反应详情

5.14 g. of the ester are added to an aqueous-alcoholic solution of sodium hydroxide (N NaOH: 15 cm3, ethanol: 10 cm3); the mixture is stirred for 2 hours at ordinary temperature and is then brought to pH 6 by adding acetic acid. After concentration to dryness in vacuo, the residue is taken up in a saturated solution of sodium acetate (50 cm3) and is extracted with chloroform (3 × 50 cm3). After drying (MgSO4), the solvent is evaporated and the residue is recrystallised from 80 cm3 of ethanol. 2.4 g. (53.3%) of 2-(4'-β-hydroxyethyl-piperazino)-5-oxo-8-ethyl-5,8-dihydro-pyrido(2,3-d)pyrimidine-6-carboxylic acid are obtained; melting point 222° C.

1. concentrationAfter concentration to dryness in vacuo
2. extractionis extracted with chloroform (3 × 50 cm3)
3. dry with materialAfter drying (MgSO4)
4. customthe solvent is evaporated
5. customthe residue is recrystallised from 80 cm3 of ethanol