AM^. Chem. 1994,66, 2330-2335
Class-Selective Collisionally Activated CMseoiertion/ Ion-Molecule Reactions of 4-Qukra)one AntlbloUes Armando Colorado and Jenntfer Brodbelt' Department of Chemistry and Biochemistry, University of Texas, Austin, Texas 78712 A new combinntion of collisionally activated dissociation and ion-molecule reactions in a quadrupole ion trap mass spectrometer is developed for the class-selective determination of 4quindones,anbportmtgroupofantibiotics. Inthismetbod, c d l t p i d y activated dissociPtioa is used to promote dehydration of each protonatedquiaolow, and the resulting dehydrated fragment ion undergoesan addition reaction with an auxiliary reagent. "be auxiliary reagents, including acetone, acetic anhydride, and qropylimiae,bare structuresthat specifically allow formation of a cyclic adduct with the analyte ion. This sequential process is characteristic of a clnss of analyte molecules that have rdjacent carboxylic acid and ketone functional groups anchored on a rigid ring and undergo facile, efficient dehydration.
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