To a solution of 54 mg of 4-[(S)-3-aminopyrrolidin-1-yl]-N,N-dimethyl-benzenesulfonamide and 30 mg of 2-methoxyacetophenone in 1 ml of THF was added 85 mg of titanium isopropoxide, and the mixture was stirred at room temperature for 1 day. Further, 12 mg of sodium borohydride was added to the reaction mixture, and then, 0.3 ml of methanol was added to the mixture, and the mixture was stirred at room temperature for 4 hours. To the reaction mixture was added 0.5 ml of 28% aqueous ammonia solution, the mixture was stirred, and then, insoluble materials were removed and the solvent was evaporated. The residue was purified by LC/MS to obtain 61 mg of 4-[(S)-3-[1-(2-methoxyphenyl)ethylamino]pyrrolidin-1-yl]-N,N-dimethyl-benzenesulfonamide. The 4-[(S)-3-[1-(2-methoxyphenyl)ethylamino]pyrrolidin-1-yl]-N,N-dimethyl-benzenesulfonamide was dissolved by adding 1 ml of tert-butanol, 0.15 ml of 2M aqueous hydrochloric acid was added thereto, and after stirring the mixture, it was freeze-dried to obtain 4-[(S)-3-[1-(2-methoxyphenyl)ethylamino]-pyrrolidin-1-yl]-N,N-dimethyl-benzenesulfonamide dihydrochloride (the following Table Y, Example 13.001).
