Reaction Steps
To a solution of 2-[3-[5-chloro-2-(difluoromethoxy)phenyl]-4-[pyrazolo[1,5-a]pyrimidine-3-amido]-1H-pyrazol-1-yl]acetic acid (150 mg, 0.32 mmol) in DMF (10 mL) was added ethyl 1-[2-(piperazin-1-yl)ethyl]piperidine-4-carboxylate hydrochloride (199 mg, 0.65 mmol), DIEA (126 mg, 0.97 mmol), HATU (148 mg, 0.39 mmol). The resulting solution was stirred at room temperature overnight and concentrated under vacuum. The residue was passed through a short pad of silica gel eluting with 3% MeOH in DCM. The crude product was purified by Prep-HPLC with the following conditions (Prep-HPLC-005): Column, XBridge Prep C18 OBD Column, 5 um, 19*150 mm; mobile phase, water with 0.05% FA and MeCN (18.0% MeCN up to 27.0% in 10 min, up to 95.0% in 1 min, hold 95.0% in 1 min, down to 18.0% in 2 min); Detector, UV 254/220 nm. This resulted in 66.1 mg (27%) of the formic acid salt of ethyl 1-[2-[4-(2-[3-[5-chloro-2-(difluoromethoxy)phenyl]-4-[pyrazolo[1,5-a]pyrimidine-3-amido]-1H-pyrazol-1-yl]acetyl)piperazin-1-yl]ethyl]piperidine-4-carboxylate. LCMS (Method 24) [M+H]+=714.2, RT=2.42 min. 1H NMR (400 MHz, DMSO-d6) δ: (ppm) 9.76 (s, 1H), 9.34 (dd, 1H, J=1.6, 6.8 Hz), 8.69-8.68 (m, 2H), 8.31 (s, 1H), 7.62 (dd, 1H, J=2.8, 8.8 Hz), 7.56 (d, 1H, J=2.4 Hz), 7.46 (d, 1H, J=8.8 Hz), 7.29 (dd, 1H, J=4.4, 6.8 Hz), 7.08 (t, 1H, J=73.2 Hz), 5.23 (m, 2H), 4.03 (q, 2H, J=6.8 Hz), 3.50-3.47 (m, 4H), 2.88-2.85 (m, 2H), 2.52-2.51 (m, 6H), 2.47-2.26 (m, 3H), 2.12-2.07 (m, 2H), 1.80-1.78 (m, 2H), 1.60-1.55 (m, 2H), 1.16 (t, 3H, J=7.2 Hz).
