5-Thia-1-azabicyclo(4.2.0)oct-2-ene-2-carboxylic acid, 7-((2-(((4-ethyl-2,3-dioxo-1-piperazinyl)carbonyl)amino)-3-hydroxy-1-oxobutyl)amino)-7-methoxy-3-(((1-methyl-1H-tetrazol-5-yl)thio)methyl)-8-oxo-, (6R-(6alpha,7alpha,7(2R*,3S*)))-