Analysis of impurity in caderofloxacin / 药学学报

ABSTRACT

<p><b>AIM</b>To analyse the main impurity of caderofloxacin.</p><p><b>METHODS</b>The impurity of caderofloxacin was analysed and determinated by RP-HPLC/ESI/MS with a Zorbax SB-C18 (150 mm x 4.6 mm ID, 5 microns) column. The mobile phase was acetonitrile-0.5% acetic acid solution (1783). A compound was synthesized 1-cyclopropyl-8-(difluoromethoxy)-6-fluoro-1, 4-dihydro-7-(1-piperazinyl)-4-oxo-3-quinoline carboxylic acid (DMCA). Its HPLC chromatogram, UV and MS spectrum were compared with those of the impurity in caderofloxacin.</p><p><b>RESULTS</b>The molecular weight of the impurity was 14 less than that of caderofloxacin. It means the impurity was a CH2-group less than caderoflixacin. The tR, UV and MS of DMCA were the same as those of the impurity in caderofloxacin.</p><p><b>CONCLUSION</b>Based on the tR (HPLC), UV and MS, the impurity of caderofloxacin is confirmed as DMCA.</p>