[F:1][C:2]1[C:11]([CH3:12])=[C:10]2[C:5]([C:6](=[O:22])[C:7]([C:17]([O:19]CC)=[O:18])=[CH:8][N:9]2[C@@H:13]2[CH2:15][C@@H:14]2[F:16])=[CH:4][CH:3]=1.Cl>C(O)(=O)C>[F:1][C:2]1[C:11]([CH3:12])=[C:10]2[C:5]([C:6](=[O:22])[C:7]([C:17]([OH:19])=[O:18])=[CH:8][N:9]2[C@@H:13]2[CH2:15][C@@H:14]2[F:16])=[CH:4][CH:3]=1Ethyl 7-fluoro-1-[2-(S)-fluoro-1-(R)-cyclopropyl]-1,4-dihydro-8-methyl-4-oxoquinoline-3-carboxylate (1.40 g, 4.56 mmol) was dissolved in acetic acid (4 ml), and after adding concentrated hydrochloric acid (4 ml) thereto, it was heated under reflux for 3 hours. After cooling, the reaction solution was poured into ice water (50 ml) and the precipitated crystals were filtered out. After washing the filtered-out crystals with an excess amount of water, washing in cold ethanol and washing in diethyl ether were performed in that order, and after drying under a reduced pressure, 1.18 g (93%) of the title compound was obtained in the form of a white powder.
Wird geladen…
