HCID 14822471, compound → HCID 178481929, compound

Participants

Reaction Steps

A mixture of 20.9 g 7-methoxy-1-methyl-1H-pyrazolo[3,4-b]quinolin-3-amine (Example 7) and 420 ml 48% aqueous hydrobromic acid was stirred at reflux for 21 hours. The reaction mixture was quenched in ice-water and neutralized to pH 7.0 with ammonium hydroxide. The resulting yellow solid was collected by filtration, washed with water and recrystallized from 1100 ml absolute ethanol to provide 12.4 g (63%) 3-amino-1-methyl-1H-pyrazolo[3,4-b]quinolin-7-ol, orange-yellow solid, m.p. 288°-290° C. (decompn).

Provenance & Evidence