Characteristic features of mass-spectra of some nitroxide radicals

Some compounds containing mono- and polynitroxide radicals have been investigated and characterized by electron ionization (EI), chemical ionization (CI), and matrix-assisted laser desorption-ionization (MALDI) mass spectrometry. Some characteristics of the mass spectra of these radicals are demonstrated. It was found that, under CI and MALDI conditions, ions [M+nH]+ are formed along with monoprotonated molecules [M+H]+, depending on the type of the radical n = 2–5.