A mixture of 3-(2,5-dichloropyrimidin-4-yl)-1-methylindole (Intermediate 88, 1281 mg, 4.60 mmol), p-toluene sulphonic acid monohydrate (964 mg, 5.07 mmol) and 4-fluoro-2-s methoxy-5-nitroaniline (Intermediate 23, 900 mg, 4.84 mmol) in 2-pentanol (50 mL) was heated at 125° C. for 18 h. A precipitate formed from the solution upon cooling. The precipitate was collected by filtration, washed with CH3OH (10 mL) and diethyl ether (20 mL) and dried on the filter to give the title compound (1.42 g, 72%) as a tan solid, which was used without further purification; 1H NMR: 3.91 (3H, s), 3.96 (3H, s), 7.05 (1H, t), 7.23-7.3 (1H, m), 7.39 (1H, d), 7.53 (1H, d), 8.33 (1H, d), 8.47 (1H, s), 8.58 (1H, s), 8.65 (1H, d), 8.76 (1H, s); m/z: ES+ MH+ 428.10.
