[N+]([O-])(O)=[O:2].[CH:5]1([N:8]2[C:17]3[C:12](=[CH:13][C:14]([F:24])=[C:15](N4CCNCC4)[N:16]=3)[C:11](=[O:25])[C:10]([C:26]([OH:28])=[O:27])=[CH:9]2)[CH2:7][CH2:6]1>S(=O)(=O)(O)O>[CH:5]1([N:8]2[C:17]3[C:12](=[CH:13][C:14]([F:24])=[C:15]([OH:2])[N:16]=3)[C:11](=[O:25])[C:10]([C:26]([OH:28])=[O:27])=[CH:9]2)[CH2:7][CH2:6]1To a solution of 2 ml of 70% nitric acid in 10 ml of 98% sulfuric acid was added in portions 1.0g (3.0 mmole) of 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-1,8-naphthyridine-3-carboxylic acid, keeping the temperature between 25°-30° C. The resulting solution was stirred at room temperature for 18 hours and poured onto 40 g of ice. The mixture was stirred at room temperature for 24 hours, concentrated in vacuo, the pH adjusted to 12 with aqueous sodium hydroxide, and filtered through a fiber glass pad. The filtrate was acidified to pH 3.5 with 6.0M hydrochloric acid, the resulting precipitate removed by filtration, washed with water then ether and dried in vacuo to give 0.23 g of the title compound, mp 325°-327° C.
Wird geladen…