Electrospray ionization mass spectrum of S-Acyl-2-thioethyl phosphoramidate diester derivatives

The fragmentation pathways of three S-Acyl-2-thioethyl (SATE) phosphoramidate diester derivatives were studied in detail on tandem electrospray ionization mass spectrometry (ESI-MSn) in positive mode. A novel rearrangement of the SATE moiety was observed. The loss of 60 u from the SATE moiety was found in the ESI-MS2.