5-Benzylamino-1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid → 7-(4-Acetyl-3-methyl-1-piperazinyl)-5-benzylamino-1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid

Participants

Reaction Steps

A mixture of 5-benzylamino-1-cyclopropyl-6,7-difluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid, 1-acetyl-2-methylpiperazine and pyridine was heated under reflux. The reaction mixture was concentrated under reduced pressure, and water was added to the residue. The mixture was extracted with chloroform. The extract was dried and chloroform was evaporated. Ethanol was added to the residue, and the crystals were collected by filtration to give 7-(4-acetyl-3-methyl-1-piperazinyl)-5-benzylamino-1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid. It was recrystallized from ethanol/diisopropyl ether. m.p. 235°-236° C.

Provenance & Evidence