Ethyl chloroformate (0.029 mL) was added to a 0° C. solution of 4-chloro-3-hydroxybenzoic acid (50 mg) and 4-methylmorpholine (0.092 L) in dichloromethane (2 mL). The reaction was stirred for two hours and then was treated with the compound prepared in Example 9 (79 mg). The reaction was stirred overnight, then diluted with ethyl acetate and washed twice with a saturated aqueous sodium bicarbonate solution. The organic phase was dried over anhydrous magnesium sulfate and concentrated. The residue was purified by column chromatography on silica gel (ethyl acetate:hexane=1:9, then methanol:concentrated aqueous ammonia:ethyl acetate=2:3:95) to obtain the title compound (60 mg) having the following physical data.
