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ChemicalBook CAS DataBase List Methylprednisolone acetate
53-36-1

Methylprednisolone acetate synthesis

4synthesis methods
-

Yield:-

Reaction Conditions:

Stage #1:11β,17α-dihydroxy-6α-methyl-1,4-pregnadiene-3,20-dione with iodine;calcium oxide in methanol;dichloromethane
Stage #2:acetic acid with potassium acetate in acetone at 45 - 50; for 2 h;

Steps:

1-3 Preparation of iodine:
Draw 400 parts of methanol into the iodine kettle,Add 70 parts of iodine,After stirring and dissolving, it is pumped into the reaction kettle.Add 180 parts of dichloromethane, 150 parts of dehydrogenation,40 parts of calcium oxide, neutralized to neutral by adding glacial acetic acid aqueous solution,Centrifugation, filtration, drying, and obtaining iodine;Preparation of the replacement:700 parts of acetone was taken in the reaction kettle.15 parts of glacial acetic acid,130 parts of potassium acetate,The reaction was carried out for 20 minutes, and 180 parts of the above iodine was added.The temperature is raised to 45 to 50 ° C, and the reaction is carried out for 2 hours.Concentrate the acetone under negative pressure to evaporate without acetone.Add water and water,Centrifugal, dry to obtain a crude replacement,Drying, pumping 1000 parts of methanol into the refining tank,The crude product of the replacement is introduced, and the temperature is raised and refluxed.The methanol is concentrated to a 1 times mother liquor under a negative pressure, crystallized, centrifuged, and dried to obtain a replacement;

References:

Yueyang Huanyu Pharmaceutical Co., Ltd.;Han Chaodong;Xin Junhao;Bie Chunmei;Qin Yu;Xue Xiaoxia;Yang Yuexia;Xu Runxing CN108912192, 2018, A Location in patent:Paragraph 0075; 0091-0096; 0100; 0106-0107; 0109; 0116-0119

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