title: A novel synthetic approach to (20R)- and (20S)-21-hydroxy steroids. Synthesis of a marine sterol 21-hydroxycholesterol.
abstract: A short and efficient synthesis of steroid synthons, di(tert-butyldimethylsilyl) ethers of 3,21-dihydroxy-24-nor-chol-5-en-23-al (8 and 10) and of ethyl 3,21-dihydroxy-25-homo-chola-5,23-dien-25-oate (9 and 11), having natural (20R) and unnatural (20S) configuration from 3β-(tert-butyldimethylsilyloxy)-14α,20ξ-card-5-enolide (2) is reported. Further elongation of the side chain of these synthons provides a new method for the synthesis of (20R) and (20S)-21-hydroxy steroids. The utility of the method was exemplified by the synthesis of a natural marine sterol - 21-hydroxycholesterol (18).
authors.affiliation: Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland.
authors.forename: Hanna
authors.initials: H
authors.lastname: Koenig
authors.forename: Iwona
authors.initials: I
authors.lastname: Skiera
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Błaszczyk
authors.forename: Zdzisław
authors.initials: Z
authors.lastname: Paryzek
mesh_terms: D001688:Biological Products / Q000138:chemical synthesis; D006888:Hydroxycholesterols / Q000138:chemical synthesis*; D006914:Hydroxysteroids / Q000138:chemical synthesis*; D008386:Marine Biology
chemical_list: D001688:Biological Products; D006888:Hydroxycholesterols; D006914:Hydroxysteroids