To a suspension of N-{2-[5-(diphenylmethyl)-2-oxo-1(2H)-pyridinyl]ethyl}-3-hydroxybenzamide (60.0 mg) and K2CO3 (58.6 mg) in DMF (1.8 mL) was added dropwise ethyl bromoacetate (18.8 μL) at ambient temperature and the mixture was stirred at the same temperature for 14 hours. The resulting mixture was diluted with water (5.0 mL) and the aqueous solution was extracted with EtOAc (10.0 mL). The organic layer was washed successively with 1M HCl aqueous solution, saturated NaHCO3 aqueous solution and brine, dried over anhydrous MgSO4, filtered and evaporated in vacuo. The residue was purified by silica gel column chromatography (chloroform:MeOH=98:2) to give ethyl {3-[({2-[5-(diphenylmethyl)-2-oxo-1(2H) -pyridinyl]ethyl}amino)carbonyl]phenoxy}acetate (70 mg) as a colorless syrup.
