Post-synthetic introduction of labile functionalities onto purine residues via 6-methylthiopurines in oligodeoxyribonucleotides

Article abstract of DOI:10.1016/0040-4020(96)00596-0

Two methods are described for the preparation of oligodeoxynucleotides containing 6-methylthiopurine residues. 6-Methylthiopurine phosphoramidite (6) has been prepared and incorporated into oligomers. Methylation with methyl iodide of 6-thiopurine (or 6-thioguanine) in oligomers also exclusively produces oligomers containing 6-methylthiopurine (or 6-methylthioguanine). The methylthio group at defined purine residues in the deprotected oligomers can be oxidized selectively and converted at the final step into various functional groups including radioactive ³⁵S-thio group, a useful tag for cross-linking studies.