To a solution of 4′-{[1-(4-hydroxyphenyl)-2-methyl-6-oxo-4-propyl-1,6-dihydropyrimidin-5-yl]methyl}biphenyl-2-carbonitrile (1.0 g) and bromocyclobutane (1.1 mL) in N,N-dimethylformamide (10 mL) was added cesium carbonate (1.5 g), and the mixture was stirred at 80° C. for 5 hr. The reaction mixture was allowed to cool to room temperature, ethyl acetate and water were added, and the mixture was extracted with ethyl acetate. The organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate. The solvent was evaporated and the residue was purified by silica gel column chromatography to give the title compound as a pale-yellow viscous substance (1.02 g, 91%).
