501 g of crude 16α-hydroxy prednisolone acetate is dissolved in 700 ml of dichloromethane and 700 ml of ethanol, then 1.5 ml of formic acid is added, 24 ml of 5% sodium hypochlorite aqueous solution is added dropwise, and the temperature is controlled at 15 °C, and the reaction is stirred to obtain the preliminary processed product; Add 150 ml of 5% sodium bisulfite aqueous solution to the above-mentioned preliminary treatment product, concentrate on removing the solvent, adding water to hydrolyze, and filter to obtain 45 g of 16α-hydroxyprednisolone acetate refined product; 45 g of 16α-hydroxyprednisolone acetate obtained above was dissolved in a mixed organic solvent of 250 ml of dichloromethane and 250 ml of methanol, stirred and cooled to 0 °C, 90 ml of 10% sodium sulfite aqueous solution was added, and the reaction was stirred. After completion, it was neutralized with 15% sulfuric acid by mass concentration; the mixed organic solvent was concentrated, watered out, filtered, and dried to obtain 36.5 g of 16α-hydroxyprednisolone (11β,16α,17,21-tetrahydroxypregna-1,4-diene-3,20-dione).
