Thio-sugars IV: Design and synthesis of S-linked fucoside analogs as a new class of α-L-fucosidase inhibitors

α-1-Thio- -fucose derivative 4 and 5 as new α-fucosidase inhibitors (KI = 4.6, and 5.9 μM) have been synthesized in three steps by base catalyzed coupling with bromonitromethane followed by reduction of the nitro group with sodium borohydride/cobalt chloride complex and acetylation.