To a mixture of {4-[(3-methyl-5-phenyl-1H-pyrazol-1-yl)methyl]phenyl}methanol (139 mg, 0.5 mmol), methyl 3-(4-hydroxyphenyl)propanoate (90 mg, 0.5 mmol), triphenylphosphine (262 mg, 1.0 mmol) and dichloromethane (3 mL) was added dropwise diethyl azodicarboxylate (40% toluene solution, 435 mg, 1.0 mmol) with stirring at room temperature, and the mixture was stirred at room temperature for 1 hr. After completion of the reaction, the reaction mixture was purified by silica gel column chromatography (hexane:ethyl acetate=19:1-1:2) to give a yellow oil. The yellow oil was dissolved in methanol (3 mL) and tetrahydrofuran (3 mL), and 1 N aqueous sodium hydroxide solution (2 mL) was added. The mixture was stirred at room temperature for 1 hr. The reaction mixture was diluted with water, and neutralized with 1 N hydrochloric acid. The mixture was extracted with ethyl acetate. The ethyl acetate layer was dried using a Presep Dehydration tube (Manufactured by Wako. Pure Chemical Industries, Ltd.), and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=9:1-1:4) to give the title compound (90 mg, yield 42%, 2 steps) as colorless crystals.
