5-Thia-1-azabicyclo(4.2.0)oct-2-one-2-carboxylic acid, 3-(((5-methyl-1,3,4-thiadiazol-2-yl)thio)methyl)-8-oxo-7-((1H-tetrazol-1-ylacetyl)amino)-, methyl ester, (6R-trans)- 79239-19-3 Cefazolin delta-2-methyl ester Methyl 3-(((5-methyl-1,3,4-thiadiazol-2-yl)thio)methyl)-8-oxo-7-((1H-tetrazol-1-ylacetyl)amino)-5-thia-1-azabicyclo(4.2.0)oct-2-one-2-carboxylate (6R-trans)- Ro 19-5248A Ro-19-5248A