1.38 g (9.3 mmol) of 2-oxo-1-imidazolidinecarbonyl chloride was added to a solution of 2.17 g (9.3 mmol) of 1-aminocyclohexanecarboxylic acid phenylmethyl ester and 1.04 g (10 mmol) of triethylamine in 100 ml of chloroform, and the mixture was stirred at 60° C. for 4 days. The reaction solution was successively washed with water, a 10% aqueous potassium hydrogensulfate solution, a saturated aqueous sodium hydrogencarbonate solution and saturated brine, and it was dried with anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the obtained crystal was washed with diethyl ether to obtain 2.64 g (82%) of the title compound.
