Valeryl chloride → 3-(4-{2-[3-(2,4-difluorophenyl)-1-pentylureido]ethoxy}phenyl)-2-ethoxypropionic Acid

Participants

Reaction Steps

A solution of the compound obtained in Example 1, Step c (42 mg) in methylene chloride (2 ml) was added with pyridine (32 μl) and valeryl chloride (21.4 μl, Tokyo Kasei Kogyo) and stirred at room temperature for 4 hours. The reaction mixture was added with tetrafluorophthalic anhydride (22 mg) and further stirred for 2 hours. The reaction mixture was added with a polyamine resin (100 mg, prepared by the same method as described in Example 3), stirred for 1.5 hours and filtered, and the filtrate was concentrated. The resulting residue was dissolved in THF (1 ml), added with ethyl acetate (200 μl) and borane/dimethyl sulfide complex (36 μl, Tokyo Kasei Kogyo) and stirred at room temperature for 20 hours. The reaction mixture was added with ethanol (0.2 ml) and stirred at room temperature for 1 hour and at 50° C. for 1 hour. The reaction mixture was concentrated, and the resulting residue was dissolved in methylene chloride, washed with 1 N aqueous sodium hydroxide, dried and concentrated. Because a TLC analysis verified that the reaction was incomplete, a THF solution of the residue was prepared again and subjected to the reduction reaction and the post-treatments again. By using the resulting compound, the title compound (5.6 mg) was obtained in the same manner as that of Example 3 except that 2,4-difluorophenyl isocyanate (Aldrich) was used instead of the 2,4-dimethoxyphenyl isocyanate.

Provenance & Evidence