High resolution mass spectrometry in molecular structure studies—VI: The fragmentation of amaryllis alkaloids in the crinine series. Compounds bearing a hydroxyl substituent at C‐11 (and some 11‐oxo derivatives)

Abstract

Abstract High resolution mass spectral fragmentation patterns of Amaryllidaceae alkaloids in the crinine series bearing a substituent at C‐11 have been investigated, as well as certain isotopically labeled derivatives. The substituent at C‐11 governs almost entirely the fragmentation pattern of these bases due to the ability of the hydroxylic hydrogen atom to rearrange. In contrast to the bases lacking this hydrozyl substituent, stereochemistry exerts a profound influence on the fragmentation.