反应详情

温度

195 °C

To polyphosphoric acid, preheated to 130° C., was added in one portion an intimate mixture of the product of Example 1 Step 2 (206 mg, 1.5 mmol) and 3-aminopyrazine-2-carboxylic acid (230 mg, 1.65 mmol). The temperature was increased to 195° C. for 1 hour and then cooled back to 130° C. for a further 1 hour. The viscous oil was poured on to ice containing saturated sodium carbonate solution and diethyl ether (5 ml) and the aqueous solution was extracted with chloroform (×5). The combined organic extracts were washed with brine, dried over anhydrous magnesium sulfate and concentrated in vacuo. The crude solid was purified by silica gel chromatography eluting with a gradient of dichloromethane to 0.880 ammonia:ethanol:dichloromethane (1:9:40), to afford the title compound, (20 mg, 6%); MS (ES+) m/e 241 [M+H]+.

1. custompreheated to 130° C.
2. additionwas added in one portion
3. temperaturecooled back to 130° C. for a further 1 hour
4. extractionthe aqueous solution was extracted with chloroform (×5)
5. washThe combined organic extracts were washed with brine
6. dry with materialdried over anhydrous magnesium sulfate
7. concentrationconcentrated in vacuo
8. customThe crude solid was purified by silica gel chromatography
9. washeluting with a gradient of dichloromethane to 0.880 ammonia:ethanol:dichloromethane (1:9:40)