To a solution of 1-(3-((t-butyldimethylsilyloxy)methyl)phenyl)-3-(thiophen-2-yl)-1H-pyrazol-5-amine (available from ethyl 3-(5-amino-3-(thiophen-2-yl)-1H-pyrazol-1-yl)benzoate using general method C followed by protection with TBSCl) (0.5 g, 1.3 mmol) in THF (3 mL) was added pyridine (0.10 g, 1.3 mmol) and 1,2,3-trifluoro-4-isocyanatobenzene (0.27 g, 1.6 mmol). The reaction mixture was stirred at room temperature for 22 hours. Water was added and the solid was filtered, washed with H2O and dried under vacuum to obtain the crude product. To a solution of the crude product in THF was added TBAF (1.6 mL, 1.0 M). The reaction mixture was stirred at room temperature for 3 hours. The solvent was removed under reduced pressure. Ethyl acetate was added into the residue and then 1N—HCl (5 drops) was added. The organic layer was washed with water, dried (Na2SO4) and evaporated under reduced pressure to obtain the crude product. The crude was dissolved in methanol and the solid filtered and dried under vacuum to yield 1-(1-(3-(hydroxymethyl)phenyl)-3-(thiophen-2-yl)-1H-pyrazol-5-yl)-3-(2,3,4-trifluorophenyl)urea (0.42 g, 73% yield). 1H NMR (400 MHz, DMSO-d6): δ 9.13 (brs, 1H), 8.99 (s, 1H), 7.85 (m, 1H), 7.4-7.6 (m, 6H), 7.28 (m, 1H), 7.11 (dd, J=3.6, and 4.8 Hz, 1H), 6.86 (s, 1H), 5.39 (t, J=6.0 Hz, 1H), 4.62 (d, J=6.0 Hz, 2H); MS (EI) m/z: 445.0 (M+H+).
