Formaldehyde → 1-Cyclopropyl-8-(3,4-dimethyl-1-piperazinyl)-7-fluoro-4-oxo-1,4-dihydro-benzo[b][1,8]naphthyridine-3-carboxylic acid
Reaction equation
[CH:1]1([N:4]2[C:13]3[N:12]=[C:11]4[CH:14]=[C:15]([N:19]5[CH2:24][CH2:23][NH:22][CH:21]([CH3:25])[CH2:20]5)[C:16]([F:18])=[CH:17][C:10]4=[CH:9][C:8]=3[C:7](=[O:26])[C:6]([C:27]([OH:29])=[O:28])=[CH:5]2)[CH2:3][CH2:2]1.[CH2:30]=O>C(O)=O>[CH:1]1([N:4]2[C:13]3[N:12]=[C:11]4[CH:14]=[C:15]([N:19]5[CH2:24][CH2:23][N:22]([CH3:30])[CH:21]([CH3:25])[CH2:20]5)[C:16]([F:18])=[CH:17][C:10]4=[CH:9][C:8]=3[C:7](=[O:26])[C:6]([C:27]([OH:29])=[O:28])=[CH:5]2)[CH2:2][CH2:3]1Participants
4
Reactant 2
Product 1
Reagents, catalysts & solvents 1
Procedure
1-Cyclopropyl-8-(3,4-dimethyl-1-piperazinyl)- 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 1.9 g of 1-cyclopropyl-7-fluoro-8-(3-methyl-1-piperazinyl)-4-oxo-1,4-dihydro-benzo[b][1,8]naphthyridine-3-carboxylic acid, 1.38 cm3 of formic acid and 3.30 cm3 of a 30% aqueous solution of formaldehyde. After recrystallizing crude product from 50 cm3 of ethanol, 1.3 g of 1the cyclopropyl-8-(3,4-dimethyl-1-piperazinyl)-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 219° C.