In a round bottom flask under argon was placed 2-[4-(2-chloro-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-3-(trans-3-methyl-cyclobutyl)-propionic acid (100 mg, 0.29 mmol), dichloromethane (5 mL) and N,N-dimethylformamide (3 drops) at 25° C. To this mixture was added a 2.0M solution of oxalyl chloride in dichloromethane (180 μL, 0.36 mmol) dropwise, which resulted in gas evolution. The mixture was stirred for 15 min at 25° C. and then concentrated in vacuo. This residue was taken up in dichloromethane (5 mL) and added dropwise into another flask containing a solution of 1-(3-amino-pyrazol-1-yl)-2-methyl-propan-2-ol (prepared as in US20080021032, Example 80, 55 mg, 0.35 mmol), dichloromethane (5 mL) and 2,6-lutidine (180 μL, 0.58 mmol) at 25° C. and stirred for 1.5 h at 25° C. and then quenched with methanol. The mixture was diluted with dichloromethane and washed with a 1N aqueous hydrochloric acid solution. The organic layer was separated, dried over sodium sulfate and concentrated in vacuo with silica gel (2 g). Purification by Biotage flash chromatography (40S column, 25% ethyl acetate/hexanes) afforded 2-[4-(2-chloro-phenoxy)-2-oxo-2,5-dihydro-pyrrol-1-yl]-N-[1-(2-hydroxy-2-methyl-propyl)-1H-pyrazol-3-yl]-3-(trans-3-methyl-cyclobutyl)-propionamide (51 mg, 36%) as a light amber foam: HR-ES-MS m/z calculated for C25H31N4O4Cl [M+H]+ 487.2107, observed 487.2107; 1H NMR (500 MHz, DMSO-d6) δ ppm 1.06 (d, J=6.8 Hz, 9H), 1.48-1.57 (m, 1H), 1.65-1.73 (m, 1H), 1.75-1.83 (m, 1H), 1.88-2.01 (m, 3H), 2.14-2.26 (m, 1H), 2.28-2.37 (m, 1H), 3.90 (s, 2H), 4.20 (d, J=18.6 Hz, 1H), 4.58 (d, J=18.6 Hz, 1H), 4.66 (s, 1H), 4.73 (dd, J=9.3, 6.3 Hz, 1H), 4.78 (s, 1H), 6.44 (d, J=2.4 Hz, 1H), 7.37 (td, J=7.8, 1.5 Hz, 1H), 7.47 (td, J=7.8, 1.5 Hz, 1H), 7.51 (dd, J=7.8, 1.5 Hz, 1H), 7.53 (d, J=2.4 Hz, 1H), 7.65 (dd, J=7.8, 1.5 Hz, 1H), 10.75 (s, 1H).
