4-Thia-1-azabicyclo(3.2.0)heptane-2-carboxylic acid, 6-(((((4-ethyl-2,3-dioxo-1-piperazinyl)carbonyl)amino)phenylacetyl)amino)-3,3-dimethyl-7-oxo-, (2S-(2alpha,5alpha,6beta(S*)))-
(2S,5R,6R)-6-{[(2R)-2-{[(4-ethyl-2,3-dioxopiperazin-1-yl)carbonyl]amino}-2-phenylacetyl]amino}-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0]heptane-2-carboxylic acid