Synonyms: 5-Thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylicacid, 7-[(aminophenylacetyl)amino]-3-chloro-8-oxo-, monohydrate, [6R-[6a,7b(R*)]]-;5-Thia-1-azabicyclo[4.2.0]oct-2-ene-2-carboxylic acid,7-[[(2R)-aminophenylacetyl]amino]-3-chloro-8-oxo-, monohydrate, (6R,7R)- (9CI);Cephaclor monohydrate;Cefaclor;