反应详情

6.6 g (0.02 mole) of 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinolinecarboxylic acid are heated at 80° C. with 4.5 g of methyl 2-chloroacetoacetate and 4.2 g of triethylamine in 100 ml of dimethylformamide for 3 hours. The solution is then concentrated in vacuo, the residue is stirred with 50 ml of water and the resulting solid product is washed with methanol and water and recrystallized from glycol monomethyl ether. 3.9 g (44% of theory) of 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-{4-[2-oxo-1-(methoxycarbonyl)-1-propyl]-1-piperazinyl}-3-quinolinecarboxylic acid of decomposition point 224° to 228° C. are isolated.

1. concentrationThe solution is then concentrated in vacuo
2. washthe resulting solid product is washed with methanol and water
3. customrecrystallized from glycol monomethyl ether