Sodium azide (260 mg, 4.0 mmol) and ammonium chloride (210 mg, 4.0 mmol) were suspended in a solution of quinoline-6-carboxylic acid cyanomethyl-amide described in Preparation Example E-1 (420 mg, 2.0 mmol) in N,N-dimethylformamide (15 mL), and the solution was stirred at 100° C. for 12 hours. Benzyl bromide (0.12 mL, 1.0 mmol) and potassium carbonate (400 mg, 3.0 mmol) were added to a solution having half the amount of the solution containing quinoline-6-carboxylic acid (2H-tetrazol-5-ylmethyl)amide obtained, which was then stirred for 20 minutes at 50° C. Water and ethyl acetate were added to the reaction solution, which was then partitioned, NH silica gel was added to the organic layer, and the solvent was evaporated in vacuo for adsorption, purification was carried out by NH silica gel column chromatography, and the title compound (20 mg, 0.058 mmol) was obtained as a white solid.
