Effective protection of the N-sulfate of glucosamine derivatives with the 2,2,2-trichloroethyl group

Abstract The 2,2,2-trichloroethyl (TCE) group was utilized as the first protecting group for N -sulfates (chlorosulfuric acid TCE ester, Et 3 N, DMAP, DMF). Glycosylation with 3,4,6-tri- O -acetyl- N -trichloroethylsulfuryl-α- d -glucosaminosyl trichloroacetimidate provided the corresponding β-glucosaminosides stereoselectively and in excellent yields. The TCE protection stayed stable under a variety of conditions for the manipulation of other protecting groups, and was readily removable with zinc in the presence of ammonium chloride in methanol.