Nadifloxacin isomer 2

Nadifloxacin isomer 2 is a stereoisomeric fluoroquinolone derivative characterized by a 1-cyclopropyl-6-fluoro-8-methoxy-7-piperazin-1-yl-1,4-dihydro-4-oxoquinoline-3-carboxylic acid scaffold with an inverted configuration at the chiral center adjacent to the piperazine moiety. This structural deviation from the parent drug results in altered conformational flexibility and hydrogen bonding capacity. The compound serves as a critical HPLC reference standard for quantifying enantiomeric impurities in nadifloxacin active pharmaceutical ingredient synthesis.