To a suspension of the compound prepared in Example 9(54) (120 mg) and (1-methoxyisopropyl)oxyamine (31 mg) in dimethylformamide (1.6 ml) was added diisopropylethylamine (68 μl), 1-ethyl-3-[3-(dimethylamino)propyl]carbodiimide.hydrochloride (56 mg) and 1-hydroxybenztriazole (40 mg). The reaction mixture was stirred for 1 hour at room temperature. The reaction mixture was added 1N hydrochloric acid (2 ml) and stirred for 15 minutes at room temperature. The reaction mixture was diluted with water and extracted with ethyl acetate. The extract was washed with water, saturated aqueous solution of sodium bicarbonate and saturated aqueous solution of sodium chloride and the obtained residue was dried over anhydrous sodium sulfate and concentrated. To a solution of the obtained residue in methanol was added 4N hydrogen chloride/ethyl acetate solution and concentrated. The obtained residue was washed with ethyl acetate to give the title compound (116 mg) having the following physical data.
