The Absolute Configuration of (R)-(+)-Nadifloxacin

Abstract

The optically active (+)-enantiomer of 5, 6-difluoro-2-methyl-1, 2, 3, 4-tetrahydroquinoline was obtained as a salt with dibenzoyl-D-tartaric acid by the optical resolution method and was determined to be R-configuration by X-ray analysis. Since (R)-(+)-5, 6-difluoro-2-methyl-1, 2, 3, 4-tetrahydroquinoline is the optically resolved synthetic intermediate of optically active (+)-enantiomer of nadifloxacin[9-fluoro-6, 7-dihydro-8-(4-hydroxy-1-piperidyl)-5-methyl-1-oxo-1H, 5H-benzo[i, j]quinolizine-2-carboxylic acid, OPC-7251, 1], the absolute configuration of (±)-1 was assigned to R.