(3S,4R)-5-[N-(benzyloxycarbonyl)amino]-5-deoxypent-2-ulose

(6R,7R,7aR)-6,7-dihydroxy-tetrahydro-pyrrolo[1,2-c]oxazol-3-one

Benzoic acid (2S,3R,4S)-3,4-dihydroxy-5-oxo-pyrrolidin-2-ylmethyl ester