(3R,5R,6R)-benzyl 6-DL-α-benzyloxycarbonylaminophenylacetamido-cyclopropanespiro-2-bisnorpenicillanate

{1-[(2R,3R)-3-(2-Benzyloxycarbonylamino-2-phenyl-acetylamino)-4-oxo-azetidin-2-ylsulfanyl]-cyclopropyl}-bromo-acetic acid benzyl ester

(3R,4R)-3-D-α-benzyloxycarbonylaminophenylacetamido-4-mercaptoazetidin-2-one

(1R,5R)-3-D-<(1-benzyloxycarbonylamino-1-phenyl)methyl>-6-<(2-methyl-1-benzyloxycarbonyl)prop-1-enyl>-4-thia-2,6-diazabicyclo<3.2.0>hept-2-en-7-one