Piperazine → 7-(1-Piperazinyl)-1-cyclopropyl-6-fluoro-8-methyl-1,4-dihydro-4-oxoquinoline-3-carboxylic acid

Participants

Reaction Steps

A mixture of 1-cyclopropyl-6,7-difluoro-1,4-dihydro-8-methyl-4-oxo-3-quinolinecarboxylic acid (200 mg), piperazine (250 mg) in anhydrous DMSO (2 ml) was stirred at 70° to 80° C. for 4 hours. After the reacting mixture was concentrated under reduced pressure, to the resulting residue was added methanol and the resulting precipitate was filtered off. After the filtrate was concentrated under reduced pressure, the resulting residue was purified by silica gel column chromatography eluting chloroform-methanol (20:1) chloroform-methanol-concentrated aqueous ammonia (10:10:1) and further purified by preparative thin layer chromatography eluting chloroform-methanol (20:1)→chloroform methanol-concentrated aqueous ammonia (10:10:1→10:10:3) to give the title compound (46 mg) as redish powder, mp 300° C.

Provenance & Evidence