2-Ethoxy-3-{4-[2-(4-phenylmethanesulfonyloxyphenyl)ethoxy]phenyl}propanoic acid ethyl ester (described in Example 30) (0.21 g; 0.41 mmol) was dissolved in tetrahydrofuran (4 ml) and lithium hydroxide (0.021 g; 0.48 mmol) dissolved in water (1 ml) was added dropwise. The resulting solution was stirred at room temperature over night and then acidified with hydrochloric acid (2M). Extraction with ethyl acetate, drying with magnesium sulfate and evaporation gave 0.184 g (92%) of 2-ethoxy-3-{4-[2-(4-phenylmethanesulfonyloxy-phenyl)ethoxy]phenyl}propanoic acid as an oil.
