Monoalkylation of 1-phenylpyrazolo[3,4-d]pyrimidine-4,6-dithione (I) with 2-bromopropionamide (II) produced selectively the 6-substituted compound (III). Subsequent methylation of the free 4-mercapto group yielded the 4-methylsulfanyl derivative (IV). Finally, displacement of the methylsulfanyl group of (IV) with ethanolic ammonia in a sealed tube at 100 C furnished the title amino compound.

Monoalkylation of 1-phenylpyrazolo[3,4-d]pyrimidine-4,6-dithione (I) with 2-bromopropionamide (II) produced selectively the 6-substituted compound (III). Subsequent methylation of the free 4-mercapto group yielded the 4-methylsulfanyl derivative (IV). Finally, displacement of the methylsulfanyl group of (IV) with ethanolic ammonia in a sealed tube at 100 C furnished the title amino compound.