反应详情

To N-(2-ethylcarbamoyl-ethoxy)-acetimidic acid ethyl ester (180 mg, 0.890 mmol) obtained in Step A was added 2 M hydrochloric acid (2 ml), and the mixture was stirred at room temperature for 30 minutes. The reaction mixture was concentrated to give a crude product of 3-aminooxy-N-ethyl-propionamide hydrochloride as a residue. To this residue, a mixed solvent of tetrahydrofuran/methanol (3:1, 20 ml) and 3,4-difluoro-2-(2-fluoro-4-iodophenylamino-5-formyl-N-(2-hydroxy-ethoxy)-benzamide (500 mg, 1.078 mmol) obtained in Step F of Example 1 were added, and the mixture was stirred for 1 hour. The reaction mixture was poured into purified water, and the resultant mixture was extracted with ethyl acetate. The combined organic layers were dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography to give (E)-5-[(2-ethylcarbamoyl-ethoxyimino)-methyl]-3,4-difluoro-2-(2-fluoro-4-iodo-phenylamino)-N-(2-hydroxy-ethoxy)-benzamide (200 mg, 31% yield).

1. concentrationThe reaction mixture was concentrated