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Treatment of 18β-glycyrrhizic acid with a methanolic solution of HCl resulted in 1 : 1 mixture of methyl esters of 18α- and 18β-glycyrrhetinic acids. Benzoylation of the mixture led to methyl esters of 3-benzoyl-18α-glycyrrhetinic acid and 3-benzoyl-18β-glycyrrhetinic acid, which were separated by chromatography on silica gel. 18α-Glycyrrhetinic acid was prepared by alkaline hydrolysis of methyl 3-benzoyl-18α-glycyrrhetinate and was further used for the syntheses of 3-keto-18α-glycyrrhetinic acid and methyl esters of 18α-glycyrrhetinic acid and 3-keto-18α-glycyrrhetinic acid.