Formaldehyde → 8-(3,4-Dimethyl-1-piperazinyl)-1-ethyl-7-fluoro-4-oxo-1,4-dihydro-benzo[b][1,8]naphthyridine-3-carboxylic acid
反応式
[CH2:1]([N:3]1[C:12]2[N:11]=[C:10]3[CH:13]=[C:14]([N:18]4[CH2:23][CH2:22][NH:21][CH:20]([CH3:24])[CH2:19]4)[C:15]([F:17])=[CH:16][C:9]3=[CH:8][C:7]=2[C:6](=[O:25])[C:5]([C:26]([OH:28])=[O:27])=[CH:4]1)[CH3:2].[CH2:29]=O>C(O)=O>[CH3:24][CH:20]1[N:21]([CH3:29])[CH2:22][CH2:23][N:18]([C:14]2[C:15]([F:17])=[CH:16][C:9]3[C:10]([CH:13]=2)=[N:11][C:12]2[N:3]([CH2:1][CH3:2])[CH:4]=[C:5]([C:26]([OH:28])=[O:27])[C:6](=[O:25])[C:7]=2[CH:8]=3)[CH2:19]1参加物
4
実験手順
8-(3,4-Dimethyl-1-piperazinyl)-1-ethyl-7-fluoro-4-oxo-1,4-dihydro-benzo[b][1,8]naphthyridine-3-carboxylic acid is prepared under the conditions of Reference Example 21 but starting from 2.3 g of 1-ethyl-7-fluoro-8-(3-methyl-1-piperazinyl)-4-oxo-1,4-dihydro-benzo[b][1,8]naphthyridine-3-carboxylic acid, 2.26 cm3 of 98% formic acid and 5.6 cm3 of a 30% aqueous solution of formaldehyde. 1.75 g of 8-(3,4-dimethyl-1-piperazinyl)-1-ethyl-7-fluoro-4-oxo-1,4-dihydro-benzo[b][1,8]naphthyridine-3-carboxylic acid are obtained in the form of a yellow solid melting at 293°-294° C.