(2S-(2 alpha,5 alpha,6 beta(S*)))-6-((aminophenylacetyl)amino)-3,3-dimethyl-7-oxo-4-thia-1-azabicyclo(3.2.0)heptane-2-carboxylic acid, (2,2-dimethyl-1-oxopropoxy)methyl ester, mono(4-((dipropylamino)sulfonyl)benzoate)