HCID 16226437, compound → HCID 57717551, compound

Participants

Reaction Steps

A solution of 2-butyl-1-[2-(propylsulfonyl)ethyl]-2H-pyrazolo[3,4-c]quinolin-4-amine (prepared as described in Example 60, 0.50 g, 1.3 mmol) in trifluoroacetic acid (6 mL) was treated with platinum (IV) oxide (0.5 g) and shaken under hydrogen pressure (50 psi, 3.4×105 Pa) for 20 hours on a Parr apparatus. The reaction mixture was filtered through a layer of CELITE filter agent, and the CELITE filter agent was rinsed with dichloromethane (100 mL) until the rinses were clear. The filtrate was concentrated under reduced pressure. The oil was suspended in water (20 mL) and treated with 50% aqueous sodium hydroxide to adjust the mixture to pH 14, causing a precipitate to form. The mixture was stirred for 1 hour, then the precipitate was isolated by filtration and washed with water. The white powder was recrystallized from acetonitrile (5 mL). The crystals were isolated by filtration, washed with acetonitrile, and dried under vacuum at 65° C. to afford 0.40 g of 2-butyl-1-[2-(propylsulfonyl)ethyl]-6,7,8,9-tetrahydro-2H-pyrazolo[3,4-c]quinolin-4-amine as white crystals, mp 173-175° C. 1H NMR (300 MHz, DMSO-d6) δ 6.02 (bs, 2H), 4.28 (t, J=7.5 Hz, 2H), 3.43-3.37 (m, 4H), 3.19-3.14 (m, 2H), 2.85 (bs, 2H) 2.56 (bs, 2H), 1.85 (pentet, J=7.5 Hz, 2H), 1.77-1.70 (m, 6H), 1.33 (sextet, J=7.5 Hz, 2H), 1.00 (t, J=7.5 Hz, 3H), 0.93 (t, J=7.5 Hz, 3H);

Provenance & Evidence