Not available,(2RS,4S)-2-[[[(2R)-2- [[(4-ethyl-2,3-dioxopiperazin-1-yl)carbonyl]amino]-2-phenylacetyl]amino]methyl]-5,5-dimeth ylthiazolidine-4-carboxylic acid,"Monodecarboxy Piperacilloic Acid is an impurity of Piperacillin , a beta-lactam antibiotic.",Piperacillin Impurity