41461-10-3

Upstream product

• 2233-29-6 2,3,4-lutidine 
• 77-48-5 1,3-dibromo-5,5-dimethylimidazolidine-2,4-dione 
• 35339-68-5 (5-Cholesten-1α,3β-diol)-diacetat 
• 38774-63-9 (20S)-cholest-5-en-3β-yl acetate 
• 57566-18-4 Acetic acid (3S,8S,9S,10R,13R,14S,17R)-7-bromo-17-((S)-1,5-dimethyl-hexyl)-10,13-dimethyl-2,3,4,7,8,9,10,11,12,13,14,15,16,17-tetradecahydro-1H-cyclopenta[a]phenanthren-3-yl ester 
• 1576-35-8 toluene-4-sulfonic acid hydrazide 
• 60008-81-3 1α,3β-diacetoxycholest-5-ene-7-one 
• 65061-67-8 1α,2α-Epoxy-cholest-5-en-3β-ol 
• 26358-75-8 1α,3β-dihydroxycholest-5-ene 
• 142867-61-6 C₃₉H₅₃N₃O₆ 

Downstream Products

• 43217-89-6 1α,3β-dihydroxycholesta-5,7-diene 
• 41294-56-8 1α-hydroxyvitamin D3 

Relevant academic research and scientific papers

1-α-hydroxy vitamin D compounds and process for preparing same

The invention provides novel 1α-hydroxy vitamin D compounds and a method for their preparation from 1α-hydroxy-25-hydrogen cholesta-5,7-dienes by irradiation and isomerization techniques. The invention also includes the said 1α-hydroxy-25-hydrogen-cholesta-5,7-dienes and the corresponding cholest-5-enes. The new compounds may be obtained in a crystalline form substantially free from isomeric or other impurities arising from manufacture.

Process for the preparation of active-type vitamin D3 compounds

The present invention relates to a novel process for the preparation of active-type vitamin D3 compounds and their intermediates. In accordance with the present invention, a large amount of an active-type vitamin D3 compounds, for example 1α-hydroxycholecalciferol, 1α,25-dihydroxycholecalciferol and the like, is efficiently prepared with high industrial advantages by a novel processes, which comprises (i) reacting hydroxycholesta-5-enes having the hydroxyl groups protected with lower alkoxycarbonyl group as a starting material with allylic brominating agent and dehydrobrominating agent to prepare the corresponding hydroxycholesta-5,7-dienes, (ii) exposing the hydroxycholesta-5,7-dienes to ultraviolet irradiation or to a combination of the irradiation with thermal isomerization to obtain a mixture of the unreacted hydroxycholesta-5,7-dienes and previtamin D3 compounds or a mixture of the unreacted hydroxycholesta-5,7-dienes and the protected active-type vitamin D3 compounds, (iii) separating the mixture into the unreacted hydroxycholesta-5,7-dienes and previtamin D3 compounds or the protected active-type vitamin D3 compounds, (iv) recycling the unreacted hydroxycholesta-5,7-dienes as reuse and (v) thermally isomerizing the remaining compounds and/or splitting off the protective groups. The process for the preparation of active-type vitamin D3 compounds, in the present invention, is of very high industrial value, capable of carrying out by simple operation and adaptable to large scale commercial production.

Process for the production of 1α-hydroxy provitamin D3 and 1α-hydroxy vitamin D3

A process for the production of 1α-hydroxy provitamin D3 which comprises treating 1α, 2α-epoxy-cholesta-4,6-diene-3-one at a low temperature with liquid ammonia; with ammonium chloride and with lithium metal to produce 1α,3β-dihydroxycholest-6-ene, converting this to the corresponding 1α,3β-di(lower alkanoyl) derivative, reacting the latter with bromine to give 1α,3β-di(lower alkanoyloxy) 6β,7α-dibromocholestane, which is dehydrobrominated to give 1α,3β-di(lower alkanoyloxy)-cholesta-5,7-diene, which is converted to the desired provitamin. The 1α,3β-di(lower alkanoyloxy)cholest-6-ene can be oxidized to the corresponding 5-ene-7-one, which is converted to the 7-p-toluenesulfonyl hydrazone derivative, which is converted to the 1α-hydroxy provitamin D3 di(lower alkanoyloxy) derivative or to the 1α-hydroxy provitamin D3. Novel compounds are 1α,3β-dihydroxy-cholest-6-ene, its di(lower alkanoyloxy) derivative; 1α,3β-di(lower alkanoyloxy)-6β,7α-dibromocholestane; 1α,3β-diacetoxycholest-5-ene-7-one and the corresponding 7-p-toluenesulfonylhydrazone derivative.