3-methyl-6-nitro-1-(2-pyridinyl)-1,9-dihydro-4H-pyrazolo[3,4-b]quinolin-4-one → 6-Amino-3-methyl-1-(2-pyridinyl)-1,9-dihydro-4H-pyrazolo[3,4-b]quinolin-4-one

Participants

Reaction Steps

A solution of 3-methyl-6-nitro-1-(2-pyridinyl)-1,9-dihydro-4H-pyrazolo[3,4-b]quinolin-4-one (4.64 g, 14.4 mmol) and 5% palladium-carbon (4.64 g, 50% hydrate) in N,N-dimethylformamide (400 mL) was stirred at room temperature under hydrogen atmosphere for 4 hours. The reaction solution was filtered to remove the catalyst, and the filtrate was evaporated under reduced pressure. The residue thus obtained was purified by silica gel column chromatography (chloroform:methanol=99:1 to chloroform:methanol=95:5) to give the title compound (2.86 g, 69% yield).

Provenance & Evidence