Under the conditions of Example 2(a), 3.012 g (10 mmol) of 2-[N-(4-fluoro-2-trifluoromethylphenyl)sulfamoyl]acetic acid, 1.252 g (10 mmol) of 2aminoethanesulfonic acid, 1.531 g (10 mmol) of hydroxybenzotriazole, hydrate, as well as 1.012 g (10 mmol) of triethylamine and 2.063 g (10 mmol) of dicyclohexylcarbodiimide are reacted and worked up analogously. The crude product is dissolved in distilled water, extracted with ethyl acetate, and converted into the free acid by treatment with acidic cation exchanger. The title compound is obtained by freeze-drying the aqueous solution.
