2-(2,4-Dichloro-benzoyl)-4-[1-(4-methoxy-phenyl)-meth-(E)-ylidene]-5-methyl-2,4-dihydro-pyrazol-3-one 、
氰乙酸乙酯 在
ammonium acetate 作用下,
以64%的产率得到1-(2,4-dichlorobenzoyl)-4-(4-methoxyphenyl)-3-methyl-6-oxo-5,7-dihydro-4H-pyrazolo[3,4-b]pyridine-5-carbonitrile