Figure 5. N^α-acetyl-lys-imine (A) and N^α-acetyl-2-aminoadipic semialdehyde (B) are detected in the reaction of N^α-acetyl-lys with HOCl (1000:1).

Generation of N^α-acetyl-lys-imine and N^α-acetyl-2-aminoadipic semialdehyde intermediates were detected by Triple-TOF high resolution mass spectrometry as described under Materials and Methods. Exact mass of both precursor and product ions of the identified molecules match with those of the calculated masses of the proposed reaction intermediates as shown, respectively.