| 摘要 |
PURPOSE:To obtain the subject compound useful as an antimicrobial or its synthetic intermediate thereof in high yield by condensing a 6- fluoroquinolonecarboxylic acid derivative with a saturated heterocyclic amine and a boric ester under heating. CONSTITUTION:A compound of formula I (R1 is lower alkyl or lower cycloalkyl; R2 is H, halogen or lower alkoxy; R3 is arbitrary functional residue capable of participating in nucleophilic substitution reaction) is condensed with a compound of formula II [X is CH2, NR4 (R4 is H or lower alkyl) or O; Y is NH2 to be bonded to carbon atom on saturated heterocyclic ring, lower alkylamino or group readily convertible to the amino group by a chemical means; (n) is 0 or 1] and a compound of formula III (R5 is lower alkyl, aryl which may be substituted or substituted aralkyl) such as trimethoxyboran under heating in a solventless state or in the presence of a solvent to give a 6-fluoro-7- substituted quinolonecarboxylic acid derivative of formula IV. |
