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ChemicalBook CAS DataBase List Prednisone Impurity 13
91160-89-3

Prednisone Impurity 13 synthesis

3synthesis methods
50.5 g of 2-((8S,10S,13S,14S,16R,17S)-16,17-dihydroxy-10,13-dimethyl-3-oxo-6,7,8,10,12,13,14,15,16,17-decahydro-3H-cyclopenta[a]phenanthren-17-yl)-2-oxoethyl acetate was dissolved in 1500 ml of acetone, 70 ml of 5% perchloric acid was added, the temperature was lowered to 0°C with stirring, and 45 g of N-bromosuccinimide was added and stirred After the reaction was completed, 50 ml of 20% sodium sulfite aqueous solution was added, the acetone was concentrated, the water was separated, filtered, and dried to obtain 62 g of Prednisone Impurity 13 (9α-bromo-11β,16α,17α,21-tetrahydroxypregnane-1,4-diene-3,20-dione-21-acetate).
Prednisone Impurity 13
77017-20-0 Synthesis
16alpha,17,21-trihydroxypregna-1,4,9(11)-triene-3,20-dione 21-acetate

77017-20-0
42 suppliers
$640.00/10mg

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Yield:91160-89-3 94.5%

Reaction Conditions:

with N-Bromosuccinimide;perchloric acid in tetrahydrofuran;water at 20; for 1 h;Large scale;

Steps:

2 Example 2: 9α-bromo-11β,16α,17α,21-tetrahydroxypregnane-1,4-diene-3,20-dione-21-acetate (intermediate 4)

Water (6L), NBS (0.62kg, 3.48mol)And 1.75 mol/L perchloric acid (3.3 L, 5.78 mol) was added to Intermediate 3 (1 kg, 2.50 mol)The solution was stirred at room temperature for 1 h in THF (26 L).The reaction solution was neutralized with a saturated sodium hydrogen carbonate solution (3 L), and added to purified water (100 L).Stirring at room temperature, suction filtration,The filter cake was washed with water to give Intermediate 4 (1.17 kg, 94.5%).

References:

CN109384827,2019,A Location in patent:Paragraph 0039; 0042-0043