Finally, the combination of different biosynthetic enzymes in in vitro cascades also proved highly fruitful in the gramscale synthesis of different non-standard sugar nucleotides as demonstrated by Wen and coworkers. Starting from the feedstock chemical N-acetyl glucosamine, the application of efficient cofactor regeneration systems in the reduction, oxidation, amination and/or acetylation steps was crucial to drive the concurrent cascades toward target sugar nucleotide formation.