反应详情

Stannous chloride dihydrate (2.48 g, 0.011 mol) was added to a stirred solution of 2-(2-ethoxy-5-nitro-phenyl)-8-n-propylpyrido[3,2-d)pyrimidin-4(3H)-one (Example 10; 0.78 g, 0.0022 mol) in ethanol (10 ml) and the mixture was heated under reflux for 2 hours, allowed to cool, basified to pH 11 by the addition of 10% aqueous sodium hydroxide solution, and then extracted with methanol:dichloromethane (1:9, 3×50 ml). The organic extracts were combined, dried (MgSO4) and evaporated under vacuum, then the residue was chromatographed on silica gel (12 g) using a methanol in dichloromethane elution gradient (0-2% methanol). Trituration of the product with hexane:ethyl acetate gave the title compound as a colourless solid (0.51 g, 71%), m.p. 156-158° C.

1. temperaturethe mixture was heated
2. temperatureunder reflux for 2 hours
3. temperatureto cool
4. extractionextracted with methanol:dichloromethane (1:9, 3×50 ml)
5. dry with materialdried (MgSO4)
6. customevaporated under vacuum
7. customthe residue was chromatographed on silica gel (12 g)
8. washa methanol in dichloromethane elution gradient (0-2% methanol)