Sodium (5R,6S)-1,1-dimethyl-6-<(R)-1-hydroxyethyl>-2-(1,3,4-thiadiazol-2-yl)thiomethylcarbapen-2-em-3-carboxylate

3-(S)-[1-(R)-(tert-butyldimethylsilyloxy)-ethyl]-4-(R)-((1S,3R)-3-butoxy-2-oxo-cyclohexyl)-azetidin-2-one

3-(S)-[1-(R)-(tert-butyldimethylsilyloxy)-ethyl]-4-(R)-((1R,3S)-3-butoxy-2-oxo-cyclohexyl)-azetidin-2-one

Acetic acid (2R,3R)-1-[((Z)-but-2-enyl)-dimethyl-silanyl]-3-[(R)-1-(tert-butyl-dimethyl-silanyloxy)-ethyl]-4-oxo-azetidin-2-yl ester

(5R,6S)-6-[(R)-1-(tert-Butyl-dimethyl-silanyloxy)-ethyl]-1-aza-bicyclo[3.2.0]hept-3-en-7-one