(5R,?6S)?-6-?[(1R)?-?1-?Hydroxyethyl]?-?3-?[[(3S)?-?1-?[[(4-?nitrophenyl)?methoxy]?carbonyl]?-?3-?pyrrolidinyl]?thio]?-?7-?oxo-1-?azabicyclo[3.2.0]?hept-?2-?ene-?2-?carboxylic acid (4-?nitrophenyl)?methyl Ester is an intermediate in synthesizing Panipenem (P180000), a broad spectrum carbapenem antibacterial and antimicrobial agent working against Gram-negative and Gram-positive organisms.