Chemical ionization mass spectra of phenothiazine derivatives and their oxygenated analogs

Twenty-nine derivatives of phenothiazine formed relatively stable ions by proton capture under conditions of chemical ionization, using methane or isobutane as reagent gas. Fragments of generally low abundance formed by simple bond cleavage in the trimethylene portion of the side chain and by loss of water or hydrogen halide. Mass spectra obtained from pyrolyzates of amine salts and from the corresponding free bases were essentially identical.