F[C:2]1[CH:7]=[CH:6][C:5]([C:8]2[O:9][C:10]3[CH:16]=[CH:15][CH:14]=[CH:13][C:11]=3[N:12]=2)=[CH:4][C:3]=1[N+:17]([O-])=O.[OH:20][CH2:21][CH2:22][NH2:23].C(N(CC)CC)C.[H][H]>C(#N)C.[C].[Pd].O>[OH:20][CH2:21][CH2:22][NH:23][C:2]1[CH:7]=[CH:6][C:5]([C:8]2[O:9][C:10]3[CH:16]=[CH:15][CH:14]=[CH:13][C:11]=3[N:12]=2)=[CH:4][C:3]=1[NH2:17]To a suspension of 2-(4-fluoro-3-nitrophenyl)benzoxazole (see Working Example 15-2) (0.50 g, 1.9 mmol) in acetonitrile (10 mL) was added 2-hydroxyethylamine (0.14 g, 2.1 mmol) and triethylamine (0.29 g, 2.4 mmol), and this was heated to reflux for 6 hours. After the reaction was complete, this was cooled to room temperature, water was added, and the precipitated crystals were filtered, washed with water and then dried. To a solution of the residue obtained in a solvent mixture of methanol/tetrahydrofuran=1:1 (50 mL) was added 10% palladium-carbon (50 mg). A hydrogen atmosphere was substituted in the flask, and this was stirred at room temperature for 3 hours. After the reaction was complete, this was filtered through Celite and the filtrate was concentrated. The residue obtained was purified by silica gel column chromatography to yield the title compound (0.36 g, 70% yield) as a pale yellow solid.
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