1-Methyl-4-nitro-1H-pyrazole (1.62 g, 12.7 mmol) was used as the raw material, which was dissolved in methanol (250 mL) and hydrogenated on an H-Cube reactor at 60 bar hydrogen pressure and 70 °C to obtain 1-methyl-1H-pyrazol-4-amine (1.23 g, 99% yield). Subsequently, 1-methyl-1H-pyrazol-4-amine (700 mg, 7.0 mmol), 3-amino-6-bromopyridinecarboxylic acid (1.86 g, 8.5 mmol), PyBop (4.12 g, 8.0 mmol), dichloromethane (30 mL), and diisopropylethylamine (3.8 mL) were added to a 100 mL round-bottomed flask and the reaction mixture was stirred at room temperature for 24 h. The reaction progress was monitored by LCMS. Upon completion of the reaction, the solvent was removed by distillation and the crude product was purified by fast chromatography (eluent: heptane/ethyl acetate). A portion of the product was further purified by reversed-phase HPLC to afford the target compound 317.The product characterization data were as follows:1H NMR (400 MHz, DMSO) δ 10.25 (s, 1H), 8.03 (s, 1H), 7.70 (s, 1H), 7.43 (d, J = 8.7 Hz, 1H), 7.19 (d, J = 8.7 Hz, 1H), 7.02 (br, 2H), 3.81 (s, 3H); MS (ESI) m/z: 296.0/298.0 [M + H]+.
