| 摘要 |
A method for producing a 6alpha-fluorinated corticosteroid or derivative thereof by reacting a 17-hydroxy-21-ester epoxide of Formula II with a stereoselective fluorinating agent to stereoselectively form a 21-ester-17-hydroxy 6alpha-fluorinated compound of Formula VII R<SUP>1 </SUP>can be OC(O)-R<SUB>d</SUB>; R<SUP>4 </SUP>can be C(O)-R<SUB>d</SUB>; R<SUP>3 </SUP>can be H or R<SUB>d</SUB>. Each R<SUB>d </SUB>may be the same or different and is independently selected from (C<SUB>1-4</SUB>)alkyl, aryl and heteroaryl. The dashed line can be a single or a double bond. R<SUP>4 </SUP>may be, for example, acetyl; R<SUP>3 </SUP>may be, for example, alpha or beta methyl; R<SUP>1 </SUP>may 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(R).
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