In vitro clastogenicity of optical isomers of nadifloxacin.
The potential of optical isomers of the fluoroquinolone antibacterial agent nadifloxacin (NDFX, CAS 124858-35-1) to induce chromosomal aberrations in vitro was investigated in cultured Chinese hamster lung (CHL) cells for 24 h of continuous treatment. S- and R-enantiomers of NDFX showed significant differences in the results of the chromosomal aberration test, but no marked differences in the results of cytotoxicity test, i.e., S-NDFX induced chromosomal aberrations, but R-NDFX did not. These results were equivalent to those obtained with ofloxacin (OFLX, CAS 83380-47-6), which has a chemical structure similar to that of NDFX. Moreover, although neither NDFX nor OFLX induced aberrations, their mixtures, prepared from equal amounts of S- and R-enantiomers, did. This finding suggests that the racemic compound and the mixture of S- and R-enantiomers exist under different conditions within the solution.
Drug Safety Research Center, Otsuka Pharmaceutical Co., Ltd., Tokushima, Japan.
N
N
Takahashi
T
T
Shiragiku
T
T
Itoh
E
E
Kaneko
T
T
Shibahara
T
T
Kanbe
S
S
Yamashita
D000818:Animals; D000890:Anti-Infective Agents / Q000633:toxicity*; D002460:Cell Line; D002869:Chromosome Aberrations / Q000235:genetics; D006224:Cricetinae; D003412:Cricetulus; D024841:Fluoroquinolones; D009152:Mutagenicity Tests; D009153:Mutagens / Q000633:toxicity*; D015242:Ofloxacin / Q000633:toxicity; D011807:Quinolizines / Q000633:toxicity*; D013237:Stereoisomerism
D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D009153:Mutagens; D011807:Quinolizines; C062127:nadifloxacin; D015242:Ofloxacin