Four positional isomers of sialyloligosaccharides isolated from the urine of a patient with sialidosis.

Four positional isomers of sialyloligosaccharides were isolated from the urine of an adult patient with sialidosis with partial deficiency of beta-galactosidase. From structural studies including compositional sugar analysis, exoglycosidase digestion, chemical ionization mass spectrometry, proton nuclear magnetic resonance spectrometry, and methylation analysis, their structures were deduced to be as follows: 1. AcNeu alpha 2 leads to 3 Gal beta 1 leads to 4GlcNac beta 1 leads to 2Man alpha 1 leads to 3Man beta 1 leads to 4GlcNac 2. AcNeu alpha 2 leads to 3Gal beta 1 leads to 4GlcNac beta 1 leads to 2Man alpha 1 leads to 6Man beta 1 leads to 4GlcNac 3. AcNeu alpha 2 leads to 6Gal beta 1 leads to 4GlcNac beta 1 leads to 2Man alpha 1 leads to 3Man beta 1 leads to 4GlcNac 4. AcNeu alpha 2 leads to 6Gal beta 1 leads to 4GlcNac beta 1 leads to 2Man alpha 1 leads to 6Man beta 1 leads to 4GlcNac Sialyloligosaccharides 1 and 3 have previously been found in the liver and urine of patients with mucolipidosis I, II, and variable forms, but sialyloligosaccharides 2 and 4 have not previously be found in human urine.