反应详情

After repetition of the previous reaction, a mixture of 2-amino-5-methoxy-4-(3-pyrrolidin-1-ylpropoxy)benzamide hydrochloride (5.92 g), Gold's reagent (3.5 g) and dioxane (50 ml) was heated to reflux for 5 hours. Acetic acid (0.7 ml) and sodium acetate (1.33 g) were added and the reaction mixture was heated to reflux for a further 5 hours. The mixture was allowed to cool to ambient temperature and evaporated. The residue was dissolved in water, adjusted to pH8 with 2N aqueous sodium hydroxide solution and purified on a Diaion HP20SS resin column eluting with methanol (gradient 0-50%) in water. The fractions containing product were concentrated by evaporation and then freeze dried to give 6-methoxy-7-(3-pyrrolidin-1-ylpropoxy)-3,4-dihydroquinazolin-4-one (4.55 g); NMR Spectrum: (DMSOd6 and CF3CO2D) 1.9 (m, 2H), 2.0-2.1 (m, 2H), 2.2-2.3 (m, 2H), 3.05 (m, 2H), 3.34 (t, 2H), 3.6-3.7 (br s, 2H), 3.94 (s, 3H), 4.27 (t, 2H), 7.31 (s, 1H), 7.55 (s, 1H), 9.02 (s, 1H).

1. customAfter repetition of the previous reaction
2. temperaturewas heated
3. temperatureto reflux for 5 hours
4. temperaturethe reaction mixture was heated
5. temperatureto reflux for a further 5 hours
6. customevaporated
7. dissolutionThe residue was dissolved in water
8. custompurified on a Diaion HP20SS resin column
9. washeluting with methanol (gradient 0-50%) in water
10. additionThe fractions containing product
11. concentrationwere concentrated by evaporation
12. customfreeze dried