(4S,5R,6R)-4-azido-5-(2-oxo-pyrrolidin-1-yl)-6-(1R,2R,3-trihydroxy-propyl)-5,6-dihydro-4H-pyran-2-carboxylic acid methyl ester

(4S,5R,6R)-4-azido-5-propionylamino-6-(1R,2R,3-trihydroxypropyl)-5,6-dihydro-4H-pyran-2-carboxlic acid methyl ester

(4S,5R,6R)-4-amino-5-tert-butoxycarbonyl-amino-6-(1R,2R,3-trihydroxy-propyl)-5,6-dihydro-4H-pyran-2-carboxylic acid

(4S,5R,6R)-4-azido-5-tert-butoxycarbonyl-amino-6-(1R,2R,3-trihydroxy-propyl)-5,6-dihydro-4H-pyran-2-carboxylic acid

(4S,5R,6R)-4-azido-5-(4-chloro-butyrylamino)-6-(1S,2R,3-triacetoxy-propyl)-5,6-dihydro-4-H-pyran-2-carboxylic acid methyl ester