A solution of the compound (150 mg, 0.344 mmol) obtained in Example 66, cyclopropylamine (119 μL, 1.72 mmol), N,N-dimethylaminopyridine (4 mg, 34 μmol), and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (198 mg, 1.03 mmol) in N,N-dimethylformamide (3.00 mL) was stirred at room temperature for 5 h. Saturated aqueous sodium hydrogencarbonate (100 mL) was added to the reaction mixture, the mixture was extracted with dichloromethane, and the organic layer was washed with water and dried with anhydrous sodium sulfate. Then the solvent was distilled off under reduced pressure. Diisopropyl ether was added to the residue, and the precipitate was collected by filtration and purified by silica gel column chromatography (ethyl acetate:methanol=1:4) to obtain the title compound (29 mg, 18%) as a white solid.
