A mixture of [4-(6-amino-5-benzothiazol-2-ylpyridin-3-yl)-pyrazol-1-yl]-acetic acid (5.00 mg, 0.0142 mmol), morpholine (10.0 mg, 0.11 mmol), TBTU (9.14 mg, 0.0284 mmol), DIPEA (0.02 mL, 0.1 mmol) and DMF (2 mL, 0.03 mol) was stirred at rt for 10 min. The solution was transferred to a separatory funnel, diluted with EtOAc and washed 3× with water. The organic layer was concentrated in vacuo and loaded onto a prep TLC plate, eluting with 5% MeOH/DCM. The band containing the pure product was filtered off using 1:1 MeOH/DCM, and the filtrate was concentrated in vacuo to afford the title compound as a yellow solid. 1H NMR (400 MHz, CD3OD): δ=3.60-3.64 (m, 4H), 3.72 (dt, J=12.8, 4.7 Hz, 4H), 5.17 (s, 2H), 7.40-7.45 (m, 1H), 7.48-7.54 (m, 1H), 7.85 (s, 1H), 7.94-7.98 (m, 2H), 8.02 (d, J=7.8 Hz, 1H), 8.16 (d, J=2.3 Hz, 1H), 8.30 (d, J=2.3 Hz, 1H). MS (ES+): m/z=421.12 (100) [MH+]. HPLC: tR=2.79 min (ZQ3, polar—5 min).
