In a dried reaction flask, the crude 2-(3-chloro-4-cyanophenyl)-3-cyclopentyl-3,3a,4,5-tetrahydro-2H-pyrazolo[3,4-f]quinoline-7-carboxylic acid (Compound 1) (0.432 g, about 0.972 mmol), morpholine (0.11 mL, 1.263 mmol), DIEA (0.18 mL, 1.04 mmol) and HATU (0.342 g, 0.899 mmol) were added to a mixed solvent of DMF (4.5 mL) and dichloromethane (4.5 mL). The mixture was stirred at room temperature for 7 hr. Water and ethyl acetate were added. The mixture was extracted with ethyl acetate. The combined organic phase was washed with water and brine, dried over anhydrous sodium sulfate, and concentrated at reduced pressure to produce a crude yellow solid, which was washed with methanol and ethyl ether to produce a purified product (0.371 g) in 77.9% yield.
