A mixture of the mixture (4.0 g) of ethyl (2E)-3-[1-benzyl-5-(4-fluorophenyl)-1H-pyrazol-4-yl]acrylate and ethyl (2E)-3-[1-benzyl-3-(4-fluorophenyl)-1H-pyrazol-4-yl]acrylate produced in Reference Example 32, a 2N aqueous sodium hydroxide solution (11 ml) and methanol (20 ml) was stirred at 60° C. for 14 hrs. 1N Hydrochloric acid (22 ml) was poured into the reaction mixture. The precipitated solids were collected by filtration, washed with water and isopropyl ether and dried with airflow to give a mixture (3.5 g, 95%) of (2E)-3-[1-benzyl-5-(4-fluorophenyl)-1H-pyrazol-4-yl]acrylic acid and (2E)-3-[1-benzyl-3-(4-fluorophenyl)-1H-pyrazol-4-yl]acrylic acid as a powder.
