We report a collision‐induced dissociation (CID) based gas phase rearrangement study using quadrupole time‐of‐flight mass spectrometry coupled with liquid chromatography on a novel endothelin and angiotensin II receptor antagonist, sparsentan. We performed tandem mass spectrometry to identify precursor and fragment ion relationships and assigned structures for major fragment ions. We propose a benzyl migration mechanism based on bond length measurements in density functional theory (B3LYP/6‐31+G*) optimized geometries of protonated sparsentan and its
Fucose is a signaling carbohydrate that is attached at the end of glycan processing. It is involved in a range of processes, such as the selectin‐dependent leukocyte adhesion or pathogen‐receptor interactions. Mass‐spectrometric techniques, which are commonly used to determine the structure of glycans, frequently show fucose‐containing chimeric fragments that obfuscate the analysis. The rearrangement leading to these fragments—often referred to as fucose migration—has been known for more than 25 years, but the chemical identity of the rearrangement product remains unclear. In this work, we combine ion‐mobility spectrometry, radical‐directed dissociation mass spectrometry, cryogenic IR spectroscopy of ions, and density‐functional theory calculations to deduce the product of the rearrangement in the model trisaccharides Lewis x and blood group H2. The structural search yields the fucose moiety attached to the galactose with an
- Award ID(s):
- 1904577
- NSF-PAR ID:
- 10418509
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 62
- Issue:
- 24
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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