplete couplings. After detritylation, the oligomers were repurified by reverse-phase HPLC. Typically, an overall yield of 25% or more was obtained.