| 摘要 |
<p>An improved process for the preparation of 7-substituted amino-1-cyclopropyl-6,8-difluoro-1,4-dihydro-4-oxo-3-quinolinecarboxylic acids is described where an alkyl ester of a 6,7,8-trifluoro precursor is converted to a trialkylsilyl ester which fluorine at C7 is directly displaced to the desired product.</p> |
