(4R,5S,6S)-6-((R)-1-Hydroxy-ethyl)-3-[(2R,3R,4R)-2-methoxycarbonyl-4-(toluene-4-sulfonyloxymethyl)-oxetan-3-ylsulfanyl]-4-methyl-7-oxo-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid 4-nitro-benzyl ester

4-nitrobenzyl (1R,5S,6S)-6-[(R)-1-hydroxyethyl]-1-methyl-2-[(2S,4S)-1-methyl-2-[3-(4-nitrobenzyloxycarbonylamino)azetidin-1-ylcarbonyl]pyrrolidin-4-ylthio]-1-carbapen-2-em-3-carboxylate

4-Nitrobenzyl (1R,5S.6S)-2-{(3S,5S)-5-[3(S)-(4-nitrobenzyloxycarbonyl)aminopyrrolidin-1-ylcarbonyl]-1-methylpyrrolidin-3-ylthio}-6-[1(R)-hydroxyethyl]-1-methyl-1-carbapen-2-em-3- carboxylate

4-nitrobenzyl (1R,5S,6S)-2-[(2S,4S)-2-[3-(4-nitrobenzyloxycarbonylamino)azetidin-1-ylcarbonyl]-1-(4-nitrobenzyloxycarbonyl)pyrrolidin-4-ylthio]-6-[(R)-1-hydroxyethyl]-1-methyl-1-carbapen-2-em-3-carboxylate

6-(1-hydroxy-ethyl)-4-methyl-3-(1-(4-nitro-benzyloxycarbonyl)-5-{3-[2-(4-nitro-benzyloxycarbonylamino)-acetylamino]-pyrrolidine-1-carbonyl}-pyrrolidin-3-ylsulfanyl)-7-oxo-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid 4-nitro-benzyl ester