Synthesis and conjugation of a sulfated disaccharide involved in the aggregation process of the marine sponge Microciona prolifera

Abstract

The synthesis is reported of allyl (sodium 2-acetamido-2-deoxy-β- d-glucopyranosyl 3-sulfate)-(1→3)-α- l-fucopyranoside which represents an oligosaccharide fragment of the aggregation factor of the marine sponge Microciona prolifera. The title compound was obtained by coupling of 3- O-allyloxycarbonyl-2-deoxy-4,6- O-isopropylidene-2-phthalimido-β- d-glucopyranosyl trichloroacetimidate with allyl 2,4-di- O-benzoyl-α- l-fucopyranoside, followed by de-isopropylidenation, acetylation, de-allyloxycarbonylation, sulfation, de-acylation, and finally N-acetylation. The allyl glycoside was eventually converted into a 3-(2-aminoethylthio)propyl glycoside and then coupled to bovine serum albumin (BSA) using diethyl squarate as the bivalent linker, yielding 8 hapten molecules per molecule of BSA.