title: Post-source decay matrix-assisted laser desorption/ionization mass spectrometric study of tetracyclic 2,3-dihydro-1,5-benzothiazepines.
abstract: The fragmentation behavior of six tetracyclic 2,3-dihydro-1,5-benzothiazepine derivatives cationized with protons and silver ions under post-source decay (PSD) matrix-assisted laser desorption/ionization (MALDI) conditions is reported. The protonated adduct ions decompose into several structurally important fragment ions, including substituted cyclopropane and benzohydrothiazole cations. Elimination of Ag and H and/or AgH from the silver-cationized adduct ions of these ([M+Ag](+)) compounds was observed. It was also found that [M+Ag](+) produced silver-depleted fragment ions exclusively. Based on the PSD results a fragmentation pathway is proposed for the [M+H](+) and [M+Ag](+) precursor ions.
authors.affiliation: Department of Applied Chemistry, University of Debrecen, H-4010 Debrecen, Hungary.
authors.forename: Sándor
authors.initials: S
authors.lastname: Kéki
authors.forename: Lajos
authors.initials: L
authors.lastname: Nagy
authors.forename: György
authors.initials: G
authors.lastname: Deák
authors.forename: Albert
authors.initials: A
authors.lastname: Lévai
authors.forename: Miklós
authors.initials: M
authors.lastname: Zsuga
mesh_terms: D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013841:Thiazepines / Q000032:analysis* / Q000737:chemistry
chemical_list: D013841:Thiazepines