| Abstract
| - The inclusion behavior and concanavalin A binding properties of hepta-antennated and newlysynthesized tetradeca-antennated C-6-branched mannopyranosyl and glucopyrannosyl cyclomaltoheptaose (β-cyclodextrin) derivatives have been evaluated by isothermal titration microcalorimetryand enzyme-linked lectin assay (ELLA), respectively. The synthesis of three first-order dendrimersbased on a β-cyclodextrin core containing 14 1-thio-β-d-glucose, 1-thio-β-mannose, and 1-thio-β-rhamnose residues was performed following a convergent approach and involving (1) preparationof a thiolated bis-branched glycoside building block and (2) attachment of the building block ontoheptakis(6-deoxy-6-iodo)-β-cyclodextrin. Calorimetric titrations performed at 25 °C in bufferedaqueous solution (pH 7.4) gave the affinity constants and the thermodynamic parameters for theinclusion complex formation of these β-cyclodextrin derivatives with guests sodium 8-anilino-1-naphthalensulfonate (ANS) and 2-naphthalenesulfonate. The host capability of the persubstitutedβ-cyclodextrins decreased with respect to the native β-CD when sodium 2-naphthalenesulfonatewas used as a guest and improved when ANS was used as a guest molecule. Heptavalentmannoclusters based on β-CD cores enhance the lectin binding affinity due to the cluster effect;however, the increase of the valency from 7 to 14 ligands did not contribute to the improvement ofthe concanavalin A binding affinity. In addition, the synthesized hyperbranched mannoCDs lostcompletely the capability as a host molecules.
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