Sodium Bicarbonate → HCID 13131705, compound

Participants

Reaction Steps

To a solution of 0.4 g. of sodium hydrogen carbonate in 20 ml. of water 1.0 g. (3.34 mmoles) of 9-anilino-6-methyl-4-oxo-6,7,8,9-tetrahydro-4H-pyrido[1,2-a]pyrimidine-3-carboxylic acid is added. The suspension is stirred at 80°-90° C., while air is bubbled through the mixture. The solids are dissolved and the solution is then stirred for half an hour and allowed to cool to room temperature. The pH-value is adjusted to 2 by the addition of a 5% by weight solution of hydrochloric acid. The precipitated crystals are filtered, washed with water and dried. 0.65 g. (65.5%) of 9-anilino-6-methyl-4-oxo-6,7-dihydro-4H-pyrido[1,2-a]pyrimidine-3-carboxylic acid is obtained. Melting point: 152°-154° C. After recrystallization from methanol the product melts at 172°-174° C. The substance when admixed with the product of Example 1 does not show melting point depression.

Provenance & Evidence