142865-40-5

Upstream product

• 67-97-0 cholecalciferol 
• 67-97-0 (5E)-cholecalciferol 
• 86307-24-6 (1S,5R)-5-(tert-Butyl-dimethyl-silanyloxy)-3-[2-[(1R,3aS)-1-((R)-1,5-dimethyl-hexyl)-7a-methyl-octahydro-inden-(4E)-ylidene]-eth-(E)-ylidene]-2-methylene-cyclohexanol 
• 87649-55-6 tert-Butyl-{(S)-3-[2-[(1R,3aS)-1-((R)-1,5-dimethyl-hexyl)-7a-methyl-octahydro-inden-(4E)-ylidene]-eth-(E)-ylidene]-4-methylene-cyclohexyloxy}-dimethyl-silane 
• 67657-73-2 (1S,6R)-3-deoxy-1-hydroxy-6-methoxy-3,5-cyclo-5,6-dihydrovitamin D₃ 
• 71726-02-8 (S)-3-[(R)-1-((R)-1,5-Dimethyl-hexyl)-7a-methyl-octahydro-inden-(4E)-ylidenemethyl]-2,2-dioxo-2,3,4,5,6,7-hexahydro-1H-2λ⁶-benzo[c]thiophen-5-ol 
• 86307-24-6 (1S,5R)-5-(tert-Butyl-dimethyl-silanyloxy)-3-[2-[(1R,3aS)-1-((R)-1,5-dimethyl-hexyl)-7a-methyl-octahydro-inden-(4E)-ylidene]-eth-(Z)-ylidene]-2-methylene-cyclohexanol 

Downstream Products

• 41294-56-8 1α-hydroxyvitamin D3 
• 112670-85-6 (1R,3aS,7aR)-4-[2-[(3S,5R)-3,5-Bis-(tert-butyl-dimethyl-silanyloxy)-2-methylene-cyclohex-(E)-ylidene]-eth-(E)-ylidene]-1-((R)-1,5-dimethyl-hexyl)-7a-methyl-octahydro-indene 

Relevant academic research and scientific papers

A modified synthesis of the antiosteoporosis drug alfacalcidol via a key photochemical transformation of 1α-5,6-Trans-Vitamin D3

Alfacalcidol (1α-hydroxyvitamin D3) is an important clinical drug for the treatment of osteoporosis. Its practical synthesis has been intensively pursued across academia. The difficulties of separating 5,6-cis and 5,6-trans isomers in the current process was avoided by photochemical transformation of the 5,6-trans isomer into the 5,6-cis isomer. Employing vitamin D3 as a starting material, alfacalcidol was obtained by a five-step reaction sequence of esterification, cyclization, oxidation, solvolysis ring-opening, and subsequent photochemical reaction. The overall yield has been greatly improved from 17% to 31%. Georg Thieme Verlag Stuttgart New York.

Improved preparation method of alfacalcidol

The invention discloses an improved preparation method of alfacalcidol. The preparation method is characterized by comprising the following steps: starting from 1 alpha-OH-3,5-cyclized vitamin D3, directly carrying out ring-opening hydrolysis without an acetate intermediate to obtain alfacalcidol and a trans-isomer thereof, carrying out a Diels-Alder reaction, selectively reacting with the trans-isomer, and carrying out column chromatography separation or methyl formate recrystallization to obtain a pure alfacalcidol product. The method is simple and convenient to operate, mild in reaction condition and high in total yield, and is suitable for large-scale synthesis of products.

Method for preparing high-purity 1 alpha-hydroxyvitamin D3

The invention discloses a method for preparing high-purity 1 alpha-hydroxyvitamin D3. The method comprises the following steps of (1) carrying out esterification; (2) carrying out cyclization; (3) carrying out oxidization; (4) carrying out ring opening; (5) carrying out photochemical isomerisation; (6) utilizing molecular sieve zeolite to carry out chiral purification and treatment on crude 1 alpha-hydroxyvitamin D3, and finally, carrying out recrystallization with an ethyl acetate-n-hexane system to obtain the high-purity 1 alpha-hydroxyvitamin D3. According to the method, by using a liposoluble solvent to replace pyridine and using an organic alkaline catalyst, under the condition with equivalent yield, the reaction temperature is changed from low temperature to room temperature, the reaction time is shortened, the pyridine with large pungent smell is avoided from using, and thus the economic practicability of the technology is greatly improved.