Method for the preparation of 6α-fluoro corticosteroids

Details Method for the preparation of 6α-fluoro corticosteroids Method for the preparation of 6α-fluoro corticosteroids

2006-08-29

2006-08-29

Coleman, Brenda (Department: 1624)

Organic compounds -- part of the class 532-570 series

Organic compounds

Heterocyclic carbon compounds containing a hetero ring...

C552S569000, C552S570000, C552S573000, C552S574000

Reexamination Certificate

active

07098328

ABSTRACT:
A method for producing a 6α-fluorinated corticosteroid or derivative thereof by reacting a 17-hydroxy-21-ester epoxide of Formula IIwith a stereoselective fluorinating agent to stereoselectively form a 21-ester-17-hydroxy 6α-fluorinated compound of Formula VIIR1can be OC(O)—Rd; R4can be C(O)—Rd; R3can be H or Rd. Each Rdmay be the same or different and is independently selected from (C1-4)alkyl, aryl and heteroaryl. The dashed line can be a single or a double bond. R4may be, for example, acetyl; R3may be, for example, alpha or beta methyl; R1may be, for example, acetate or propionate. The stereoselective fluorinating agent used in the reaction may be, for example, a fluoropyridinium or fluoroquinuclidium compound, for example, Selectfluor®.

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