To a solution of {4-[4-(1-methylpiperidin-4-yloxy)-9,10-dihydro-4H-3,10a-diaza-benzo[f]azulen-2-yl]-phenyl}-carbamic acid tert-butyl ester (example 49A) (45 mg, 0.092 mmole) in CH2Cl2 (0.3 mL) is added trifluoroacetic acid (90 μL). The reaction mixture is stirred at room temperature for 1 hour. Water is added and pH adjusted to 9-10 with 1N NaOH. The aqueous phase is extracted three times with CH2Cl2. The organic phase is dried over magnesium sulphate, filtered and the solvent is removed under reduced pressure. The residue is purified by silica gel chromatography using (CH2Cl2:MeOH:NH4OH) as eluent with a gradient from (98:2:0.2) to (95:5:0.5) to give 4-[4-(1-methylpiperidin-4-yloxy)-9,10-dihydro-4H-3,10a-diaza-benzo[f]azulen-2-yl]-phenylamine melting at 197° C.
