282732-07-4

1-Azabicyclo[3.2.0]hept-2-ene-2-carboxylic acid,6-[(1R)-1-hydroxyethyl]-4-methyl-7-oxo-3-[[(3R)-5-oxo-3-pyrrolidinyl]thio]-, 1-ethylpropyl ester, (4R,5S,6S)-