Multivalent presentation of carbohydrates by 314-helical peptide templates: synthesis, conformational analysis using CD spectroscopy and saccharide recognition

Abstract

A well defined 3₁₄-helical tetravalent β-galactopeptide site-specific functionalised template (SSFT) 1 was prepared containing D-galactose units, with free anomeric carbons as the aldehyde tags, and was explored via ligation with different aminoxy sugars (α-/β-D-glucose, α/β-D-galactose, α-D-mannose and β-D-lactose) to get 3₁₄-helical carbohydrate-functionalised multivalent glycoconjugates 2–7. Preliminary recognition studies of tetramannosyl glycoconjugate 4 with a specific lectin (concanavalin A) using fluorescence anisotropy showed an increase in binding affinity and the multivalency effect was found to be increased by 6.5 times per glycan.