35 mg (0.08 mmol) of 1-{3-[4-(2-aminopyridin-4-yl)-1H-pyrazol-3-yl]phenyl}-3-[4-(trifluoromethyl)-phenyl]urea were dissolved in 2 ml of dry tetrahydrofuran and 27 μl (0.16 mmol) of N,N-diisopropylethylamine and 14 μl of propionyl chloride (0.16 mmol) were added consecutively. The mixture was stirred overnight at room temperature, then poured into aqueous sodium hydrogenocarbonate, extracted with dichloromethane, dried over sodium sulphate ed evaporated. Without any further purification the crude was redissolved with 10 mL of methanol and 5 mL of triethylamine were added. After 7 hours at room temperature the solvent was removed in vacuo, the residue partitioned between dichloromethane and water, dried over sodium sulphate and evaporated. After trituration with diethylether, 30 mg (77%) of the title compound were collected by filtration.
