Table 3

Molecular ions observed for gemifloxacin and its metabolites by HPLC-MS and HPLC/MS-MS

Compound3-aRetention TimeM+ H+Daughters (M + H+)
min
Gemifloxacin (SB-265805)24.0390291, 313, 328
E-Isomer of gemifloxacin20.5390291, 313, 328
Gemifloxacin acyl glucuronide9.1566390
N-Acetyl gemifloxacin (SB-414000)38.0432291, 329, 335
Hydroxymethyl gemifloxacin (SB-414007)40.0391291, 311, 330
O-Desmethyl gemifloxacin (SB-414006)16.7376330, 359
Carboxylic acid derivative of gemifloxacin28.2405330, 361
Gemifloxacin glutamate28.4519327, 371, 426, 455, 473, 501
  • 3-a  Reference compound used is indicated in parentheses.