| Abstract: | Deuterium labeling and high resolution mass spectroscopy have been used to determine the modes of electron impact fragmentation of 3,3-dimethyl-1-methylthio-2-butanone O-[(methylamino)carbonyl]oxime, thiofanox and its metabolites, the sulfoxide and sulfone. The mass spectra of the corresponding oximes were also examined. The carbamates fragmented chiefly by two competing pathways—the loss of CH3N?C? O or the sulfur-containing moiety. The favored process was dependent on the oxidation state at sulfur. Several unusual rearrangements were noted. |
