2-(4-Fluorophenyl)acetyl isocyanate → 2-{[4-(Azetidin-1-yl)piperidin-1-yl]carbonylamino}-4-(4-{3-[2-(4-fluorophenyl)acetyl]ureido}phenoxy)pyridine

Participants

Reaction Steps

To a solution of 4-(4-aminophenoxy)-2-{[4-(azetidin-1-yl)piperidin-1-yl]carbonylamino}pyridine (67.8 mg) in tetrahydrofuran (2.5 ml) was added a solution of 2-(4-fluorophenyl)acetyl isocyanate in tetrahydrofuran (0.25 M, 2.2 ml) at room temperature, followed by stirring for 2 hours. A solution of 2-(4-fluorophenyl)acetyl isocyanate in tetrahydrofuran (0.25 M, 1.5 ml) was further added thereto at room temperature. After 6 hours, a solution of 2-(4-fluorophenyl)acetyl isocyanate in tetrahydrofuran (0.25 M, 1.85 ml) and diisopropylethylamine (0.322 ml) were added thereto at room temperature, followed by stirring for 2 days. The reaction mixture was partitioned between ethyl acetate and a saturated aqueous solution of sodium hydrogencarbonate. The organic layer was washed with brine and dried over anhydrous sodium sulfate. The solvent was evaporated to give a residue, which was then purified by silica gel column chromatography (Fuji Silysia NH, eluent; ethyl acetate, then ethyl acetate:methanol=97:3). Fractions containing the target compound were concentrated to give a residue, which was then suspended in ethyl acetate (1 ml). The solid was filtered off and dried under aeration to provide the titled compound (17.0 mg, 17%) as white powder.

Provenance & Evidence