Anisole (18.0 vol), compound 9 (1.25 equiv.), and water (9.5 vol) were mixed and then heated to 85 °C, after which 62.5% sulfuric acid aqueous solution (6.0 equiv.) was added dropwise over 2 h. The mixture was stirred at 85 °C for 2.5 h. After the organic layer was separated, the obtained aqueous solution was washed with anisole. The aqueous solution was adjusted to weak acidic condition with 48% sodium hydroxide aqueous solution. A solution of compound 7 dissolved in 2-methyltetrahydrofuran (15.0 vol) was added dropwise to the aqueous solution. An aqueous solution of tripotassium phosphate (2.3 equiv.) dissolved in water (3.5 vol) was added dropwise to the mixture. After stirring at 25 °C for 1 h, the mixture was heated to 50 °C and then stirred for 6 h. After the aqueous layer was separated, 2-methyltetrahydrofuran (5.0 vol) and 1 N hydrochloric acid/2.5% sodium chloride aqueous solution were added to the organic solution. After the aqueous layer was separated, which was followed by the filtration through microcrystalline cellulose. The microcrystalline cellulose was washed with 2-methyltetrahydrofuran (3.0 vol). 2% sodium chloride aqueous solution was added to the mixed filtrate, and then the aqueous layer was separated, which was followed by the filtration through activated carbon. The activated was washed with 2-methyltetrahydrofuran (15.0 vol). The mixed filtrate was concentrated to 9.5 vol, and then the resulting slurry was stirred for at 25 °C 1 h. n-Heptane (15.0 vol) was added dropwise to the slurry, and then the slurry was stirred at 25 °C for 2 h and filtrated. The filtrated solid was washed with a mixture of 2methyltetrahydrofuran (1.5 vol) and n-heptane (2.5 vol), and then n-heptane (4.0 vol).