A mixture of 3-(2,5-dichloropyrimidin-4-yl)pyrazolo[1,5-a]pyridine (Intermediate 21, 1.4 g, 5.28 mmol), 4-fluoro-2-methoxy-5-nitroaniline (Intermediate 23, 1.032 g, 5.55 mmol) and p-toluenesulfonic acid monohydrate (1.105 g, 5.81 mmol) was heated at 125° C. in 2-pentanol (40 mL) for 18 h. The mixture was then cooled and a solid was collected by filtration. The solid was washed with CH3OH and diethyl ether, and was then dried on the filter to give the title compound (1.73 g, 79%) as a yellow powder; 1H NMR: 3.98 (3H, s), 7.16 (1H, td), 7.33-7.48 (2H, m), 8.49 (1H, d), 8.53 (1H, d), 8.66 (1H, d), 8.86 (1H, d), 8.90 (1H, s), 8.96 (1H, s).
