Fast atom bombardment/collisional activation mass spectrometry of beta-D-mannosyl-(1----4)-beta-D-N-acetylglucosaminyl (1----N) urea and related compounds.

A new compound, obtained during the isolation of oligosaccharides from the urine of two brothers affected with inherited beta-mannosidase deficiency, has been investigated using fast atom bombardment ionization and MS/MS techniques. The compound could be characterized as an N-acetylglucosamine molecule linked to a hexose and a urea molecule.