(5S,7R)-2,2,3-trimethyl-7-mesyloxy-4-oxo-1,3-diazabicyclo<3.3.0>octane

Methanesulfonic acid (3R,5S)-5-carbamoyl-pyrrolidin-3-yl ester

Thioacetic acid S-((6S,7aS)-3-cyclopropyl-3-methyl-1-oxo-hexahydro-pyrrolo[1,2-c]imidazol-6-yl) ester

Thioacetic acid S-((6S,7aS)-3,3-diethyl-1-oxo-hexahydro-pyrrolo[1,2-c]imidazol-6-yl) ester

(4R,5S,6S)-3-((6S,7aS)-3,3-Diethyl-1-oxo-hexahydro-pyrrolo[1,2-c]imidazol-6-ylsulfanyl)-6-((R)-1-hydroxy-ethyl)-4-methyl-7-oxo-1-aza-bicyclo[3.2.0]hept-2-ene-2-carboxylic acid