2-(4-Hydroxyphenyl)-3,8-dimethyl-4(3H)-quinazolinone (500 mg, 1.88 mmol) was mixed with 1-chloro-3-bromopropane (326 mg, 2.07 mmol) and potassium carbonate (519 mg, 3.76 mmol) in DMF (5 ml), and stirred at 80° C. for 4 hours. After cooled to room temperature, potassium carbonate (519 mg, 3.76 mmol), potassium iodide (312 mg, 1.88 mmol) and piperidine (320 mg, 3.76 mmol) were added to the reaction solution, and further stirred at 80° C. for 12 hours. The reaction solution was diluted with ethyl acetate, then washed with aqueous 1 N sodium hydroxide solution and saturated saline water in that order, and the organic layer was dried with magnesium sulfate. The solvent was evaporated off, and the residue was purified through silica gel column chromatography (chloroform/methanol=5/1) and recrystallized from ethyl acetate to obtain the intended compound (63 mg, 8.6%) as a colorless solid.
