methyl 1-(carbamoylamino)-4-[(4-chlorophenyl)carbamoyl]-2,5-dimethylpyrrole-3-carboxylate

(2E)-N-(4-氯苯基)-2-(羟基亚胺)-3-氧代丁酰胺

2-(4-chlorophenyl)-5-methyl-1,2-oxazol-3-one

methyl 2-(4-chloroanilino)-2-oxoacetate