反应详情

5.6 g. of 2-chloro-5-oxo-6-carbethoxy-8-ethyl-5,8-dihydro-pyrido(2,3-d)pyrimidine, 5.2 g. of 1-β-hydroxyethyl piperazine and 50 cm3 of toluene are heated under reflux for 2 hours. After cooling, the solution is filtered to remove the hydrochloride which has precipitated, and the organic solution is diluted with its own volume of chloroform, is washed with water and dried (MgSO4). After evaporation, the residue is recrystallised from 40 cm3 of a mixture of isopropanol (1 volume) and isopropyl ether (2 volumes). 5.14 g. (68%) of 2-(4'-β-hydroxyethyl-piperazino)-5-oxo-6-carbethoxy-8-ethylpyrido(2,3-d)pyrimidine are obtained; melting point 172° C.

1. temperatureunder reflux for 2 hours
2. temperatureAfter cooling
3. filtrationthe solution is filtered
4. customto remove the hydrochloride which
5. customhas precipitated
6. additionthe organic solution is diluted with its own volume of chloroform
7. washis washed with water
8. dry with materialdried (MgSO4)
9. customAfter evaporation
10. customthe residue is recrystallised from 40 cm3 of a mixture of isopropanol (1 volume) and isopropyl ether (2 volumes)