2-Deoxy-2-[(2,2-dimethoxycarbonylvinyl)amino]- ( 1) and 2-deoxy-2-[(2,2-diethoxycarbonylvinyl)amino]-α- d-glucopyranose ( 3), prepared in almost quantitative yields from the appropriate 3-alkoxy-2-alkoxycarbonylacrylic ester and 2-amino-2-deoxy- d-glucose hydrochloride, were used as N-protected derivatives in the preparation of glycosides by the Fischer procedure. Glycosidation of 1 with boiling methanolic hydrogen chloride afforded a mixture of methyl 2-deoxy-2-[(2,2-dimethoxycarbonylvinyl)amino]-α- ( 7α) and -β- d-glucopyranoside ( 7β), and minor amounts of methyl 2-deoxy-2-[(2,2-dimethoxycarbonylvinyl)amino]-α- d-glucofuranoside ( 18); 7α was easily isolated (55% yield). Using Amberlyst-15 (H +) resin as catalyst, the proportion of the furanoside 18 was higher and 21% could be isolated. Reaction of 3 with hot ethanolic hydrogen chloride afforded a good yield of ethyl 2-deoxy-2-[(2,2-diethoxycarbonylvinyl)amino]-α- d-glucopyranoside. On the other hand, attempted glycosidations of 2-deoxy-2-[(2,2-diacetylvinyl)amino]-α- d-glucopyranose under similar conditions were unsuccessful. The 2,2-diacylvinyl group could be removed selectively under non-acidic conditions using chlorine, ammonia, or Amberlite IRA-400 (HO −) resin.