METHOD FOR PREPARING GLYCYRRHIZIC ACID

摘要

FIELD: pharmaceutical industry and technology. ^ SUBSTANCE: invention relates to a method for preparing glycyrrhizic acid. Method for preparing glycyrrhizic acid involves extraction step of Ural licorice roots containing glycyrrhizic acid in the concentration 20 ± 2% with 1% solution of H2SO4 in acetone taken in the ratio of solid and liquid phase = 1:3 at temperature 20-22°C to obtain glycyrrhizic acid tripotassium salt by treatment of acetone extract with 10% solution of KOH in 96% ethanol followed by conversion of product to glycyrrhizic acid monopotassium salt by recrystallization from glacial acetic acid at temperature 95-98°C, recrystallization of monopotassium salt from the mixture ethanol - water (4:1; v/v) three times, treatment of the latter with 1% solution of H2SO4 at temperature 98-100°C and with chloroform at temperature 20-22°C. Method provides preparing glycyrrhizic acid with the higher content of the basic substance in using technical dried extract of licorice roots as the raw with the less content of glycyrrhizic acid. ^ EFFECT: improved preparing method. ^ 1 dwg, 2 ex