3-(4-(2-Isocyanatopropyl)phenyl)-1-(4-(trifluoromethoxy)phenyl)-1H-1,2,4-triazole (C39) (0.17 g, 0.41 mmol) in acetonitrile (2 mL) was heated at 80° C. for 2 hours to ensure complete conversion to the isocyanate. The reaction was cooled and 1-(2-isopropyl-5-methylphenyl)thiourea (0.095 g, 0.46 mmol) and cesium carbonate (0.20 g, 0.60 mmol) were added. The reaction was stirred at room temperature for 3 days. The reaction was diluted with ethanol (2.5 mL) and sodium acetate (0.064 g, 0.78 mmol) and methyl 2-bromoacetate (0.05 mL, 0.53 mmol) were added. The reaction was heated at 65° C. for 2.5 hours. The reaction mixture was diluted with ethyl acetate and washed with water. The aqueous layer was extracted an additional time with ethyl acetate. The combined organic layers were dried over anhydrous sodium sulfate, filtered, and concentrated. The crude material was loaded onto a Celite® cartridge and purified by flash column chromatography using 0-100% ethyl acetate/B, where B=1:1 dichloromethane/hexanes, as eluent to afford the title compound as an off-white solid (0.054 g, 20%).
