N-((6-(5-Methoxy-1-methyl-1H-indol-3-yl)-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[2,3-b]pyrazin-2-yl)methyl)acetamide (0.200 g, 0.417 mmol) in DMF (10 mL) was treated with ethylenediamine (0.90 mL, 13 mmol) and TBAF (1 M in THF, 1.7 mL, 1.7 mmol). The mixture was heated to about 85° C. for about 90 min then cooled and concentrated under reduced pressure. The material was stirred with water (20 mL) for about 16 h, Et2O (10 mL) was added, and stirring was continued for about 15 min. The slurry was filtered and the solid collected was dried. The filtrate was extracted with EtOAc (2×25 mL) then the combined organic solutions were dried over anhydrous MgSO4, filtered, and concentrated to give material, which was combined with the previously collected solid. The material was triturated with EtOAc (5 mL) and filtered to give a solid. The filtrate was purified by silica gel chromatography eluting with DCM/MeOH (9:1) to give an additional amount of product which was combined with the solid obtained from the EtOAc trituration to give N-((6-(5-methoxy-1-methyl-1H-indol-3-yl)-5H-pyrrolo[2,3-b]pyrazin-2-yl)methyl)acetamide (0.108 g, 74%): LC/MS (Table 2, Method a) Rt=1.91 min; MS m/z: 350.2 (M+H)—.
