ISSN:
0075-4617
Keywords:
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Preparation of 6α-Fluoro-11β, 21 -dihydroxy-l6α-methyl-l,4-pregnadiene-3,20-dione (Fluocortolone) via Substrate-Structure- Directed Specific 11β- Hydroxylation by Curvularia lunataThe formation of the by-products 14 and 13, with 9α- and 14α-hydroxy groups, in the 11β-hydroxylation of 6α-fluoro-21-hydroxy-16α-methyl-4-pregnene-3,20-dione (9b) with Curvularia lunata is inhibited by using a similar substrate with 5α-bromo-substituent by sterical shielding of the α-side. A subsequent route for the synthesis of 6α-fluoro-11β,21-dihydroxy-16α-methyl-1,4-pregnadiene-3,20-dione (15) is described.
Notes:
Die bei der 11β-Hydroxylierung von 6α-Fluor-21-hydroxy-16α-methyl-4-pregnen-3.20-dion (9b) mit Curvularia lunata entstehenden Nebenprodukte 14 und 13 mit 9α- und 14α-Hydroxy-Funktion treten bei Einsatz der 5α-Brom-substituierten Vorstufe 5 durch sterische Abschirmung der α-Seite nicht auf. Der weitere Synthesegang zu 6α-Fluor-11β.21-dihydroxy-16α-methyl-1.4-pregnadien-3.20-dion (15, Fluocortolon) wird beschrieben.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.19697260124