title: Structural characterization of case-associated contaminants peak C and FF in L-tryptophan implicated in eosinophilia-myalgia syndrome.
abstract: We have characterized the structures of two case-associated contaminants of the Showa Denko L-tryptophan known to cause eosinophilia-myalgia syndrome (EMS). A combination of on-line accurate mass HPLC-electrospray ionization-mass spectrometry (LC-MS), HPLC-tandem mass spectrometry (LC-MS-MS) and HPLC-in source collision induced dissociation-MS-MS (LC-sCID-MS-MS) allowed the structure determination of both Peak C and FF. Peak C is identified as 3a-hydroxy-1,2,3,3a,8,8a-hexahydropyrrolo-[2-3b]-indole-2-carboxyl ic acid, whereas Peak FF is characterized as 2-(2-hydroxy-indoline)-tryptophan. Both contaminants contain indoline rings, and the significance of this finding is discussed.
authors.affiliation: Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, MN 55905, USA. naylor.stephen@mayo.edu
authors.forename: S
authors.initials: S
authors.lastname: Naylor
authors.forename: B L
authors.initials: BL
authors.lastname: Williamson
authors.forename: K L
authors.initials: KL
authors.lastname: Johnson
authors.forename: G J
authors.initials: GJ
authors.lastname: Gleich
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004340:Drug Contamination; D016603:Eosinophilia-Myalgia Syndrome / Q000139:chemically induced*; D006801:Humans; D007211:Indoles / Q000032:analysis; D013058:Mass Spectrometry; D014364:Tryptophan / Q000009:adverse effects* / Q000031:analogs & derivatives / Q000032:analysis / Q000737:chemistry* / Q000592:standards
chemical_list: C407305:2-(2-hydroxyindoline)tryptophan; C407304:3a-hydroxy-1,2,3,3a,8,8a-hexahydropyrrolo-(2-3b)-indole-2-carboxylic acid; D007211:Indoles; D014364:Tryptophan