Levofloxacin is a broad-spectrum third-generation fluoroquinolone and one of the isomers of ofloxacin, specifically the optical S-(-) isomer. It is a DNA gyrase inhibitor shown to inhibit topoisomerase IV. Levofloxacin was synthesized by scientists at Daiichi Pharmaceutical Co. Ltd (Tokyo, Japan) and is one of the later generation fluoroquinolones referred to as 'respiratory quinolones' to distinguish them from earlier fluoroquinolones which had modest activity towards Streptococcus pneumoniae. It acts as a bactericide. Levofloxacin is called a chiral switch (a chiral compound that has been approved as a racemate but has been re-developed as a single enantiomer. It can be used ot study antibiotic resistance.
Levofloxacin is soluble in glacial acetic acid and chloroform. It is insoluble in water.