A mixture of N-[2-methoxy-4-(1-methyl-3,6-dihydro-2H-pyridin-4-yl)-5-nitrophenyl]-5-methyl-4-pyrazolo[1,5-a]pyridin-3-ylpyrimidin-2-amine (Intermediate 2, 279 mg, 0.59 mmol), iron (198 mg, 3.55 mmol) and NH4Cl (22.16 mg, 0.41 mmol) in ethanol (10.5 mL) and water (3.50 mL) was heated at reflux for 0.75 h. Further NH4Cl (22.16 mg, 0.41 mmol) and iron (198 mg, 3.55 mmol) were then added and the mixture was heated at reflux for a further 1.5 h. The mixture was then cooled, filtered, and the filtrate was concentrated in vacuo. Purification by FCC, eluting with 2-10% 7N methanolic ammonia in CH2Cl2 gave the title compound (150 mg, 57%) as a beige crystalline solid after trituration with THF and washing the resulting solid with diethyl ether; 1H NMR: 2.30 (3H, s), 2.40 (5H, m), 2.59 (2H, t), 3.01 (2H, d), 3.73 (3H, s), 4.27 (2H, s), 5.71 (1H, s), 6.63 (1H, s), 7.10 (1H, m), 7.35-7.49 (2H, m), 7.83 (1H, s), 8.27 (1H, s), 8.50-8.63 (2H, m), 8.81 (1H, d); m/z: ES+ MH+ 442.
