Phosphoric Acid → HCID 178516367, compound

Participants

Reaction Conditions

Reaction Steps

A mixture of 3.91 g of 6-ethoxycarbonyl-7-hydroxy-3-(4-phenylthiophenyl)-pyrazolo[1,5-a]pyrimidine obtained in Example 1 and 30 ml of 85% phosphoric acid was heated in a heating bath to 170° C., and stirred for 30 minutes, and the mixture gradually developed foams, and the foams were about to cease, the reaction solution turned to a dark red color. Stopping the heating bath, 200 ml of water was added, and after letting stand for 30 minutes while ice-cooling, the precipitate was filtered, washed in water and dried, and 2.55 g of the title compound was obtained.

Provenance & Evidence