tert-Butyl 4-benzyloxy-3-tert-butoxy-2,5-dihydro-2-oxo-1H-pyrrole-1-carboxylate

(2S,3S,4S,5R,6R)-3,4,5-triacetoxy-6-bromo-tetrahydropyran-2-carboxylic acid benzyl ester

dibenzyl 2-<2,2-bis(methylthio)ethyl>-α-hydroxy-4-oxo-1-azetidinemalonate