In DMF (10 ml) was dissolved 1-ethyl-3-methylxanthine (385 mg), a production process for which is described in Journal of American Chemical Society 75, 114, 1953. To this solution were added potassium carbonate (415 mg) and 4-(4-chlorobenzoyl)benzyl bromide (619 mg) and the mixture was stirred at room temperature for 14 hours. This reaction mixture was diluted with water and extracted with ethyl acetate. The extract was washed with saturated aqueous NaCl solution and dried over anhydrous sodium sulfate and the solvent was distilled off. The residue was purified by silica gel column chromatography (hexane: ethyl acetate=1:4) and recrystallized (ethyl acetate-ether-hexane) to provide the title compound as white powder (207 mg, 25%).
