More than twenty synthesized S-containing amino acids and peptides with biological interests, have been measured by direct inlet system of the mass spectrometer. Most of these compounds have the large molecular ion abundances and give the reproducible fragmentations. The mass spectral-fragmentation mechanisms of systematically synthesized S-alkyl-l-cysteines, S-alkyl-l-cysteine sulphoxides, S-alkyl-2-methyl-dl-cysteines, glycyl-S- ...
