Hydrochloric Acid → Hydrochloric Acid

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-Amino-1,6-dihydro-5-nitro-6-oxo-α-(3-thienylmethyl)-4-pyrimidineacetonitrile prepared above (5.0 g) in 1N NaOH (300 mL) is added sodium dithionite (20 g). The reaction mixture is heated for 30 min at 90° C. and then is acidified (pH 1) with conc HCl while still hot. The reaction mixture is cooled and neutralized with ammonium hydroxide. The resulting precipitate is collected by filtration, washed with cold water and dried under vacuum. The crude product is added to 100 mL conc HCl in small portions with stirring and the hydrochloride salt is collected by filtration. The product is recrystallized from 1N HCl to give 2,6-Diamino-3,5-dihydro-7-(3-thienylmethyl)-4H-pyrrolo [3,2-d]pyrimidin-4-one as the monohydro-chloride salt (2.35 g), mp>185° C. (dec). ##STR19##

Provenance & Evidence