FAST-ATOM-BOMBARDMENT MASS-SPECTROMETRY FOR THE CHARACTERIZATION OF TAXANES

Fast atom bombardment mass spectrometry (FABMS) of several taxanes and 11(15-->1)abeo-taxanes having a 4(20)-exocyclic methylene group or ox etane ring was studied in detail using collision-induced dissociation (CID) of their [M+Li](+), [M+Na](+) and [M+NH4](+) ions. The results i ndicate that FAB followed by MS/MS is a valuable tool for the identifi cation of functional groups in taxanes and to some extent the type of taxane under investigation. The presence of hydroxy groups in the mole cule is best confirmed by examining the CID of the [M+NH4](+) adduct i ons. The 11(15-->1)abeo-taxanes are characterized by elimination of th e hydroxy-isopropylidene group with an acetoxy or benzoyloxy group. (C ) 1997 by John Wiley & Sons, Ltd.