RESUMO
Glycosylation significantly alters the biological and physicochemical properties of small molecules. ß-Lactam alcohols comprise eligible substrates for such a transformation based on their distinct relevance in the chemical and medicinal community. In this framework, the unprecedented enzymatic glycosylation of the rigid and highly strained four-membered ß-lactam azaheterocycle was studied. For this purpose, cis-3-hydroxy-ß-lactams were efficiently prepared in three steps by means of a classical organic synthesis approach, while a biocatalytic step was implemented for the selective formation of the corresponding 3-O-α- and -ß-glucosides, hence overcoming the complexities typically encountered in synthetic glycochemistry and contributing to the increasing demand for sustainable processes in the framework of green chemistry. Two carbohydrate-active enzymes were selected based on their broad acceptor specificity and subsequently applied for the α- or ß-selective formation of ß-lactam-sugar adducts, using sucrose as a glucosyl donor.
