To a slurry of (5-L-butyl-isoxazol-3-yl)-(2-chloro-pyrimidin-4-yl)-amine (0.110 g, 0.435 mmol, Step A) in DMSO (0.110 mL) was added 2-methyl-4,5-dimethoxyaniline (0.073 g, 0.435 mmol). The mixture was heated in a sealed tube at 110° C. for 90 min until TLC indicated the disappearance of starting materials. The mixture was taken up in CH2Cl2 (5 mL) followed by the addition of NaHCO3 (aq., sat. 1 mL) and H2O (5 mL). Extraction with CH2Cl2 (5×5 mL), followed by drying with MgSO4 and filtration yielded a crude mixture that was concentrated under reduced pressure. Purification by chromatography (97:3 CH2Cl2:MeOH) on silica gel afforded the title compound as a purple solid. MS m/z=384.2. Calc'd for C20H25N5O3: 383.45.
