To a solution of 4-(2-(1-(tert-Butoxycarbonylamino)propan-2-yloxy)-4-fluorophenylamino)-5-methylthieno[2,3-d]pyrimidine-6-carboxylic acid (80 mg) in DMF (1 ml), TBTU (54 mg) and triethylamine (60 μl) were added. The mixture was stirred at room temperature for 5 min then methylamine in THF (2M; 420 μl) was added and the reaction stirred at room temperature overnight. The mixture was diluted with methanol and purified directly by RP-chromatography (water with 0.2% trifluoroacetic acid/methanol 72-100%) to give the title compound.
