Abstract
The industrial development of carbohydrate-based drugs is greatly thwarted by the
typical challenges inherent in oligosaccharide synthesis. The practical advantages
of continuous-flow synthesis in microreactors (high reproducibility, easy scalability,
and fast reaction optimization) may offer an effective support to make carbohydrates
more attractive targets for drug-discovery processes. Here we report a systematic
exploration of the glycosylation reaction carried out under microfluidic conditions.
Trichloroacetimidates and thioglycosides have been investigated as glycosyl donors,
using both primary and secondary acceptors. Each microfluidic glycosylation has been
compared with the corresponding batch reaction, in order to highlight advantages and
drawbacks of microreactors technology. As a significant example of multistep continuous-flow
synthesis, we also describe the preparation of a trisaccharide by means of two consecutive
glycosylations performed in interconnected microreactors.
Keywords
carbohydrates - glycosylation - flow chemistry - natural products - oligosaccharides
- glycosides