Sialic acids. XII. On the nature of the acylneuraminic acids from human normal urine

Abstract

After a survey of the bibliography on the nature of the acylneuraminic (or sialic) acids from several human products, it may be deduced that N-acetylneuraminic ac’d is the main sialic acid; but the possibility of the existence in the human specie of other acids as N-glycolylneuraminic acid and pluriacetylneuraminic acids, even at little amounts, may not be excluded.
Using mild methods for fractionation of the adialyzate of human urine with Sepha­dex, BioGel, etc., and paper chromatography for analysis, it seems that a N,O,diacetyl- neuraminic acid (probably the N-acetyl-4-O-acetylneuraminic acid) is present, bound and free, in some fractions of the material; yet, further work is required to confirm this result.