Opening of the Macrocyclic Ring in 5,10:8,9‐Disecosteroids ( = Steroklastanes)(Article)
- aFaculty of Chemistry, University of Belgrade, Studentski trg 16, P.O. Box 550, Belgrade, YU-11001
- bInstitute of Chemistry, Technology and Metallurgy, Belgrade, YU-11001
- cCentral Function Research, Ciba- Geigy Ltd., Basel, CH-4002, Switzerland
- dResearch Laboratories, Pharmaceuticals Division, Ciba- Geigy Ltd., Basel, CH-4002, Switzerland
Abstract
Catalytic hydrogenation of the Δ3‐unsaturated (9R,10 R)‐ and (9S,10 S)‐epoxyenol lactones 3a, b., and 4a, b., respectively, affords, in addition to the expected saturated epoxylactones 5a, b and 7a, b, also open‐chain products, i.e. the diastereoisomeric (9R,10R)‐ and (9S,10S)‐9,10‐expoxy‐8‐oxo‐4,5‐secosteroklastan‐5‐oic acids 6a, b. and 8a, b. Alkaline hydrolysis of the lactone ring of compounds 5 and 7 and subsequent acetylation of the corresponding hydroxy derivatives give as the major products the open‐chain, diasteroisomeric (9R,10R)‐ and (9S,10S)‐4‐acetoxy‐9,10‐epoxy‐methyl esters 9a, b and 11a, b, respectively, and, but only in the androstane series, the tetrahydropyran derivatives 10a and 12a, as the minor components. Copyright © 1992 Verlag GmbH & Co. KGaA, Weinheim
Indexed keywords
| EMTREE drug terms: | steroid |
|---|---|
| EMTREE medical terms: | articlechemical analysishydrolysis |
- ISSN: 0018019X
- Source Type: Journal
- Original language: English
- DOI: 10.1002/hlca.19920750118
- Document Type: Article
Kalvoda, J.; Research Laboratories, Pharmaceuticals Division, Ciba‐Geigy Ltd., Switzerland
© Copyright 2016 Elsevier B.V., All rights reserved.
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