To a solution of 0.07 g (0.16 mMol) 2-methoxy-N-(4-methoxy-7-piperidin-4-yl-benzothiazol-2-yl)-isonicotinamide 1:2 hydrochloride in 4 ml THF were added 0.049 ml triethyl amine. At 0° C. 0.018 ml (0.11 mMol) acetic anhydride was added dropwise and stirred for 1 h. Then a mixture of 5 ml sat. aqueous sodium bicarbonate and 10 ml water were added. This was extracted three times with 15 ml ethyl acetate, the combined organic phases were dried over sodium sulfate and evaporated to dryness in vacuo. One obtained 0.036 g (51%) N-[7-(1-acetyl-piperidin-4-yl)-4-methoxy-benzothiazol-2-yl]-2-methoxy-isonicotinamide as a white solid. F.p.: 242-244° C.
