Acetone Fluocinonide

A solution of 50 mg of 6a-fluoro-triamcinolone acetonide in 1 ml of pyridine and 1 ml of acetic anhydride is allowed to stand at room temperature for 18 hours. Removal of the reagents in vacuo gives a crystalline residue which after crystallization from acetone-hexane gives the pure 16a,17a-isopropylidene 6o -fluoro-triamcinolone 21 acetate (fluocinonide), as described in U.S. Patent 3,197,469. 

Fluocinonide. 21-(Acetyloxy)-6a.9-difluoro- (10-hydroxy-l6ct,l 7-f( J -methylethylidene ibi (0Xy)]pregna l, 4 dienc-3.20-dione 9-difIuoro l 10,16a,l 7 2l-teirahydr oxypregna-l,4-diene-3,20-dione, cyclic 16,17-acetal with acetone, 2l-acetate 21 -acetoxy-6a.9a-difluoro-l 10-hydr-oxy -16a, ] 7a -isopropyl idenedi oxy - ( 4 -pregnadiene -3 20 -... 

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