129 mg of (1S, 2R)-3-(3,4-dichlorophenyl)-1-methyl-2-(2-naphthoyloxy)propylamine hydrochloride and 120 μl of triethylamine were dissolved in 15 ml of methylene chloride, and 82 mg of 3-(tert-butyldimethylsilyloxy)glutaric anhydride was added thereto with stirring under cooling with ice. The mixture was stirred at room temperature for 3 hours. The reaction solution was extracted by an addition of 1N hydrochloric acid and methylene chloride. The organic layer was dried over anhydrous magnesium sulfate. The drying agent was separated by filtration, and the solvent was distilled off under reduced pressure. The residue was dissolved in a liquid mixture of 10 ml of tetrahydrofuran and 5 ml of 1N hydrochloric acid, and the solution was left to stand at room temperature overnight. The reaction solution was extracted by an addition of water and ethyl acetate. The organic layer was washed with a saturated sodium chloride aqueous solution and then dried over anhydrous magnesium sulfate. The drying agent is separated by filtration, and then the solvent was distilled off under reduced pressure. The residue was subjected to silica gel thin layer chromatography (Kieselgel™ 60F254, Art 5744, manufactured by Merck Co.; chloroform/methanol=6/1) to obtain 112 mg (yield: 71%) of the above-identified compound as white powder.
