Reaction Steps
A solution of 10-[(4-methylphenyl)sulfonyl]-10H-pyrazolo[1′,5′:1,2]imidazo[4,5-c]quinoline (0.55 g, 1.5 mmol) in 1,2-dichloroethane (15 mL) was placed in a 48 mL heavy wall glass pressure flask and treated with 3-chloroperoxybenzoic acid (0.56 g, 2.3 mmol). After 1.5 h the reaction was treated with concentrated NH4OH (5 mL, 30%); the flask was sealed and heated to 70° C. Once at temperature, p-toluenesulfonyl chloride (0.31 g, 1.7 mmol) was quickly added, the flask was resealed and heated to 75° C. After 1 h additional NH4OH (1 mL) and p-toluenesulfonyl chloride (50 mg) were added and the flask heated for another hour. After 2 h total, the flask was cooled to ambient temperature, and the reaction mixture was diluted with chloroform (15 mL) and water (10 mL). The phases were separated and the organic portion was washed with 10% Na2CO3 aqueous solution (10 mL) and water (10 mL). The combined aqueous washes were back-extracted with chloroform (20 mL). The combined organic extracts were washed with brine (10 mL), dried over Na2SO4, filtered, and concentrated under reduced pressure to yield an orange solid. The solid was recrystallized twice from acetonitrile to yield 0.14 g of 10-[(4-methylphenyl)sulfonyl]-10H-pyrazolo[1′,5′:1,2]imidazo[4,5-c]quinolin-6-amine as tan crystals, mp 204-206° C.; 1H NMR (500 MHz, DMSO-d6) δ 8.55-8.53 (m, 1H), 8.13 (d, J=2.3 Hz, 1H), 7.68-7.67 (m, 2H), 7.66-7.64 (m, 2H), 7.41-7.389 (m, 1H), 7.35 (d, J=8.2 Hz, 2H), 7.24 (s, 2H), 6.64 (d, J=2.0 Hz, 1H), 3.29 (s, 3H); 13C NMR (125 MHz, DMSO-d6) δ 148.1, 147.6, 147.4, 142.8, 131.7, 131.3, 131.0, 130.9, 128.4, 127.2, 125.9, 125.5, 123.4, 122.7, 111.3, 90.8, 21.5; MS (APCI) m/z 378.06 (M+H)+; Anal. Calcd for C19H15N5O2S: C, 60.47; H, 4.01; N, 18.56. Found: C, 60.21; H, 3.84; N, 18.52.
