110008-56-5 5-Thia-1-azabicyclo(4.2.0)oct-2-en-7-((3-chloroizoxazol-5-yl)acetamido)-3-(((1-methyl)-1H-tetrazol-5-yl)thiomethyl)-8-oxo-2-carboxylic acid 5-Thia-1-azabicyclo(4.2.0)oct-2-ene-2-carboxylic acid, 7-(((3-chloro-5-isoxazolyl)acetyl)amino)-3-(((1-methyl-1H-tetrazol-5-yl)thio)methyl)-8-oxo-, monosodium salt, (6R-trans)- BK 218 BK-218