(1R,2S,3R,4S,6S)-tert-butyl 2,3-dihydroxy-5-oxo-6-(phenylsulfonyl)-7-azabicyclo[2.2.1]heptane-7-carboxylate

(1R,2S,3R,4S,5R,6S)-tert-butyl 2,3,5-trihydroxy-6-(phenylsulfonyl)-7-azabicyclo[2.2.1]heptane-7-carboxylate

tert-butyl (3aR,4R,5R,6R,7R,7aS)-5-hydroxy-2,2-dimethyl-6-(phenylsulfonyl)hexahydro-4,7-epiminobenzo[d][1,3]dioxole-8-carboxylate

tert-butyl ((3aR,4R,5R,6R,7R,7aS)-5,6,7-trihydroxy-2,2-dimethylhexahydrobenzo[d][1,3]dioxol-4-yl)carbamate