Synonyms: 5-Thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, 3-methyl-8-oxo-7-(2-phenoxyacetamido)-, diphenylmethyl ester (7CI,8CI);5-Thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid,3-methyl-8-oxo-7-[(phenoxyacetyl)amino]-, diphenylmethyl ester, (6R,7R)- (9CI);5-Thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid,3-methyl-8-oxo-7-[(phenoxyacetyl)amino]-, diphenylmethyl ester, (6R-trans)-