(2S,4R)-N-t-butoxycarbonyl-4-t-butyldimethylsilyloxy-2-[(E)-3-hydroxy-1-propenyl]pyrrolidine

(2S,4S)-N-allyloxycarbonyl-2-[(E)-3-allyloxycarbonylamino-1-propenyl]-N-allyloxycarbonyl-4-mercaptopyrrolidine

allyl (1R,5R,6S)-2-(diphenoxyphosphoryloxy)-6-[(R)-1-hydroxyethyl]-1-methylcarbapen-2-em-3-carboxylate

(2S,4R)-2-[(E)-3-allyloxycarbonylamino-1-propenyl]-N-allyloxycarbonyl-4-hydroxypyrrolidine

(2S,4R)-4-(tert-Butyl-dimethyl-silanyloxy)-2-((E)-3-methanesulfonyloxy-propenyl)-pyrrolidine-1-carboxylic acid tert-butyl ester