To a solution of 2-cyclopropyl-N-(4,4-dimethyl-1-(methylsulfonyl)piperidin-3-yl)-5-((2-(trimethylsilyl)ethoxy)methyl)-5H-pyrrolo[2,3-b]pyrazine-7-carboxamide (143 mg, 0.27 mmol) in CH2Cl2 (5 mL) was added TFA (2.0 mL, 26.0 mmol). The yellow reaction mixture was stirred for 3 h then concentrated The residue was redissolved in CH2Cl2 (5 mL) and ethylenediamine (0.5 mL, 7.4 mmol) was added. The reaction mixture was stirred at for 1 h then concentrated. The residue was purified by SiO2 chromatography (50% to 100% EtOAc/hexanes to 5% MeOH/EtOAc) to isolate 66 mg (62%) of 2-cyclopropyl-5H-pyrrolo[2,3-b]pyrazine-7-carboxylic acid (1-methanesulfonyl-4,4-dimethyl-piperidin-3-yl)-amide as a white solid. MS: (M+H)+=392.
