A comparison of electron ionization and electrospray behaviours of some N,N´-disubstituted hexahydropyrimidines

LILIANA R. ORELLI; MA. BEATRIZ GARCÍA; ISABEL A. PERILLO; LORIS TONIDANDEL; PIETRO TRALDI

RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM.

John Wiley Sons

Año: 2006 vol. 20 p. 823 - 828

0951-4198

The behaviours of some N, N´-disubstituted hexahydropyrimidines, a class of naturally occurring compounds of biological and biomedical interest, have been studied in both electron ionization (EI) and electrospray ionization (ESI) coupled with collisional experiments (ESI/MSn) conditions. The data so obtained put in evidence that in both conditions the [M-H]+ ions are highly abundant, even if their formation must be justified by two different mechanism, i.e. H loss from M+. species in the case of EI and hydride (H-) abstraction from neutral molecules in the case of ESI. Furthermore, due to the low, step-by-step internal energy deposition typical of collisional experiments performed by ion trap, different fragments have been observed in EI and ESI/MSn collisions. In both cases the fragments are well related to the original structure and allow to identify the positions in which the different substituents are present.