To a 50 mL round-bottomed flask was added 4-(1,4-dimethyl-1H-pyrazol-5-yl)-5-methyl-2-thiophenecarboxylic acid (170 mg, 0.68 mmol), 2-{(2S)-2-amino-3-[3-(trifluoromethyl)phenyl]propyl}-1H-isoindole-1,3(2H)-dione (256 mg, 0.67 mmol) [prepared according to the procedure of Preparation 6 except substituting N-{[(1,1-dimethylethyl)oxy]carbonyl}-3-(trifluoromethyl)-L-phenylalanine (4.98 g, 15.0 mmol) for N-{[(1,1-dimethylethyl)oxy]carbonyl}-2-(trifluoromethyl)-L-phenylalanine] and PyBrop (387 mg, 0.83 mmol) in chloroform (7 mL). DIEA (600 μL, 3.44 mmol) was added and the reaction stirred overnight at room temperature. The mixture was adsorbed onto silica and purified via column chromatography (25-70% EtOAc/Hex) affording the title compound (311 mg, 0.55 mmol, 80%): LC-MS (ES) m/z=567 (M+H)+.
