反应详情

The product from Example 1 step b) (1 g, 4.46 mmol) was suspended in xylene (25 ml) with pyrazine-2-hydrazide (074 g, 5.35 mmol) and triethylamine hydrochloride (0.61 g, 4.46 mmol) and the reaction mixture was heated at reflux for 2 days. The solvent was removed under high vacuum, and the residue was dissolved in dichloromethane, basified with sodium bicarbonate and the aqueous extracted with dichloromethane (2×150 ml). The combined organic layers were washed with brine, dried (MgSO4), filtered and evaporated. The residue was purified by silica gel chromatography using 0-40% ethyl acetate in dichloromethane as eluent to give the required product (0.249 g). 1H NMR (250 MHz, DMSO) δ 7.56 (5H, m), 8.43 (1H, s), 8.87 (1H, d, J=2.5 Hz), 8.96 (1H, d, J=2.5 Hz), 9.49 (1H, d J=2.5 Hz); MS (ES+) m/e 309 [MH+].

1. temperaturethe reaction mixture was heated
2. temperatureat reflux for 2 days
3. customThe solvent was removed under high vacuum
4. dissolutionthe residue was dissolved in dichloromethane
5. extractionthe aqueous extracted with dichloromethane (2×150 ml)
6. washThe combined organic layers were washed with brine
7. dry with materialdried (MgSO4)
8. filtrationfiltered
9. customevaporated
10. customThe residue was purified by silica gel chromatography