3,3'-Dimethyl-1,1'-diphenyl-4,4'-bi-5-pyrazolon 1,2-Dihydro-5-methyl-2-phenyl-3H-pyrazol-3-on Benzoldiazoniumchlorid 3-Methyl-1-phenyl-5-pyrazolon Phenylhydrazin Anilin 5-Oxo-1-phenyl-2-pyrazolin-3-carbonsure Ethyl-3-acetoxy-2-butenoat 4-Methylen-2-oxetanon