(6R,7R)-7-amino-3-(5-methyl-1,3,4-thiadiazol-2-ylthiomethyl)-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid
2-(tert-butoxycarbonylamino)-2-phenylacetic acid
3-Bromophthalide
(6R)-7t-((R)-2-tert-butoxycarbonylamino-2-phenyl-acetylamino)-3-(5-methyl-[1,3,4]thiadiazol-2-ylsulfanylmethyl)-8-oxo-(6rH)-5-thia-1-aza-bicyclo[4.2.0]oct-2-ene-2-carboxylic acid