[(3S,4R)-5-azido-2-[[tert-butyl(diphenyl)silyl]oxymethyl]-6-ethoxy-3-hydroxyoxan-4-yl] benzoate;(3S,4R)-5-azido-2-[[tert-butyl(diphenyl)silyl]oxymethyl]-6-ethoxy-3-methoxyoxan-4-ol;[(3S,4R)-5-azido-2-[[tert-butyl(diphenyl)silyl]oxymethyl]-6-ethoxy-3-methoxyoxan-4-yl] benzoate;[(3S,4R,6S)-5-azido-2-[[tert-butyl(diphenyl)silyl]oxymethyl]-3-hydroxy-6-methylsulfanyloxan-4-yl] benzoate;[(3S,4R)-5-azido-4,6-diethoxy-3-methoxyoxan-2-yl]methoxy-tert-butyl-diphenylsilane