Mass spectrometry of some pyrrolizidine alkaloids

Abstract

The mass spectra of nine pyrrolizidine alkaloids retronecine, heliotridine, 7-angeloylretronecine, 7-angeloylheliotridine, echimidine, heliosupine, lasiocarpine, heliotrine and echinatine— were studied. Particularly the structures of the ions m/e 214, 197 and 156 in the spectrum of heliotrine are discussed. The ionization and appearance potentials for selected ions were measured for the first six alkaloids, which are pairs of epimers.