The molecule is a penicilloate anion that is the conjugate base of benzylpenicilloic acid arising from zwitterion formation and deprotonation of the remaining carboxy group. It is a conjugate base of a benzylpenicilloic acid.
(2R,4S)-2-[(R)-carboxylato-[(2-phenylacetyl)amino]methyl]-5,5-dimethyl-1,3-thiazolidin-3-ium-4-carboxylate