Characterization of a scyllo-inositol-containing sialyloligosaccharide from normal human urine.

Three inositol-containing sialyloligosaccharides were isolated from normal human urine. Structural studies including gas-liquid chromatography of mono- and disaccharide derivatives, methylation analysis, mass spectrometry and glycosidase treatments indicated the structure NeuAc (alpha 2-3)Gal(beta 1-0)scyllo-inositol for one of the oligosaccharides isolated. This provides the first evidence for the natural occurrence of a scyllo-inositol glycoside in biological material. The two other oligosaccharides isolated were identified as two isomers of NeuAc(alpha 2-3)Gal(beta 1-0)myo-inositol, which have not been identified in normal urine before.