Aqueous 2 N LiOH (1.1 mL, 2.2 mmol) is added to a stirred solution of 2-{5-chloro-2-[3-(4-methylpiperazin-1-yl)-propylamino]-pyrimidin-4-yl}-benzo[b]thiophene-4-carboxylic acid methyl ester (280 mg, 0.610 mmol) in water (3 mL), MeOH (6 mL) and THF (12 mL). The mixture is heat at 70° C. for 2 hours. While at 70° C., 5 N HCl (1 mL) is added to the solution, then the solution is allowed to cool to room temperature. After concentration, the yellow solid is suspended in THF (20 mL), sonicated, filtered, and dried to give the title compound as a solid (320 mg, 94% yield).
