[NH2:1][C:2]1[N:6]([C:7]2[CH:12]=[CH:11][CH:10]=[CH:9][C:8]=2[CH3:13])[N:5]=[CH:4][C:3]=1[C:14]([NH2:16])=[O:15].[Br:17][C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][C:19]=1[CH2:24][C:25](OC)=O.[O-]CC.[Na+].O>C(O)C.C(OCC)(=O)C>[Br:17][C:18]1[CH:23]=[CH:22][CH:21]=[CH:20][C:19]=1[CH2:24][C:25]1[NH:16][C:14](=[O:15])[C:3]2[CH:4]=[N:5][N:6]([C:7]3[CH:12]=[CH:11][CH:10]=[CH:9][C:8]=3[CH3:13])[C:2]=2[N:1]=12.0 g (9.25 mmol) of 5-amino-1-(2-methylphenyl)-1H-pyrazole-4-carboxamide (Example 25A) and 9.5 g (41.62 mmol) of methyl (2-bromophenyl)acetate are dissolved in 30 ml of absolute ethanol under argon, and 3.15 g (46.6 mmol) of sodium ethoxide are added. The reaction mixture is heated to a reflux overnight. Cooling to room temperature is followed by hydrolysis with 50 ml of water and subsequent extraction with ethyl acetate (2×50 ml). The combined organic phases are dried over sodium sulphate, and the solvent is distilled off under reduced pressure. The crude product is then purified by column chromatography (silica gel; mobile phase cyclohexane/ethyl acetate, gradient 10:1→1:1). 3.01 g (82% of theory) of the product are obtained.
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