Step/atom efficient. The preparation of nucleobase-modified nucleosides typically requires a multi-step synthetic sequence ranging from the elaboration of the existing purine/pyrimidine nucleobase through to more extensive preparation of analogues via N-glycosylation. Many of these synthetic steps to prepare 2'-deoxyribonucleosides by chemical synthesis require a series of protection/deprotection sequences, and in the context of N-glycosylation, produce regioisomeric and anomeric mixtures that can be challenging to purify.