Covalent labelling at 5'-end of synthetic oligonucleotides by one step generation of alkylamino group

Abstract

Labelling of oligonucleotides can be carried out at 5'- and / or 3'-positions, phosphate backbone or nucleobases. The widely used labelling strategies, however, involve labelling of 5'- position where the label is covalently attached through a linker. Usually -NH₂ or -SH functionalities are generated for coupling of the reporter groups. In the present work, a rapid

one step procedure for generating 5'-alkylamino function has been developed.5'-Butylamino thymidine and 5'-butylaminod (TGCT) have been synthesised using solid phase synthesis. The efficacy of the method reported herein has been evaluated by labelling 5'- position with a fluorophore, 4-acetylamino-1, 8-naphthalimido-<i>N</i>-caproic acid (NCA).