Dendritic side chains have been used to modify the binding environment in anthracene-based synthetic carbohydrate receptors. Control of length, charge, and branching enabled the positioning of side-chain carboxylate groups in such a way that they assisted in binding substrates rather than blocking the cavity. Conformational degeneracy in the dendrimers resulted in effective preorganization despite the flexibility of the system. Strong binding was observed to glucosammonium ions in water, with Ka values up to 7000 m−1. Affinities for uncharged substrates (glucose and N-acetylglucosamine) were also enhanced, despite competition from solvent and the absence of electrostatic interactions.

Biomimetic carbohydrate receptors (“synthetic lectins”) have potential as agents for biological research and medicine. However, although effective strategies are available for “all‐equatorial” carbohydrates (glucose, etc.), the recognition of other types of saccharide under natural (aqueous) conditions is less well developed. Herein we report a new approach based on a pyrene platform with polar arches extending from aryl substituents. The receptors are compatible with axially substituted carbohydrates, and also feature two identical binding sites, thus mimicking the multivalency observed for natural lectins. A variant with negative charges forms 1:2 host/guest complexes with aminosugars, with K 1>3000 m −1 for axially substituted mannosamine, whereas a positively charged version binds the important α‐sialyl unit with K 1≈1300 m −1.

A monocyclic "temple" synthetic lectin, with extended electron-rich aromatic surfaces, shows enhanced affinities for carbohydrates in water. The methoxy substituents favour binding to α-linked maltodextrins, against the all-equatorial substrates normally favoured by this family of receptors.

Dendritic side chains have been used to modify the binding environment in anthracene-based synthetic carbohydrate receptors. Control of length, charge, and branching enabled the positioning of side-chain carboxylate groups in such a way that they assisted in binding substrates rather than blocking the cavity. Conformational degeneracy in the dendrimers resulted in effective preorganization despite the flexibility of the system. Strong binding was observed to glucosammonium ions in water, with K a values up to 7000 m À1 . Affinities for uncharged substrates (glucose and N-acetylglucosamine) were also enhanced, despite competition from solvent and the absence of electrostatic interactions.

Biomimetic carbohydrate receptors ("synthetic lectins") have potential as agents for biological researcha nd medicine.H owever,a lthough effective strategies are available for "all-equatorial" carbohydrates (glucose,e tc.), the recognition of other types of saccharide under natural (aqueous) conditions is less well developed. Herein we report an ew approach based on ap yrene platform with polar arches extending from aryl substituents.The receptors are compatible with axially substituted carbohydrates,a nd also feature two identical binding sites,t hus mimicking the multivalency observed for natural lectins.Avariant with negative charges forms 1:2h ost/guest complexes with aminosugars,w ith K 1 > 3000 m À1 for axially substituted mannosamine,w hereas ap ositively charged version binds the important a-sialyl unit with K 1 % 1300 m À1 .