反应详情

A mixture of ethyl 3-[N′-(2-bromophenyl)ureido]-2-methoxy-6-pyridylacetate (2.90 g, 7.10 mmol), 0.25 N NaOH (56.8 ml, 14.2 mmol), and THF (50 ml) was stirred for 5 h. The mixture was neutralized with 1 N HCl and the resulting precipitate was collected by filtration. The residue was recrystallized from CHCl3-MeOH-hexane to give 3-[N′-(2-bromophenyl)ureido]-2-methoxy-6-pyridylacetic acid (2.40 g, 89%) as a colorless crystalline powder. mp 195–197° C.; 1H-NMR (DMSO-d6) δ 3.59 (s, 2 H), 3.95 (s, 3 H), 6.88 (d, J=8.1 Hz, 1 H), 6.97–7.01 (m, 1 H), 7.33 (t, J=7.3 Hz, 1H), 7.61 (d, J=8.1 Hz, 1 H), 7.95–7.97 (m, 1 H), 8.29 (d, J=8.1 Hz, 1H), 8.81 (s, 1 H), 9.10 (s, 1 H), 12.35 (br s, 1 H); Anal. Calcd for C15H14BrN3O4: C, 47.39; H, 3.71; N, 11.05. Found: C, 47.27; H, 3.59; N, 10.86.

1. filtrationthe resulting precipitate was collected by filtration
2. customThe residue was recrystallized from CHCl3-MeOH-hexane