To a solution of 2-(3-chloropropyl)-4,6-bis(4-fluorophenyl)-5-(4-pyridyl)pyrazolo[3,4-b]pyridine (0.07 g, 0.1 mmol, obtained in example 16) in acetonitrile (0.3 mL), methylamine (1.8 mL of a 33% solution in EtOH, 14.6 mmol) was added under argon atmosphere. This was heated to 60° C. for 3 days, adding methylamine (0.9 mL and 3.6 mL of a 33% solution in EtOH) after 24 and 48 h respectively. The organic phase was dried over Na2SO4 and concentrated to dryness. The crude product obtained was purified by silica gel EtOAc-MeOH mixtures of using increasing polarity as eluent, to afford 24 mg of the title compound in solid form (yield: 29%).
