Glycuronic acids 1- esters

Base-catalyzed esterification of D-glucurono-6,3-lactone proceeds smoothly at room temperature.242 The acetylated glycuronic acids, and the per-O-acetylglycosyluronic halides of their methyl esters, are important precursors for the synthesis of glycosiduronic acids. D-Glucofuranurono-6,3-lactone... 

The literature on /3-D-glucosiduronic acids is particularly voluminous, and the subject has been extensively reviewed from several aspects. Section III, dealing with this class of compounds, is devoted more to a general overview of their preparation, characterization, and reactions than to individual members. On the other hand, the categories of 1-esters of glycuronic acids and of (glycosylamine)uronic acids, which appear not to have been treated previously as separate topics, receive relatively more attention. 

Oxidations involving 2-ketose or glycuronic acid residues also give satisfactory data ° the acids being best examined in the ester form in order to minimize overoxidation. Periodate oxidation is effective as well for structural elucidation of sialic acid-containing oligosaccharides. ... 

In human pregnancy urine, the hormone is chiefly oestrone in urine of the cow or mare, it is chiefly oestriol. Both oestrogens are excreted as inactive esters of glycuronic acid, until the onset of labour, when they appear in the free form (Cohen and Marrian, 1935). 

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