HCID 22758819, compound → HCID 22758848, compound

Participants

Reaction Steps

A solution of ethyl 6,7-dihydro-10-methoxy-4-oxo-4H-pyrimido[2,1-a]isoquinoline-3-carboxylate (5.0 g., 0.0175 mole) in 48% hydrobromic acid (125 ml.) was refluxed for 4 hours. The solution was cooled and the yellow product collected, washed with water, and dissolved in warm 0.5 N NaOH (80 ml.). The basic solution was treated with decolorizing carbon, filtered and the filtrate acidified with hydrochloric acid. The precipitated material was washed on the filter successively with water, ethanol and acetone to give 3.5 g. (81% yield) of the title acid, m.p. 326°-327°.

Provenance & Evidence