9a-Fluoroprednisolone

I60C-Hydroxy Derivatives of Gorticoids and their Acetonides. The preparation of 16a-hydroxy-9a-fluoroprednisolone (48) from the 3,20-bisethylene ketal of hydrocortisone acetate (49) has been reported (73). The latter was dehydrated with thionyl chloride in pyridine to yield the 4,9(11),16-triene (50). The 16,17-unsaturated linkage was selectively hydroxylated with OsO /pyridine to yield the 16a,17a-diol (51), which was converted... 

Flucinolone Acetonide Fludrocortisone Acetate Fludroxycortide Flumethasone Fluocortolone Fluorometholone 9a-Fluoroprednisolone Acetate... 

Methylation of hydrocortisone/prednisolone in positions C-4, C-7, C-12, and C-21 failed to give useful products. Methylation at C-16, in contrast, led to 16a- and 16p-methyl-9a-fluoroprednisolones which were exceptionally useful. Both series were prepared using 3a-acetoxy-5a-pregn-16-ene-ll,20-dione derived from desoxycholic acid (80). A much shorter route was subsequently developed from... 

In 1973 D-homo corticosteroids (109—112), eg, D-homo-9a-fluoroprednisolone acetate (111) were reported to have antiinflammatory activity (107). Compounds such as 21-acetoxy-llp-fluoro-9a-chloro-17aa-hydroxy-D-homo-pregn-4-en-3,20-dione (110) had especially strong topical activity with weak systemic activity (108). Other preparations of D-homocorticoids included... 

G. Cavina, L. Valvo, B. Gallinella, R. Porra, and A. L. Savella, The identification of related substances in 9a-fluoroprednisolone-21 acetate by means of high-performance liquid chromatography with diode array detector and mass spectrometry, J. Pharm. Biomed. Anal., 79 437(1992). 

Triamcinolone is 9a-Fluoro-lip,16a,17,21-tetrahydroxypregna-1,4-diene-3,2O-dione. It is also known as A -9a-fluoro-16a-hydroxyhydrocorti-sone 9a-fluoro-16a-hydroxyprednisolone A -16a-hydroxy-9a-fluorohydrocortisone and 16a-hydroxy-9a-fluoroprednisolone. 

Common Name 16-methylene-9a-fluoroprednisolone 21-acetate Structural Formula ... 

Dexamethasone (I) is 9a-fluoro-llS,17a,21-trihy-droxy-16a-methylpregna-l,4-dlene-3,20-dione. Other names for Che compound Include 9a-fluoro-16a-methylprednisolone and 16a-methyl-9a-fluoroprednisolone. The Merck Index lists three other chemical names for dexamethasone. Proprietary names for dexamethasone include Decadron, Dexacortisyl, Oradexon, Hexadrol and Deronll. A number of others are listed in the monograph for dexamethasone in the Merck Index. ... 

Many synthetic corticoids were introduced following the discovery of triamcinolone. These include triamcinolone 16,17-acetonide, 6o -methylprednisolone, 16a -methyl-9o -fluoroprednisolone (dexamethasone), 16 -methyl-9a(-fluoroprednisolone (betamethasone), 6o -fluoro-16a-methylprednisolone (paramethasone), 16-methylene-prednisolone, and 6a, 9a -dlfluoro-16a-hydroxyprednisolone 16,17-acetonide (fluocino-lone acetonide). Microbiology played no essential role in their discovery, although in some cases microbiological technology has been employed to advantage in their manufacture. 

Methylenesteroids. Trifluoroacetic acid in benzene added during 5 min. at 10° to a stirred soln. of 9a-fluoro-16a,17a-oxido-16j5-methyl-l,4-pregnadiene-lly ,21-diol-3,20-dione 21-acetate in the same solvent, and kept 18 hrs. at 25° 16-methylene-9a-fluoroprednisolone 21-acetate. Y 80. D. Taub, R. D. Hoff-sommer, and N. L. Wendler, J. Org. Ghem. 29, 3486 (1964). 

Highly active derivatives can be derived from prednisolone by introducing halogens, mainly fluorine, at positions 9 and 6, methyl groups at 6 and 16, a hydroxyl group at 16, etc. For instance, dexametha-sone and betamethasone are the 16a- and jS-methyl derivatives of 9a-fluoroprednisolone, respectively, and triamcinolone is the 16a-hydroxy derivative of 9a-fluoroprednisolone. 

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