(±)-2-(trans-2-Hydroxycyclohexyl)-5-{[4-(1H-pyrazol-1-yl)phenyl]methyl}-2,5-dihydro-3H-pyrazolo[4,3-c]quinolin-3-one (Example 508, 0.15 g, 0.35 mmol) was dissolved in dichloromethane (5 mL), cooled to 0° C. and treated with bis(2-methoxyethyl)aminosulfur trifluoride (0.15 mL, 0.70 mmol, 2 equiv). The mixture was stirred at 0° C. for 30 minutes and then treated with additional bis(2-methoxyethyl)aminosulfur trifluoride (75 μL, 0.35 mmol, 1 equiv). After stirring for an additional 30 minutes, the mixture was treated with sodium bicarbonate (5 mL, aqueous saturated) and stirred vigorously for 15 minutes. The mixture was poured into sodium bicarbonate (75 mL, aqueous saturated) and extracted with dichloromethane (2×75 mL). The combined organic extracts were dried with sodium sulfate, filtered and concentrated in vacuo. The residue was purified by silica gel gradient chromatography (100:0 to 85:15; ethyl acetate:methanol), providing the titled compound: 1H-NMR (400 MHz, CDCl3) δ 8.39 (1H, s), 8.38-8.35 (1H, m), 7.89 (1H, d, J=2.5 Hz), 7.71 (1H, d, J=1.8 Hz), 7.69 (2H, d, J=8.6 Hz), 7.47-7.42 (2H, m), 7.40-7.36 (1H, m), 7.28-7.26 (2H, m), 6.46 (1H, dd, J=2.4, 1.8 Hz), 5.45 (2H, s), 5.03 (1H, dtd, J=49.9, 10.6, 5.0 Hz), 4.61-4.52 (1H, m), 2.34-2.27 (1H, m), 2.06-1.98 (2H, m), 1.91-1.80 (2H, m), 1.74-1.59 (1H, m), 1.52-1.43 (2H, m) ppm; high resolution mass spectrometry (ES+) m/z 442.2051 [(M+H)+; calculated for C26H25FN5O: 442.2038].
