A solution of 4-(benzyloxy)-1-(1-(2-morpholinoethyl)-1H-indazol-5-yl)pyridin-2(1H)-one (37.0 mg, 0.086 mmol) in CH2Cl2 (0.7 mL) was treated with anhydrous HCl in diethyl ether (86 μL, 0.086 mmol, 1.0 M). After stirring at ambient temperature for 4.5 h, the solids were collected by filtration, dissolved in CH3CN and H2O, partially concentrated, then lyophilized to yield the title compound (25.6 mg, 64%) as a light yellow solid: 1H NMR (500 MHz, DMSO-d6) δ 10.50 (br s, 1H), 8.23 (s, 1H), 7.85 (d, J=8.5 Hz, 1H), 7.79 (s, 1H), 7.60 (d, J=7.5 Hz, 1H), 7.48-7.41 (m, 5H), 7.39-7.36 (m, 1H), 6.12 (dd, J=7.5, 3.0 Hz, 1H), 5.99 (d, J=3.0 Hz, 1H), 5.15 (s, 2H), 4.92 (br s, 2H), 3.99 (d, J=12.0 Hz, 2H), 3.70-3.68 (m, 4H), 3.53 (d, J=12.0 Hz, 2H), 3.19 (br m, 2H); ESI MS m/z 431 [M+H]+; HPLC (Method A) 99.3% (AUC), tR=13.9 min.
