5 g of methyl 2,4-bis(2'-methoxybenzamido)-benzoate obtained in Example 9 was admixed with 250 ml of dioxane, 3 g of potassium hydroxide and 50 ml of water, followed by stirring the mixture at room temperature for 20 to 30 hours. The mixture was then poured into 1.5 l of ice-water containing 20 ml of acetic acid to precipitate crystals. The crystals were recovered by filtration, washed with water and recrystallized from ethanol-water to yield 3.6 g of 2,4-bis(2'-methoxybenzamido)-benzoic acid having a melting point between 232° - 233°C.
