SOLID-PHASE SYNTHESIS OF OLIGODEOXYNUCLEOTIDES CONTAINING 3′-S-PHOSPHOROTHIOLATE LINKAGES

Abstract

For the first time a fully automated procedure has been developed for the incorporation of a 3′-S-phosphorothiolate linkage into DNA, using phosphorothioamidite monomers. Coupling yields with either of the activators 5-ethylthiotetrazole or 4,5-dicyanoimidazole were in the range of 80–90%. Coupling yields were equally good when performed on either a 0.2 or 1 μmole reaction column, thus facilitating large scale synthesis.

ACKNOWLEDGEMENTS

We would like to thank the EPSRC for generous support to KJF and are grateful to the EPSRC service at Swansea for obtaining mass spectra.