Mass spectra of various deuterium-labelled forms of bis-O-trimethylsilyl-N-acetylsphinganine

The mass spectrum of the trimethylsilyl derivative of N-acetylsphinganine (dihydrosphingosine) has been studied in detail. Origins, structures and mechanisms of formation of the principal ions are supported by deuterium labelling and exact masses. The ions formed on electron impact ionization at 70 eV can be divided into two main categories with respect to electron abstraction from one of the oxygen atoms or the nitrogen atom on the long-chain carbon backbone.