Boronic Acid-Assisted Site-Selective Benzylation of Unprotected Saccharides

Site-selective benzylation of specific hydroxyl groups (OH) in unprotected saccharides is crucial for the synthesis of complex saccharide-based pharmaceuticals. However, it remains a significant challenge due to the minimal reactivity differences among multiple chemically similar OH groups. Herein, we present a site-switchable, one-step synthetic benzylation strategy through strategically tuning the structure of boronic acids. This general and practical strategy establishes a framework for the rapid assembly of structurally diverse saccharide derivatives.