Hydrochloric Acid → HCID 19423337, compound

Participants

Reaction Steps

3 g of 3,6-dimethyl-1-[2-(tetrahydropyran-2-yloxy)ethyl]-5,6,7,8-tetrahydro-1H-pyrido[4,3-d]pyrimidine-2,4-dione were dissolved in 150 ml of water and the pH was adjusted to 1 with conc. hydrochloric acid at 20°-25° C., with stirring. After stirring for 5 h at room temperature, 2 N sodium hydroxide solution was added dropwise to pH 8 and the reaction mixture was concentrated under reduced pressure. After azeotropic drying with ethanol, the residue was purified by chromatography on silica gel in a medium-pressure column with dichloromethane/methanol (volume ratio 85:15) and by recrystallization from dichloromethane/diethyl ether.

Provenance & Evidence