A mixture of [4-butyl-2-methyl-6-oxo-5-{[2′-(5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl)biphenyl-4-yl]methyl}pyrimidin-1(6H)-yl]acetic acid (0.12 g), morpholine (0.033 g), 1-hydroxybenzotriazole (0.035 g), 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride (0.05 g) and N,N-dimethylformamide (3 mL) was stirred at room temperature for 15 hr. The reaction mixture was diluted with ethyl acetate, washed with diluted hydrochloric acid and then with saturated brine, and dried over anhydrous magnesium sulfate. The solvent was evaporated under reduced pressure and the residue was purified by silica gel column chromatography to give the title compound as colorless crystals (0.080 g, 59%).
