反应详情

温度

60 °C

To a mixture consisting of the solid comprising ethyl 2,4-dioxo-4-(2-phenoxypyrimidin-5-yl)butanoate (Step A, 1.00 mmol theory) in acetic acid (10 mL) was added hydrazine (0.40 mL, 410 mg, 13 mmol). The stirring mixture was heated to 60° C. for one hour and was subsequently cooled to room temperature and stirred overnight. The off-white solid which had precipitated was collected by filtration and washed with hexane. The solid was purified by silica gel flash chromatography using a 9:1 to 1:1 v/v hexane-ethyl acetate gradient through a 40-g Silicycle® flash silica cartridge to afford the title compound as a white solid (100 mg, 32% yield); Rf 0.50 with 1:1 v/v hexane-ethyl acetate; 1H-NMR (300 MHz; DMSO-d6) δ 9.12 (s, 2H), 7.50 (s, 1H), 7.43 (dd, 2H), 7.20-7.28 (m, 3H), 4.26 (q, 2H), 1.25 (t, 3H); MS (ESI−) m/z 309 (M−1); H-PGDS FPBA IC50: 1.3 μM; H-PGDS inhibitor EIA IC50: 0.13 μM.

1. temperaturewas subsequently cooled to room temperature
2. customThe off-white solid which had precipitated
3. filtrationwas collected by filtration
4. washwashed with hexane
5. customThe solid was purified by silica gel flash chromatography