The preparation of 2′-modified nucleosides often requires multi-step synthesis, with extensive protection/deprotection sequences or generates complex mixtures of regioisomers, making the synthesis of these molecules challenging. We considered a biocatalytic route to access 2′-modified nucleosides since enzymes are often able to carry out complex transformations in an atom efficient manner, under relatively mild conditions, and without the use of protecting groups. Moreover, since different biocatalysts often function under similar temperature and pH in aqueous solution, they can be combined into multienzyme cascades allowing for two or more reactions to be carried out in one pot without the need to isolate intermediates. This approach leads to a reduction in waste from intermediate/product isolation and also allows reactions to be coupled together, thereby overcoming potential thermodynamic barriers of individual reactions. These advantages have resulted in biocatalysis becoming increasingly deployed in the synthesis of active pharmaceutical ingredients (APIs). Recent reports have shown that enzymes from the nucleoside salvage pathway (Figure ) provide a useful platform for the generation of functionalized nucleosides. In the retrosynthetic direction, this pathway is responsible for the degradation of 2′-deoxynucleosides. Starting with a nucleoside phosphorylase (NP) the nucleobase is removed resulting in the generation of a C-1 phosphate sugar (Figure ). In the following step phosphopentomutase (PPM) catalyses transfer of the phosphate group from the 1' position to the 5' position, and finally deoxyribose-5-phosphate aldolase (DERA) breaks down the sugar into acetaldehyde and D-glyceraldehyde-3-phosphate via a retroaldol reaction. As all three enzymes catalyze reversible reactions they can be combined in the synthetic direction to generate nucleosides. An excellent example of this approach is the synthesis of the antiviral nucleoside analogue islatravir (Figure ) . There are additional examples of enzymes on this pathway being used to generate nucleoside analogues such as dideoxyinosine 9 and molnupiravir . Furthermore, there are also examples of other biocatalysts being employed in the synthesis of nucleosides, nucleotide analogues and oligonucleotides . Clearly to exploit this pathway for the synthesis of 2′ modified nucleosides, all enzymes in the pathway would need to possess sufficient promiscuity to tolerate a wide range of 2′-modifications. The initial challenge posed by this synthetic cascade is the limited substrate scope of DERA. While PPM and PNP enzymes have been shown to tolerate a small number of 2′-modifications , thus far the approach has been limited to 2′-deoxy nucleosides when starting from DERA, with acetaldehyde as the donor. Engineering DERA would allow the synthesis of 2-modified Dribose-5-phosphate analogues starting from D-glyceraldehyde-3-phosphate and an aldehyde donor. The products could then be further modified with the remaining enzymes in the pathway to generate 2′-functionalized nucleosides (Figure ).