After adding 3.32 g of potassium carbonate and 3.13 g of 1-fluoro-2-iodoethane to a solution of 5.5 g of [2-(2-fluoro-3-hydroxy-5-methoxyphenyl)-2-[4-(5-methyl-[1,2,4]oxadiazol-3-yl)phenylimino]-1-methylsulfanylethylidene]carbamic acid methyl ester in 100 ml of DMF, the mixture was stirred at room temperature for 15 hours. Water was added to the reaction mixture and extraction was performed with ethyl acetate. After washing the organic layer with water and saturated brine, it was dried over anhydrous magnesium sulfate. The desiccating agent was filtered off and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate-heptane) to give the title compound (5.88 g) as a yellow solid.
