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ChemicalBook CAS DataBase List 11β,16α,17,21-tetrahydroxypregna-1,4-diene-3,20-dione
13951-70-7

11β,16α,17,21-tetrahydroxypregna-1,4-diene-3,20-dione synthesis

10synthesis methods
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).11β,16α,17,21-tetrahydroxypregna-1,4-diene-3,20-dione
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Yield:13951-70-7 93.5%

Reaction Conditions:

with sodium hydroxide in methanol;dichloromethane at 0 - 5; for 1 h;Inert atmosphere;

Steps:

1.IV Stage-IV (Deacetylation)

Stage-IV (Deacetylation) Charge 5.83L of methanol (10 volume) and 5.83L of methylene chloride (10 volume) in a glass flask and added 583 gm of 16-HPN acetate(1.397mol) at RT. Start argon gas purging and cool to 0°C to 5°C under argon purging. Prepare 11.66 gm of sodium hydroxide (0.2915mol) solution in 0.583L of methanol (one volume) under argon purging and cool to 0°Cto 5°C. Sodium hydroxide solution is charge in reaction mass at 0°C to 5°C. Maintained the reaction mass at 0°C to 5°C for one hour, In-process check by TLC against 16-HPN acetate it should be nil. Adjust pH to neutral by 21.40ml of acetic acid (0.3742 mol); distill under reduced pressure while maintaining temperature below 40°C, till dry. Cool to ambient temperature and added 1.166L of purified water (02 volume). Cool to 0°C and maintain for one hour. Filter and wash with 300ml of purified water. Dry at 60°C (+5°C) till moisture content less than 1.0%, Yield=490gm (93.50%), HPLC Purity=98.97%, Single impurity= 0.40%.

References:

WO2016/120891,2016,A1 Location in patent:Page/Page column 13; 14

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