To a solution of 6-chloro-1-(1,1-dimethylethyl)-3-methyl-1H-pyrazolo[3,4-b]pyridine-4-carboxylic acid (320 mg, 1.195 mmol) in DMSO(7 mL) were added 3-(aminomethyl)-4,6-dimethyl-2(1H)-pyridinone (338 mg, 1.793 mmol), N-methylmorpholine (0.526 mL, 4.78 mmol), 1-hydroxy-7-azabenzotriazole (325 mg, 2.391 mmol) and EDC (458 mg, 2.391 mmol), and the reaction mixture was stirred overnight. The reaction mixture was quenched with water (20 mL) and stirred for 10 min. The precipitate was collected by filtration and further dried under high vacuum to give the product as a solid, 450 mg (94%). LCMS E-S (M+H)=402.1. 1H NMR (400 MHz, DMSO-d6) δ ppm 1.71 (s, 9 H), 2.12 (s, 3 H), 2.22 (s, 3 H), 2.37 (s, 3 H), 4.33 (d, J=4.80 Hz, 2 H), 5.88 (s, 1 H), 7.09-7.21 (m, 1 H), 8.77 (t, J=4.93 Hz, 1 H), 11.53 (s, 1 H).
