A gas chromatographic-mass spectrometric method for the determination of S-methyl-l- cysteine sulfoxide (1), S-propyl-l-cysteine sulfoxide (2), and S-propenyl-l-cysteine sulfoxide (3), specific marker compounds in the genus Allium, is described. The target amino acids were converted to the tert-butyldimethylsilyl derivatives. The products were silylated on the amino and carboxyl groups and on an additional oxygen atom and were separated on a ...
