| 摘要 |
PROBLEM TO BE SOLVED: To obtain a new compound having a quinolone skeleton and useful as a medicine, especially an antibacterial agent. SOLUTION: A quinolone carboxylic acid derivative of formula I (R is H or a lower alkyl; R1 R2 are each H or a lower alkyl; X is nitro or amino) and its salt and its hydrate, preferably 6-amino-1-cyclopropyl-1,4-dihydro-8- methoxy-7-(3-methyl-1-piperazinyl)-4-oxo-3 quinoline carboxylic acid, or the like. The compound of formula I is obtained by reacting a quinolone carboxylic acid derivative of formula II (R' is a lower alkyl) with sodium methoxide in a solvent such as methanol at a reaction temperature of from the refluxing boiling point of the reaction solution to 150 deg.C, hydrolyzing the reaction product in the presence of an alkali such as sodium hydroxide at a reaction temperature of from room temperature to the boiling point of the solvent, and, if necessary, catalytically reducing the hydrolysis product in the presence of palladium-carbon catalyst in a solvent such as dimethylformamide at room temperature.
|
