| 摘要 |
A process for preparing oxazoline corticosteroid intermediates of formula (V) wherein R<1> represents hydrogene (H), loweralkyl, phenyl or phenylalkyl; R<4> represents H or loweralkyl, preferably methyl having either the alpha or beta stereochemistry; and R<9> represents hydrogen, fluoro, chloro or loweralkyl. The process comprises contacting a compound of formula (III) herein, with (A) Vilsmeier reagent, followed by acid hydrolysis to yield the compound of formula (V); or alternatively, (B) an acid having a pKa of less than 5, to yield the compound of formula (V). |
