UVPD Spectroscopy of Differential Mobility-Selected Prototropic Isomers of Rivaroxaban

Abstract

Two ion populations of protonated Rivaroxaban, [C 19 H 18 ClN 3 O 5 S + H] + , are separated under pure N 2 conditions using differential mobility spectrometry prior to characterization in a hybrid triple quadrupole linear ion trap mass spectrometer. These populations are attributed to bare protonated Rivaroxaban and to a proton-bound Rivaroxaban−ammonia complex, which dissociates prior to mass-selecting the parent ion. Ultraviolet photodissociation (UVPD) and collision-induced dissociation (CID) studies indicate that both protonated Rivaroxaban ion populations are comprised of the computed global minimum prototropic isomer. Two ion populations are also observed when the collision environment is modified with 1.5% (v/v) acetonitrile. In this case, the protonated Rivaroxaban ion populations are produced by the dissociation of the ammonium complex and by the dissociation of a proton-bound Rivaroxaban−acetonitrile complex prior to mass selection. Again, both populations exhibit a similar CID behavior; however, UVPD spectra indicate that the two ion populations are associated with different prototropic isomers. The experimentally acquired spectra are compared with computed spectra and are assigned to two prototropic isomers that exhibit proton sharing between distal oxygen centers.

Vibrational and electronic spectra of protonated vanillin: exploring protonation sites and isomerisation

“…The present research reveals a situation where the analysis of experimental data may not exclusively rely on the lowest calculated energy isomer, especially for low energetic differences. Similar conclusions have been previously obtained by other research groups on different systems, 6,9,66 although, to our knowledge, this is the first work focused on aromatic aldehydes. In addition, this work adds to the growing list of examples showing the power of combining IRMPD and UVPD spectroscopies to determine the molecular structure and/or isomerism (e.g.…”

The hitchhiker's guide to dynamic ion–solvent clustering: applications in differential ion mobility spectrometry

“…These sub-populations can be associated with different conformers or tautomers, 45,48,50,[158][159][160] diastereomers, 44,46,47,139 or with post-DMS fragmentation of an aggregate species (e.g., solvent clusters, proton-bound analyte dimers). 49,161 Although the identity of each feature can be determined by, for example, collision-induced dissociation, 48 hydrogen-deuterium exchange, 162,163 and/or trapped ion spectroscopy, 18,[164][165][166][167][168][169] there is no simple a priori method to determine whether a particular analyte will exhibit multiple features in a DMS ionogram. This complicates the use of DMS in an analytical setting -if an analyte exhibits multiple populations that vary with DMS conditions, but the device is set to select only one sub-population, one runs the risk of underestimating analyte concentration in quantification experiments.…”

Improved First-Principles Model of Differential Mobility Using Higher Order Two-Temperature Theory

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