title: Distinguishing isobaric phosphated and sulfated carbohydrates by coupling of mass spectrometry with gas phase vibrational spectroscopy.
abstract: An original application of the coupling of mass spectrometry with vibrational spectroscopy, used for the first time to discriminate isobaric bioactive saccharides with sulfate and phosphate functional modifications, is presented. Whereas their nominal masses and fragmentation patterns are undifferentiated by sole mass spectrometry, their distinctive OH stretching modes at 3595 cm(-1) and 3666 cm(-1), respectively, provide a reliable spectroscopic diagnostic for distinguishing their sulfate or phosphate functionalization. A detailed analysis of the 6-sulfated and 6-phosphated d-glucosamine conformations is presented, together with theoretical scaled harmonic spectra and anharmonic spectra (VPT2 and DFT-based molecular dynamics simulations). Strong anharmonic effects are observed in the case of the phosphated species, resulting in a dramatic enhancement of its phosphate diagnostic mode.
authors.affiliation: Université de Lyon, F-69622, Lyon, France.
authors.forename: Baptiste
authors.initials: B
authors.lastname: Schindler
authors.forename: Janhavi
authors.initials: J
authors.lastname: Joshi
authors.forename: Abdul-Rahman
authors.initials: AR
authors.lastname: Allouche
authors.forename: Daniel
authors.initials: D
authors.lastname: Simon
authors.forename: Stéphane
authors.initials: S
authors.lastname: Chambert
authors.forename: Vincent
authors.initials: V
authors.lastname: Brites
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Gaigeot
authors.forename: Isabelle
authors.initials: I
authors.lastname: Compagnon
mesh_terms: D005740:Gases / Q000737:chemistry; D005944:Glucosamine / Q000031:analogs & derivatives* / Q000737:chemistry*; D019298:Glucose-6-Phosphate / Q000031:analogs & derivatives* / Q000737:chemistry; D013058:Mass Spectrometry; D008968:Molecular Conformation; D011789:Quantum Theory; D013055:Spectrophotometry, Infrared
chemical_list: D005740:Gases; C001293:glucosamine 6-phosphate; D019298:Glucose-6-Phosphate; D005944:Glucosamine