Chemo-enzymatic synthesis of glycopolymers and sequential glycopeptides bearing lactosamine and sialyl Lewisx unit pendant chains

A variety of glycoconjugates bearing either N-acetyllactosamine or sialyl Lewis(x) units have been synthesised in a chemo-enzymatic way. This includes the synthesis of glycopolymer copolymerised with acrylamide and whose glucosamine unit was substituted with different kinds of side-chain. Glycopeptides with different spacer-arm glucosamine units have also been prepared and polymerised. The sugar chain was then elongated using glycosyl transferases to afford the novel sequential glycopeptides. In these cases, the polymeric sugar cluster effect led to enzymatic glycosylation with high efficiency. Nevertheless, some differences have been noticed depending on the reaction conditions used for each substrate.