ChemicalBook CAS DataBase List Alfacalcidol

Alfacalcidol synthesis

4synthesis methods

Product Name:Alfacalcidol
CAS Number:41294-56-8
Molecular formula:C27H44O2
Molecular Weight:400.64

Bicyclo[3.1.0]hexan-3-ol, 1-[(1R,2E)-2-[(1R,3aS,7aR)-1-[(1R)-1,5-dimethylhexyl]octahydro-7a-methyl-4H-inden-4-ylidene]-1-methoxyethyl]-2-methylene-, (1R,3S,5S)-

67657-73-2
0 suppliers
inquiry

41294-56-8
378 suppliers
$32.00/1mg

Yield:41294-56-8 45%

Reaction Conditions:

Stage #1: (1S,6R)-3-deoxy-1-hydroxy-6-methoxy-3,5-cyclo-5,6-dihydrovitamin D₃with acetic acid in dimethyl sulfoxide at 20 - 50; for 1 h;Inert atmosphere;
Stage #2: with 4-Phenylurazole in ethyl acetate at 10; for 2 h;Inert atmosphere;Reagent/catalyst;Temperature;

Steps:

1-3 Example 3

A mixed solvent of 30 ml of dimethyl sulfoxide and 24 ml of glacial acetic acid was added to the reaction bottle, and 1α-hydroxy-3,5-cyclovitamin D3 (9 g, 21.7 mmol) was added at room temperature.Under nitrogen, the reaction was carried out at 50°C for 1 hour. The reaction solution was slowly poured into 500ml of sodium bicarbonate aqueous solution pre-cooled to 5°C, and extracted three times with ether (200ml).The organic phases were combined, washed successively with saturated aqueous sodium bicarbonate solution (150 ml) and saturated brine (150 ml), dried over anhydrous magnesium sulfate, filtered, and concentrated under reduced pressure to obtain alfacalcidol and 5,6-trans-1α-OH -Vitamin D3 (trans-isomer of alfacalcidol,Compound III) mixture, 100% yield, used directly in the next reaction.To the above reaction concentrate was added 100 ml of ethyl acetate and 4-phenyl-1,2,4-triazoline-3,5-dione (3.8 g, 21.7 mmol), and reacted at 10°C for 2 hours under nitrogen protection. ,The reaction solution was concentrated under reduced pressure, and the resulting residue was separated by column chromatography (ethyl acetate: n-hexane = 1:1) or recrystallized with 20 ml of methyl formate to obtain off-white alfacalcidol solid,The yield was 45% and the purity by HPLC was 99.7%.

References:

CN111072540,2020,A Location in patent:Paragraph 0028-0030; 0032-0034; 0036-0038