Combine 2-(4-bromomethyl-3-nitro-phenyl)-5-(4-chloro-phenyl)-[1,3,4]oxadiazole (894 mg, 2.27 mmol) and PPh3 (656 mg, 2.50 mmol) in DMF (13 mL) and heat to 95° C. under N2 for 4.5 h. Add 3-(4-formyl-3,5-dimethyl-phenyl)-2,2-dimethyl-propionic acid methyl ester (intermediate A in Example 1-62, 675 mg, 2.72 mmol) and K2CO3 (627 mg, 4.54 mmol), continue heating at 95° C. for 6.5 h. Allow the reaction to cool to room temperature. Dilute the cooled reaction with EtOAc (150 mL) and extract with water (50 mL). Dry the organic layer over Na2SO4 and evaporate the solvent. Purify the resulting oil by silica gel chromatography (10-45% EtOAc/HEP) to afford a yellow solid: (M+H)+ 546.1.
