A process for producing a 6-fluoro-7-substituted quinolonecarboxylic acid derivative represented by general formula (4) (wherein R₁ represents alkyl; R₂ represents hydrogen, halogen or alkoxy; X represents -CH₂-, -NR₄- or -O-; R₄ represents hydrogen or alkyl; Y represents hydrogen, amino or alkylamino; and n represents 0 or 1), characterized by conducting thermal condensation of a 6-fluoroquinolonecarboxylic acid derivative represented by general formula (1) (wherein R₁ and R₂ are as defined above; and R₃ represents a group capable of nucleophilic substitution), with a substituted saturated heterocyclic amine represented by general formula (2) (wherein X, Y and n are as defined above; and R₄ represents hydrogen or alkyl), in the presence of an alkyl borate represented by the general formula (3): B(OR₅)₃ wherein R₅ represents alkyl, etc.
一种生产通式(4)代表的6-
氟-7-取代
喹啉羧酸衍
生物的工艺(其中R₁代表烷基;R₂代表氢、卤素或烷氧基;X代表-CH₂-、-NR₄-或-O-;R₄代表氢或烷基;Y代表氢、
氨基或烷基
氨基;和 n 代表 0 或 1),其特征在于对通式(1)代表的
6-氟喹啉酮羧酸衍
生物进行热缩合(其中 R₁ 和 R₂ 如上定义;和 R₃ 代表能够亲核取代的基团),与通式(2)代表的取代饱和杂环胺(其中 X、Y 和 n 如上定义;R₄ 代表氢或烷基),在通式(3)代表的烷基
硼酸盐存在下:B(OR₅)₃ 其中 R₅ 代表烷基等。