title: Chromatography and high-resolution mass spectrometry for the characterization of the degradation products of the photodegradation of amidosulfuron: an analytical approach.
abstract: Simulated sunlight irradiation causing degradation of amidosulfuron, a pyrimidinylsulfonylurea herbicide, has been investigated in aqueous solution. The main degradation products were followed up by ultrahigh-pressure liquid chromatography with a UV detector (UHPLC-UV) and identified by combining ultrahigh-pressure liquid chromatography-mass spectrometry (UHPLC-MS) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). On the basis of the retrosynthetic analysis, the most identified degradation products were mainly due to the losses of methylsulfamic acid (CH₅NO₃S), sulfocarbamic acid (CH₃NO₅S), carbamic acid (CH₃NO₂), methyl(methylsulfonyl)sulfamic acid (C₂H₇NO₅S₂), N-methylmethanesulfonamide (C₂H₇NO₂S), and sulfonic acid (H₂SO₄) molecules. Accordingly, O and S-demethylation as well as hydroxylation processes were also observed. Sum formulas of the main degradation products were assigned, and a mechanical pathway is proposed.
authors.affiliation: Research Unit Analytical BioGeoChemistry, German Research Center for Environmental Health, Helmholtz-Zentrum Muenchen , Ingolstaedter Landstrasse 1, D-85764 Neuherberg, Germany.
authors.forename: Mourad
authors.initials: M
authors.lastname: Harir
authors.forename: Amina
authors.initials: A
authors.lastname: Chnirheb
authors.forename: Basem
authors.initials: B
authors.lastname: Kanawati
authors.forename: Mohammed
authors.initials: M
authors.lastname: El Azzouzi
authors.forename: Philippe
authors.initials: P
authors.lastname: Schmitt-Kopplin
mesh_terms: D002851:Chromatography, High Pressure Liquid; D017357:Cyclotrons; D004350:Drug Residues / Q000032:analysis / Q000737:chemistry / Q000528:radiation effects; D004355:Drug Stability; D005583:Fourier Analysis; D006540:Herbicides / Q000032:analysis / Q000737:chemistry* / Q000528:radiation effects; D006900:Hydroxylation / Q000528:radiation effects; D008745:Methylation / Q000528:radiation effects; D015394:Molecular Structure; D010782:Photolysis; D011743:Pyrimidines / Q000032:analysis / Q000737:chemistry* / Q000528:radiation effects; D021241:Spectrometry, Mass, Electrospray Ionization; D013056:Spectrophotometry, Ultraviolet; D013453:Sulfonylurea Compounds / Q000032:analysis / Q000737:chemistry* / Q000528:radiation effects; D013472:Sunlight / Q000009:adverse effects
chemical_list: D006540:Herbicides; D011743:Pyrimidines; D013453:Sulfonylurea Compounds; C508353:amidosulfuron