Liquid secondary ion mass spectrometry and collision-induced dissociation mass spectrometry of sulfonamide derivatives of meso-tetraphenylporphyrin

Liquid secondary ion mass spectrometry (LSIMS) and collision-induced dissoc iation (CID) were used for the characterization of sulfonamide derivatives of meso-tetraphenylporphyrin (TPP). The spectra obtained using LSIMS show a bundant molecular ions and fragment ions from losses of the sulfonamide moi eties. The main fragmentation observed in the LSI mass spectra and in the C ID spectra of the protonated or cationized molecules involves the loss of o ne sulfonamide group. In addition, in the CID spectra of these compounds th e fragment ions formed by the elimination of two, three and/or four sulfona mide groups are also observed. The CID spectra of the protonated or cationi zed molecules of these derivatives do not display the ions formed by the cl eavage of the S-N bond which have been reported for other sulfonamide compo unds. The LSI mass spectra and CID spectra of sulfonamide derivatives of me so-tetraphenylporphyrin provide an easy and reliable means of identificatio n of the number and nature of sulfonamide groups in the porphyrinic ring. C opyright (C) 1999 John Wiley & Sons, Ltd.