INDUSTRIAL PRODUCTION OF QUINOLONE-CARBOXYLIC ACID AND ITS SYNTHETIC INTERMEDIATE

摘要

PROBLEM TO BE SOLVED: To industrially advantageously obtain the subject compound useful as an antibacterial agent by reacting a specific 3-aminopyrrolidine with an aldehyde or a ketone to obtain a Schiff's base, temporarily protecting, condens ing with a quinolone skeleton and deprotecting. SOLUTION: The objective quinolone-carboxylic acid derivative expressed by formula V and useful as an antibacterial agent is readily obtained in high purity and a high yield by condensing 3-aminomethyl-3-fluoromethylpyrrolidine of formula I, its R-isomer or its S-isomer with an aldehyde or a ketone of formula II [R<1> and R<2> are each H, an alkyl or a (substituted) aryl], temporarily protecting amino group as a Schiff's base to obtain a compound of formula III, condensing the compound, its R-isomer or its S-isomer with a compound having a quinolone skeleton of formula IV [R<3> is F or a (halogen-substituted) acyloxy; R<4> is a halogen or methoxy; Hal is a halogen] and deprotecting.