474432-41-2

Upstream product

• 100858-27-3 (S)-(Z)-{2-[5-(tert-butyldimethylsiloxy)-2-methylenecyclohexylidene]ethyl}diphenylphosphine oxide 
• 474432-39-8 (24R)-de-A,B-24,25-dihydroxycholestan-8-one cyclic 24,25-(1-methylethylidene acetal) 
• 226569-00-2 (1R,3aR,4S,7aR)-1-[(1R,4R)-4,5-dihydroxy-1,5-dimethylhexyl]-7a-methyl-octahydro-1H-inden-4-ol 
• 239100-24-4 (8β,24R)-de-A,B-cholesta-8,24,25-triol cyclic 24,25-(1-methylethylidene acetal) 

Downstream Products

• 55721-11-4 24(R),25-dihydroxycholecalciferol 

Relevant academic research and scientific papers

Stereoselective convergent synthesis of 24,25-dihydroxyvitamin D3 metabolites: a practical approach.

Vitamin D3 active metabolites 24R,25-(OH)2-D3, 24S,25-(OH)2-D3, and 1 alpha, 24R,25-(OH)3-D3 were synthesized by a convergent and stereoselective approach. In the synthetic route, the stereogenic center at C-24 was generated through ultrasonically induced aqueous conjugate addition of iodide 6 to Seebach's dioxolanone 5, and the vitamin D triene system was constructed using the Lythgoe approach. The synthesis, which is both short (seven steps from iodide 6) and efficient (32-40% overall yield), allows the preparation of large quantities of the metabolites and provides a novel example of a highly stereoselective reaction promoted by the zinc-copper couple in aqueous media.

Chemical Synthesis of Side-Chain-Hydroxylated Vitamin D3 Derivatives and Their Metabolism by CYP27B1

1α,25-Dihydroxyvitamin D3 (abbreviated here as 1,25D3) is a hormonally active form of vitamin D3 (D3), and is produced from D3 by CYP27 A1-mediated hydroxylation at C25, followed by CYP27B1-mediated hydroxylation at C1. Further hydroxylation of 25D3 and 1,25D3 occurs at C23, C24 and C26 to generate corresponding metabolites, except for 1,25R,26D3. Since the capability of CYP27B1 to hydroxylate C1 of side-chain-hydroxylated metabolites other than 23S,25D3 and 24R,25D3 has not been examined, we have here explored the role of CYP27B1 in the C1 hydroxylation of a series of side-chain-hydroxylated D3 derivatives. We found that CYP27B1 hydroxylates the R diastereomers of 24,25D3 and 25,26D3 more effectively than the S diastereomers, but shows almost no activity towards either diastereomer of 23,25D3. This is the first report to show that CYP27B1 metabolizes 25,26D3 to the corresponding 1α-hydroxylated derivative, 1,25,26D3. It will be interesting to examine the physiological relevance of this finding.