Aldobionic acid

A series of derivatives analogous to those from o-glucuronic acid has been made by Morell and Link. An important compound is the crystalline methyl ester of methyl a-n-galaoturonoside (XXXII) which on alkaline hydrolysis yields methyl a-D-galacturonoside (XXXIII). Since 

The pyranose structure of D-galaoturonic acid, which lactonizes with great difficulty, has been confirmed by Levene and Kreider from a study of the methylated ester of the uronoside. Methyl a-o-galactu-ronoside (XXXIII) was methylated with silver oxide and methyl iodide and there was obtained methyl 2,3,4-trimethyl-a-n-galacturonoside methyl ester (XXXVI) which on oxidation was converted to n,l(2,3,4-trimethylmucic) acid (XXXVII) and L-oraho-trimethoxyglutaric acid (XXXVIII). 

A series of crystalline salts of n-galacturonic acid has recently been prepared by Isbell and Frush. Some of these, e. g., calcium sodium D-galacturonate, are suitable for the separation of n-galacturonic acid from plant materials. 

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A number of derivatives of D-glucuronic acid have been made by Goebel and Babers37 with a view to their use in the synthesis of aldobionic acids. With the same object Owen, Peat and Jones38 prepared both pyranose and furanose derivatives of D-glucurone. 

Species III-V in Scheme 6 are also formed when Cr(V) is generated by reaction of Cr(VI) with GSH (1 1 ratio) at pH 5.0 and stabilized by the presence of a 10-fold excess of the disaccharide over Cr(VI).70 This result provides evidence that the Cr(V) species observed at this pH correspond effectively to Cr(V) chelates formed with the disaccharide and not with the oxidized product (the aldobionic acid). 

Preliminary investigations into the constitution of plant gums have been directed to the isolation of disaccharides or aldobionic acids which are relatively easy to identify. Thus the structures of the aldobionic... 

The same procedure has revealed that the aldobionic acid obtained from damson gum and cherry gum by acid hydrolysis has the structure V. Methylation gives the methyl ether VI and when this is subjected to hydrolysis with dilute mineral acid there results 3,4,6-trimethyl-D-mannose (VII) and 2,3,4-trimethyl-D-glucuronic acid (VIII). 

Further study of the gum of the English cherry tree has shown that it bears many resemblances to damson gum. Both gums for instance upon prolonged hydrolysis give an aldobionic acid which has been proved... 

L-arabinose (an aldobionic acid consisting of D-gaJacturonic acid and D-xylose) 7... 

Simultaneously with the studies just described, acylated nitriles of aldobionic acids were also investigated, and several hexosyl-pentose amides were isolated. Ammonolysis of octa-O-acetylcellobiononitrile (59) afforded55 l,l-bis(acetamido)-l-deoxy-3-0-/3-D-glucopyranosyl-D-arabinitol (60), N-acetyl-3-0-/3-D-glucopyranosyl-D-arabinofuranos-ylamine (61), and a 3-0-/3-D-glucopyranosyl-D-arabinose not previously described in the literature. 

Some microorganisms effect the oxidation of oligosaccharides to glycosid-3-uloses this conversion has been reported for maltose, lactose, and their respective aldobionic acids. Conditions for the oxidation of sucrose by the action of Agrobacterium tumefaciens have been improved and optimized on a molar scale, so that 3-ketosucrose can be produced in 40% yield 449... 

M. Heidelberger and W. F. Goebel, The soluble specific substance of Pneumococcus. V. On the chemical nature of the aldobionic acid from the specific polysaccharide of type III Pneumococcus, J. Biol. Chem., 74 (1927) 613-618. 

The Constitution of Damson Gum. Part I. Composition of Damson Gum and Structure of an Aldobionic Acid (Glycuronosido-2-mannose) Derived from It, E. L. Hirst and J. K. N. Jones,/. Chem. Soc., (1938) 1174-1180. 

The Structure of Almond-tree Gum. Part I. The Constitution of the Aldobionic Acid... 

The Compound Uronic Acids. Structure of the Aldobionic Acid from Gum Arabic, S. W. Challinor, W. N. Haworth, and E. L. Hirst, . Chem Soc., 258 (1931). 

The oxidation of reducing disaccharides (V) leads to the formation of aldobionic acids in a manner similar to the oxidation of aldoses to aldonic acids conditions must be such that the glycosidic linkage is not hydrolyzed. 

Glattfeld and Hanke applied this procedure to the oxidation of maltose hydrate. An aqueous solution of the sugar was shaken with lead carbonate and bromine since lead bromide separated from the reaction mixture, only aeration was necessary to remove the excess bromine, and treatment with silver oxide and hydrogen sulfide removed the last bromide, silver and lead ions. The maltobionic acid was isolated as the calcium salt. Here the neutralization of the hydrobromic acid was beneficial in preventing any hydrolysis of the aldobionic acid. 

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