A mixture of 3-[4-amino-5-(2-benzyl-2H-indazol-6-yl)pyrrolo[2,1-f][1,2,4]triazin-7-yl]piperidin-3-ol (154 mg, 0.35 mmol), N,N-dimethylglycine (43 mg, 0.42 mmol), EDCl (74 mg, 0.39 mmol), HOBt (52 mg, 0.39 mmol), and N,N-diisopropylethylamine (183 μL, 1.05 mmol) in DMF (3.0 mL) was stirred at rt for 80 h. The crude mixture was purified by preparative HPLC using a gradient elution from 15% to 45% acetonitrile in water followed by filtration through an acidic resin, washing with MeOH. The product was eluted with 2M NH3 in MeOH and the filtrate was concentrated to provide 61 mg (33%) of the desired product. ES-MS m/z 525.52 [M+H]+, HPLC RT (min) 2.04.
