83872-45-1

Upstream product

• 10162-98-8 (20S)-20-methyl-pregnene-(5)-diol-(3β.21) 
• 98-59-9 p-toluenesulfonyl chloride 
• 40736-33-2 (20S)-20-hydroxymethylpregn-4-en-3-one 
• 19707-16-5 22-tosyloxy-23,24-dinorchol-4-en-3-one 
• 1474-14-2 3β-acetoxybisnor-5-cholenic acid 
• 145573-34-8 (20S)-20-(p-Toluolsulfonyloxymethyl)pregna-1,5-dien-3-on 
• 51231-24-4 (20S)-(6β-Methoxy-20-methyl-3α,5-cyclo-5α-pregnan-21-ol)-p-toluolsulfonat 

Downstream Products

• 58507-66-7 (20S)-(20-Methyl-3β-<(tetrahydropyran-2-yl)oxy>-5-pregnen-21-ol)-p-toluolsulfonat 
• 1042-59-7 20-methylpregn-5-en-3β-ol 
• 7494-34-0 27-nor-5-cholesten-3β-ol-25-one 
• 38388-19-1 20-Methylpregn-4-en-3-on 
• 5737-19-9 20-Methyl-5α-pregnan 
• 102848-92-0 20-Methyl-5α-pregnan-3-on 
• 57-88-5 cholesterol 

Relevant academic research and scientific papers

Methods for preparing cholesterol, and derivatives and analogs thereof

The present invention relates to the field of pharmaceutical chemistry, and in particular to methods of preparing cholesterol,and derivatives and analogs thereof. The cholesterol derivatives include, but not limited to, 7-dehydrocholesterol, 25-hydroxycholesterol, 25- hydroxy7dehydrocholesterol and ergosterol. In the invention, phytosterol can be used as a raw material to prepare the compound shown in the formula I through microbial conversion, and then cholesterol and the derivatives and analogues thereof are prepared.

Transformation of (20S)-20-(hydroxymethyl)pregna-1,4-dien-3-one into (20S)-20-(p-toluene-sulfonyloxymethyl)pregna-1,5-dien-3β-ol and -3α-ol: Intermediates of vitamin D derivatives

Efficient three-step approaches to the two 3-epimeric 22-tosylated 1,5-diene-3,22-diols 6 and 7 starting with (20S)-20-(hydroxymethyl)pregna-1,4-dien-3-one (1) were developed and optimized. Isomerization of 1 to the 1,5-dien-3-one 3 and subsequent tosylation furnished the deconjugated 3-ketone 4. The 3β-alcohol 6 was available from 4 by means of in situ generated calcium borohydride. Treatment of 4 with lithium trisiamylborohydride (LS-Selectride) afforded the highest yield of the hitherto unknown 3α-epimer 7. Following the optimized synthesis, 6 and 7 were obtained from 1 in 60 % and 50 % overall yield, respectively.