5-Thia-1-azabicyclo(4.2.0)oct-2-enecarboxylic acid, 7-(((((6-(4-(((1-acetyl-4-hydroxy-2-pyrrolidinyl)carbonyl)amino)phenyl)-1,2-dihydro-2-oxo-3-pyridinyl)carbonyl)amino)phenylacetyl)amino)-3-((acetyloxy)methyl)-8-oxo-, monosodium salt, (6R-(6-alpha,7-beta(R*(2S*,4R*))))- 77004-29-6