1-Methylpiperazine → 1-Cyclopropyl-6-fluoro-8-methoxy-7-(4-methyl-1-piperazinyl)-1,4-dihydro-4-oxoquinoline-3-carboxylic acid

HRID 358861Notes

Reaction equation

[CH3:1][N:2]1[CH2:7][CH2:6][NH:5][CH2:4][CH2:3]1.[CH:8]1([N:11]2[C:20]3[C:15](=[CH:16][C:17]([F:24])=[C:18](F)[C:19]=3[O:21][CH3:22])[C:14](=[O:25])[C:13]([C:26]([OH:28])=[O:27])=[CH:12]2)[CH2:10][CH2:9]1>CS(C)=O>[CH:8]1([N:11]2[C:20]3[C:15](=[CH:16][C:17]([F:24])=[C:18]([N:5]4[CH2:6][CH2:7][N:2]([CH3:1])[CH2:3][CH2:4]4)[C:19]=3[O:21][CH3:22])[C:14](=[O:25])[C:13]([C:26]([OH:28])=[O:27])=[CH:12]2)[CH2:10][CH2:9]1

Participants

Conditions

Temperature: 70 °C

Procedure

0.12 g (0.0012 mole) of N-methylpiperazine was added to a solution of 0.09 g (0.0003 mole) of 1-cyclopropyl-6,7-difluoro-8-methoxy-1,4-dihydro-4-oxoquinoline-3-carboxylic acid (IIc) (prepared as described in Preparation 6) in 0.5 ml of dimethyl sulfoxide, and the mixture was stirred at 70° C. for 6 hours. At the end of this time, the solvent and the excess N-methylpiperazine were removed by evaporation under reduced pressure at the same temperature, and the residue was washed with ethyl acetate and subjected to silica gel column chromatography, eluted with methanol, to afford 0.03 g of 1-cyclopropyl-6-fluoro-8-methoxy-7-(4-methyl-1-piperazinyl)-1,4-dihydro-4-oxoquinoline-3-carboxylic acid as colorless powdery crystals, melting at 211°-214° C.

Workup

customAt the end of this time, the solvent and the excess N-methylpiperazine were removed by evaporation under reduced pressure at the same temperature
washthe residue was washed with ethyl acetate
washeluted with methanol

Sources & evidence

ORD record: ord-dc86e9022bf84fd284bba053d3080fcf
Source dataset: uspto-grants-1991_03
DOI: 10.6084/m9.figshare.5104873.v1
Patent number: US04997943

Reaction notes

Loading…