Regioselective opening of unsymmetrical cyclic anhydrides: Synthesis of N-glycosylated isoasparagine and isoglutamine conjugates

Article abstract of DOI:10.1039/c4ra01234h

N-Glycopeptide mimetic with N-glycosylated isoasparagine and isoglutamine conjugates were synthesized by regioselective opening of unsymmetrical cyclic anhydride derivatives of l-aspartic acid and l-glutamic acid, using per-O-acetylated β-d-glycopyranosyl amine. The α-chloro derivative gave a mixture of asparagine and isoasparagine linked glycoconjugates, whereas the trifluoroacetamide derivatives gave predominantly the isoasparagine and isoglutamine linked glycoconjugates as the product. The X-ray crystal structure of the α-chloro isoasparagine linked glycoconjugate showed unique pattern of hydrogen bonding. This journal is the Partner Organisations 2014.