Abstract
Prostaglandins (PGs) are biologically active metabolites of arachidonic acid containing 20 carbon atoms, a cyclic moiety, and two side chains (A and B) in common. The bioassay of PGs requires high sensitivity because of their low concentration in tissues and blood and has usually been carried out by electrospray ionization tandem mass spectrometry (ESI-MS/MS) in the negative ion mode. Chemical derivatization of PG carboxylic acid groups to introduce positive charge-carrying groups is an established strategy to improve the sensitivity and selectivity of such assays. In this study, we exploited this approach for structural identification of a series of PGs using cholamine derivatization through an amidation reaction. However, we observed that collision-induced dissociation of these derivatives gave rise to unexpected product ions that we postulated were formed by unique long-range intramolecular reactions resulting in dehydration of the B chain accompanied by fragmentation of the A chain through an unusual Hofmann rearrangement. Evidence for the proposed mechanism is presented based on ESI-MS/MS and high resolution mass spectrometry studies of cholamine derivatives of PGE1, PGE2, PGD2, PGI2, and C-17 methyl deuterium-labeled limaprost. Graphical Abstract.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of the American Society for Mass Spectrometry
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
