反应详情

To a solution of 1.0 g (4 mmol) of 3-ethoxycarbonyl-9-mercapto-4-oxo-4H-pyrido[1,2-a]pyrimidine (II-1) in 40 ml of dry methylene chloride is added 0.24 ml (2 mmol) of trichloromethyl chloroformate, and the resultant mixture is stirred for 10 min. and concentrated at room temperature under atmospheric pressure. To the residue are added 60 ml of dry methylene chloride and 0.77 ml (44 mmol) of 4-(2-methoxyphenyl)piperazine under ice-cooling, and the reaction mixture is stirred for 1 hour at room temperature. The reaction mixture is washed with N--HCl, saturated aqueous NaHCO3 and water in order, and the organic layer is dried and concentrated under reduced pressure. The oily residue in 1.94 g is chromatographed on a column of silica gel eluting with ethyl acetate to give 45 mg of Ia-2 (m.p. 154°-156° C. recrystallized from chloroform-n-hexane) and 516 mg of IV-2 (m.p. 151°-153° C. recrystallized from ethyl acetate).

1. concentrationconcentrated at room temperature under atmospheric pressure
2. temperaturecooling
3. washThe reaction mixture is washed with N
4. dry with materialHCl, saturated aqueous NaHCO3 and water in order, and the organic layer is dried
5. concentrationconcentrated under reduced pressure
6. customThe oily residue in 1.94 g is chromatographed on a column of silica gel eluting with ethyl acetate
7. customto give
8. custom45 mg of Ia-2 (m.p. 154°-156° C. recrystallized from chloroform-n-hexane) and 516 mg of IV-2 (m.p. 151°-153° C. recrystallized from ethyl acetate)