(2S,4S)-2-(1-allyloxycarbonyl-4,5-dihydro-1H-imidazol-2-yl)-4-tritylthio-1-(allyloxycarbonyl)pyrrolidine

(4R,5S,6S)-3-((3S,5S)-1-Allyloxycarbonyl-5-{[(thiomorpholine-4-carbonyl)-amino]-methyl}-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

(2R,4S)-2-{2-[(Z)-Hydroxyimino]-2-[(piperazine-1-carbonyl)-amino]-ethyl}-4-tritylsulfanyl-pyrrolidine-1-carboxylic acid allyl ester

(2S,4S)-2-(1-Isopropyl-4,5-dihydro-1H-imidazol-2-yl)-4-tritylsulfanyl-pyrrolidine-1-carboxylic acid allyl ester

allyl (2S,4S)-2-((2-((N,N-dimethylsulfamoyl)amino)ethyl)carbamoyl)-4-(tritylthio)pyrrolidine-1-carboxylate