{5-[4-(1-Ethyl-1-{3-methyl-4-[2-(1-trimethylsilanyloxy-cyclopentyl)-ethyl]-phenyl}-propyl)-2-methyl-phenyl]-pyridin-3-yl}-acetic acid methyl ester (Example 114-(1); 26.8 mg, 0.046 mmol) was dissolved in tetrahydrofuran (0.4 mL). Tetra-n-butylammonium fluoride (1 M solution in tetrahydrofuran; 0.05 mL, 0.05 mmol) was added at room temperature, and the mixture was stirred for two hours. A saturated aqueous ammonium chloride solution and water were added to the reaction mixture, followed by extraction with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate and concentrated under reduced pressure. Then, the resulting residue was purified by silica gel chromatography (hexane only to hexane/ethyl acetate=3/1) to give the title compound (16.4 mg, 70%).
