[Impurity analysis and their structure determination of gatifloxacin].
OBJECTIVE
To analyse the impurities of gatifloxacin.


METHODS
The impurity of gatifloxacin were analysized and determinated by RP-HPLC/electrospray ionization mass spectrometry with a Zorbax SB-C18(4.6 mm x 150 mm ID, 5 microns). The mobile phase was 3% acetic acid/acetonitrile-3% acetic acid/water (15:85). The two compounds were synthesized: 1-cyclopropyl-6-fluoro-1, 4-dihydro-8-methoxy-7-(1-piperazinyl)-4-oxo-3-quinolinecarboxylic acid (DMP) and 1-cyclopropyl-6-fluoro-1, 4-dihydro-8-hydro-7-(3-methy-1-piperazinyl)-4-oxo-3-quinolinecarboxylic acid (DMO). Their liquid chromatogram, UV, MS were compared with those of the impurity of gatifloxacin.


RESULTS
The mass of the impurity was 14 less than that of gatifloxacin. It means the impurity was CH2 less than gatifloxacin. The tR (HPLC), UV and MS of DMP were the same as those of the impurity of gatifloxacin.


CONCLUSIONS
Based on the tR (HPLC), UV and MS, the impurity of gatifloxacin is confirmed as DMP.
Zhou
Hong-hua
HH
Center for Instrumental Analysis, China Pharmaceutical University, Nanjing 210009, China. Honghua.zhou@sohu.com
Gao
Song-mei
SM
Wang
Er-hua
EH
Shen
Wen-bin
WB
Sheng
Long-sheng
LS
D000890:Anti-Infective Agents / Q000032:analysis / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D024841:Fluoroquinolones / Q000032:analysis / Q000737:chemistry* / Q000302:isolation & purification*; D000077734:Gatifloxacin; D015394:Molecular Structure; D021241:Spectrometry, Mass, Electrospray Ionization
C479311:1-cyclopropyl-6-fluoro-1,4-dihydro-8-methoxy-7-(1-piperazinyl)-4-oxo-3-quinolinecarboxylic acid; D000890:Anti-Infective Agents; D024841:Fluoroquinolones; D000077734:Gatifloxacin