CHARACTERIZATION OF STEREOISOMERIC ALPHA-METHYLENE-GAMMA-LACTONE FURANOSIDIC DERIVATIVES BY DIRECT CHEMICAL-IONIZATION MASS-SPECTROMETRY AND LIQUID SECONDARY-ION MASS-SPECTROMETRY WITH TANDEM MASS-SPECTROMETRY

Several furanosidic derivatives have been found to have biological act ivity and have been used both as fungicides and plant growth regulator s. In particular, those carbohydrate derivatives that contain the alph a-methylene-gamma-lactone unit have interesting potential applications , The present study deals with the mass spectrometric characterization of furanosidic compounds having a alpha-methylene-gamma-lactone unit, using different ionization techniques: chemical ionization mass spect rometry and liquid secondary ion mass spectrometry together with metas table ion analysis and high-energy collision-induced dissociation, The objective of this study was to determine the influence on the respect ive fragmentation patterns of structural differences present in the st ereoisomers. Common fragmentation differences relate to the extent of the loss of water which occurs together with the loss of acetone and t o the formation of C7H7+ ions.