(3aR,3bS,6aR,7R,7aR)-7-benzoxy-2,2-dimethyl<1,3>dioxolo<4,5-a>cyclopent<4,5-d>oxazolidin-5-one

(3aR,3bR,6aS,7R,7aS)-7-benzoxy<1,3,2>dioxathiolo<4,5-a>cyclopent<4,5-d>oxazolidin-2,2,5-trione

(1S,2S,3R,4R,5R)-2-O-benzyl-5-((tert-butoxycarbonyl)amino)-3,4-O-isopropylidenecyclopentane-1,2,3,4-tetrol