title: Convenient synthesis of 18-hydroxylated cortisol and prednisolone.
abstract: 18,20-Epoxy-11 beta,17 alpha,20 beta,21-tetrahydroxypregn-4-en-3-one was synthesized by the application of hypoiodite reaction to the cortisol acetonide. The intermediary 18-iodo derivative was converted to the 11-oxo steroid by chromic acid prior to silver ion-assisted solvolysis. Removal of the protective group with hydrochloric acid was finally carried out to give the desired 11 beta,17 alpha,18,21-tetrahydroxypregn-4-ene-3,20-dione as the hemiacetal form. 18,20-Epoxy-11 beta-17 alpha,20 beta,21- tetrahydroxypregna-1,4-dien-3-one was also prepared from prednisolone through a similar reaction sequence.
authors.affiliation: Faculty of Pharmaceutical Sciences, Higashi-Nippon-Gakuen University, Hokkaido, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Kurosawa
authors.forename: S
authors.initials: S
authors.lastname: Ikegawa
authors.forename: H
authors.initials: H
authors.lastname: Chiba
authors.forename: Y
authors.initials: Y
authors.lastname: Ito
authors.forename: S
authors.initials: S
authors.lastname: Nakagawa
authors.forename: K
authors.initials: K
authors.lastname: Kobayashi
authors.forename: M
authors.initials: M
authors.lastname: Tohma
mesh_terms: D006854:Hydrocortisone / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D007454:Iodides; D015394:Molecular Structure; D010084:Oxidation-Reduction; D011239:Prednisolone / Q000031:analogs & derivatives* / Q000138:chemical synthesis; D012834:Silver; D018030:Silver Compounds
chemical_list: C078536:18-hydroxyprednisolone; D007454:Iodides; D018030:Silver Compounds; D012834:Silver; C030584:silver iodide; D011239:Prednisolone; C033689:18-hydroxycortisol; D006854:Hydrocortisone