EP1419775A1 — Pharmaceutical preparations containing aminobenzene-sulfonic acid derivatives as the active ingredient

USPTO Abstract

A stable pharmaceutical preparation containing an aminobenzenesulfonic acid derivative represented by the following formula (I) known as a therapeutic agent for cardiac insufficiency: or a salt thereof, or a hydrate thereof or a solvate thereof as an active ingredient, wherein each production of substance A having a retention time of about 6.4 minutes in a high performance liquid chromatography, substance B having a retention time of about 15.6 minutes in the high performance liquid chromatography, and substance C having about 22.8 minutes in the high performance liquid chromatography is substantially suppressed, wherein said high performance liquid chromatography is performed at a controlled flow rate for elution so as to give a retention time of about 7 minutes of said active ingredient by using an ultraviolet absorptiometer at 220 nm, an octylsilylated silica gel packed column (4 mm x 250 mm) at 40°C, and a mobile phase prepared by dissolving 7.8 g of sodium dihydrogenphosphate dihydrate in 1000 mL of a mixture of water/acetonitrile (6:1) after said pharmaceutical preparation is extracted with a diluent prepared by dissolving 7.8 g of sodium dihydrogenphosphate dihydrate in 1000 mL of a mixture of water/acetonitrile (6:1) and adjusting a pH to 7.0 with addition of 8 mol/L sodium hydroxide solution.