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ChemicalBook CAS DataBase List Meprednisone
1247-42-3

Meprednisone synthesis

1synthesis methods
-

Yield:1247-42-3 75%

Reaction Conditions:

with sodium hydroxide in ethanol at 20 - 40;Solvent;Reagent/catalyst;

Steps:

1.D D, synthetic methylprednisone
In a 2000 ml three-necked flask, 100 g of methylprednisone acetate, 1000 ml of 95% ethanol,Methylprednisolone acetate is completely dissolved at 20-25 degrees,Add 30g of caustic soda under stirring,Insulation at 35-40 degrees hydrolysis reaction 6-8 hours,TLC confirmed the end of the reaction, the reaction was completed, incubated at 25-30 degrees,Slowly add 600ml 30% hydrochloric acid solution,About 0.5-1.0 hours drip finished,And then continue to heat and neutralization reaction 0.5-1.0 hours,The system PH to maintain 6.5-7.0,Then concentrated under reduced pressure to recover 90-95% alcohol,Cooling and cooling to 0-15 degrees, adding 500ml of tap water,Stirring crystallization 1.5-2.5 hours, centrifuged,The filtrate is discharged into the wastewater treatment tank, the filter cake is washed and dried,Methyl prednisone crude 85g, HPLC content of 98.5%The weight yield of 85%; crude methyl prednisolone was dissolved in 950ml of alcohol, 5g activated carbon was added, and then heated to reflux for 1.0-1.5 hours,Hot filter press, the filter cake to 50ml alcohol secondary bubble wash sent to the manufacturer for recycling, the filtrate and lotion after the vacuum concentration of 90% alcohol concentration,Cooled to -5-0 degrees, stirred for 2-3 hours crystallization, filtered,The filter cake is rinsed with 5 ml of cold alcohol and dried to give methyl prednisone75g, HPLC content of 99.5%, the total weight of this step 75%The filtrate recovery of alcohol and mother liquor sets for the next batch of refining process.

References:

Hunan Kerui Bio-pharmaceutical Co., Ltd.;Gan Hongxing;Zuo Qianjin;Hu Aiguo;Xie Laibin CN107312052, 2017, A Location in patent:Paragraph 0010; 0012-0014

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