Stereoselective 1,3-dipolar cycloadditions of exo-glycals 1 to nitrones 2,5 and 8 were investigated under the catalysis of Lewis acid or in a refluxing benzene or toluene solution,and afforded the corresponding cycloadducts of ketosyl spiro-isoxazolidines.The reductive cleavage of the N-O bond in the isoxazolidine ring and debenzylation by the catalytic hydrogenation [Pd(OH)2/C] were approached using the glucose-type cycloadducts 6b and 6e to alkyl-C-glycoside derivatives 12,providing a new access to a novel alkyl-C-glycoside containing an amino group on the side alkyl chain.