117929-10-9 5-Thia-1-azabicyclo(4.2.0)oct-3-ene-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-(6alpha,7beta))- Cefazolin delta-3-methyl ester Ro 19-5248 Ro-19-5248