5-[4-(2-Bromophenyl)-4H-1,2,4-triazol-3-yl]-2-phenylpyridine prepared in the Production Example 2 was dissolved in a mixture solvent of carbon tetrachloride (100 ml) and acetic acid (100 ml), followed by addition of n-bromosuccinimide (5.90 g), and refluxed under heating for 3 hours. After the reaction solution was cooled to ambient temperature, the solution was concentrated-under reduced pressure. Saturated aqueous sodium hydrogen carbonate solution was added to the resulting residue, and extracted with chloroform. Subsequently, the organic layer was dried over anhydrous magnesium sulfate. After the solvent was evaporated under reduced pressure, the resulting residue was purified by silica gel column chromatography (eluent: n-hexane/ethyl acetate=3/1), to afford the entitled compound as yellow solid (6.96 g, 69%). The physico-chemical values are as follows.
