Synthesis and Immunological Screening of β-Linked Mono- and Divalent Mannosides

Three different β-linked divalent mannosides, along with their corresponding monovalent counterparts, have been designed and chemically synthesized by coupling the corresponding propargyl (propargyl alcohol in the case of the monovalent compounds) and 2-azidoethyl glycosides by using an efficient click chemistry protocol. Crich's β-mannosylation methodology was applied to the construction of the β-mannosidic linkages. All the glycosylation reactions gave moderate-to-good yields with high selectivities. A competitive inhibition enzyme-linked immunosorbent assay (ELISA) was performed to determine the inhibition, by the synthesized mannosides, of specific human IgG binding to low-molecular-weight Candida albicans mannan; moderate inhibition capacity was observed for some of the compounds.