The synthesis of multivalent neoglycoconjugates by 1,3-dipolar cycloaddition of nitrile oxides and alkynes is reported. The nitrile oxides are generated in situ in the presence of alkynyl derivatives allowing the access to homo and hetero multivalent systems containing O- and C-linked glycosides and isoxazole bridges. The concanavalin A binding affinities of some of these neoglyconjugates bearing mannose residues were evaluated by enzyme-linked lectin essay (ELLA). (c) 2005 Elsevier Ltd. All rights reserved.