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

(4R,5S,6S)-3-[(3S,5S)-1-Allyloxycarbonyl-5-((E)-3-allyloxycarbonylamino-propenyl)-pyrrolidin-3-ylsulfanyl]-6-((R)-1-hydroxy-ethyl)-4-methyl-7-oxo-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid allyl ester

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