262594-22-9Relevant articles and documents
6-s-cis locked analogues of the steroid hormone 1α,25-dihydroxyvitamin D3. Synthesis of novel A-ring stereoisomeric 1,25-dihydroxy-3-epi-19-nor-previtamin D3 derivatives
Diaz, Monica,Ferrero, Miguel,Fernandez, Susana,Gotor, Vicente
, p. 5647 - 5652 (2000)
Efficient syntheses of A-ring synthons 24 and 32 are described from hydroxy ester 16, which is easily available on a preparative scale from (-)-quinic acid. Key features of the syntheses were (a) the ability to selectively perform desilylations in the presence of p-nitrobenzoate esters and (b) the excellent yield and complete stereospecificity with which the configuration of alcohols 16, 18, and 26 could be inverted under Mitsunobu conditions. Thus, A-ring synthons 24 and 32 were both prepared in 35-38% yield (eight steps) from the common precursor 16. The coupling of A-ring synthons 24 and 32 with the appropriate CD-ring/side chain fragment 7 provides access to novel 6-s-cis locked analogues of steroid hormone 1α,25-dihydroxyvitamin D3: 1α,25-dihydroxy-3-epi-19-nor-previtamin D3 (37) and 1β,25-dihydroxy-3-epi-19-nor-previtamin D3 (38), which are unable to undergo rearrangement to the respective vitamin D form by virtue of the absence of the C-19 methyl group. Compounds 37 and 38 can be used as tools for studying the genomic and nongenomic mechanisms of action of the previtamin form of the hormone 1α,25-dihydroxyvitamin D3.
Synthesis of two 6-s-cis locked stereoisomeric analogues of the steroid hormone 1α,25-dihydroxyvitamin D3: 1 α,25-dihydroxy-19-nor-previtamin D3 and 1β,25-dihydroxy- 19-nor-previtamin D3
Díaz, Mónica,Ferrero, Miguel,Fernández, Susana,Gotor, Vicente
, p. 775 - 779 (2007/10/03)
An efficient synthesis of A-ring precursors 8 and 9 from inexpensive commercially available (-)-quinic acid has been developed. A-Ring synthon 8 has been obtained through a short sequence (eight steps) in high overall yield (30%). One key step in the synt
