title: Mass spectrometry as an aid to the identification of ergots and dihydroergots: comparison of hard and soft ionization techniques.
abstract: An analysis of the 70 eV electron impact (EI) and fast atom bombardment (FAB) mass spectral features of a variety of ergoline and dihydroergoline derivatives of therapeutic importance is presented with emphasis upon analytical utility. Derivatives which carry non-peptide based C-8 substituents are fully characterized by EI-MS through provision of molecular wieght evidence and fragment ions diagnostic of both the ergoline skeleton and the C-8 substituent. Peptidic ergolines and dihydroergolines are poorly characterized by EI-MS, but their FAB-MS clearly reveal [M + 1]+ (high intensity) and [M - 1]- (high to low intensity) ions in positive and negative ion spectra, respectively. Negative FAB spectra of salts also display diagnostic anion-base conjugate ions.
authors.affiliation: School of Pharmacy and Pharmacology, University of Bath, Claverton Down, UK.
authors.forename: A F
authors.initials: AF
authors.lastname: Casy
mesh_terms: D001971:Bromocriptine / Q000032:analysis / Q000737:chemistry; D004873:Ergolines / Q000032:analysis* / Q000737:chemistry; D004878:Ergotamine / Q000032:analysis / Q000737:chemistry; D004879:Ergotamines / Q000032:analysis / Q000737:chemistry; D008970:Molecular Weight; D016339:Spectrometry, Mass, Fast Atom Bombardment
chemical_list: D004873:Ergolines; D004879:Ergotamines; D001971:Bromocriptine; C100270:ergocristine; C100269:ergocryptine; C030041:ergosine; C100271:ergocornine; D004878:Ergotamine