Synthesis of C2-symmetric guanidino-sugars as potent inhibitors of glycosidases Original Research Article

A series of enantiomerically pure C2-Symmetric guanidino-sugars was synthesized from d-mannitol. The first method described involves direct opening of a bis-epoxide by guanidine, whereas the second one deals with a mercury-catalyzed transformation of a cyclic thiourea into a N,N′,N″-trisubstituted guanidine as a key step. The biological activity of these compounds towards several glycosidases has been evaluated. One of them was found to selectively inhibit α-l-fucosidase of bovin kidney (2.8 μM).