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The Impact of Leaving Group Anomericity on the Structure of Glycosyl Cations of Protected Galactosides.

ABSTRACT: It has been reported that fragments produced by glycosidic bond breakage in mass spectrometry-based experiments can retain a memory of their anomeric configuration, which has major implications for glycan sequencing. Herein, we use cryogenic vibrational spectroscopy and ion mobility-mass spectrometry to study the structure of B-type fragments of protected galactosides. Cationic fragments were generated from glycosyl donors carrying trichloroacetimidate or thioethyl leaving groups of different anomeric configuration. The obtained infrared signatures indicate that the investigated fragments exhibit an identical structure, which suggests that there is no anomeric memory in B-type ions of fully protected monosaccharides.

SUBMITTER: Greis K

PROVIDER: S-EPMC7540451 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

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The Impact of Leaving Group Anomericity on the Structure of Glycosyl Cations of Protected Galactosides.

Greis Kim K Mucha Eike E Lettow Maike M Thomas Daniel A DA Kirschbaum Carla C Moon Sooyeon S Pardo-Vargas Alonso A von Helden Gert G Meijer Gerard G Gilmore Kerry K Seeberger Peter H PH Pagel Kevin K

Chemphyschem : a European journal of chemical physics and physical chemistry 20200730 17

It has been reported that fragments produced by glycosidic bond breakage in mass spectrometry-based experiments can retain a memory of their anomeric configuration, which has major implications for glycan sequencing. Herein, we use cryogenic vibrational spectroscopy and ion mobility-mass spectrometry to study the structure of B-type fragments of protected galactosides. Cationic fragments were generated from glycosyl donors carrying trichloroacetimidate or thioethyl leaving groups of different an ...[more]

PMID: 32652759

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