Glucuronic acid derivatives

A. F. Bochkov and Ya. V. Voznyi, Sugar ortho esters. Part 8. Synthesis of 4-O-methyl-D-glucuronic acid derivatives, Carbohydr. Res., 32 (1974) 1-8. 

Potential, chemotherapeutic activity of this class of compounds stimulated the synthesis313,337,352 of a series of benzimidazole-, pyrimidine-, and purine-substituted nucleosides of D-glucuronic acid derivatives, using, as the starting sugar-component, bromide 1 and methyl (2,3,4-tri-0-acetyl-D-glucopyranosylamine)uronate, respectively. 

Benzyl-protected glucuronic acid derivatives, starting from the methyl gluco-side, have been made earlier by Keglevic et al. [74]. After oxidation and hydrolysis, the compound was transformed into the bromide, which also gave low stereoselectivity in couplings. The corresponding a-linked trichloroacetimidate... 

The brominated sugars are usually quite stable and can be useful for a variety of purposes [151]. Substitution of bromine with deuterium can be used for preparation of labeled carbohydrates, while substitution with hydrogen sometimes can be used for inverting the stereochemistry. Noteworthy is the conversion of D-glucuronic acid derivative 61 into the corre-... 

TSP spectra have much in common with the DLI spectra. Again the protonated or deprotonated aglycon is the major peak in the mass spectrum and thus fits the general characteristic of glucuronic acid conjugates (lfi). Also present were adduct ions, this time with NH4 + or acetate Ac from the 0.1M aqueous ammonium acetate in the mobile phase, which also contained 20% acetonitrile. These adducts were formed from the molecular ion, thermally derived BaPOH and a glucuronic acid derivative. The adduct ions have much in common with chemical ionization spectra (,17.18 ). This may be expected from the dissociation of ammonium acetate and extraction of the ions from the liquid. 

Scheme 6 The use of a glucuronic acid derivative to synthesize hyalobiuronic acid.

The mechanisms for these effects of water are complicated and are determined by the physical state of water molecules. For example, for drugs that form hydrates, water of crystallization is trapped in the crystals and, generally, cannot participate in chemical reactions. This is exemplified by the discoloration of glucuronic acid derivatives.423 As shown in Fig. 95, addition of water in amounts that form water of crystallization does not cause discoloration however, addition of excess water does accelerate the discoloration at a rate proportional to the amount of water not involved in hydrate formation. 

Anthracyclines glycosylated at the 4-position are very rarely mentioned in the literature, and 4-0-(/l-D-glucopyranosyl)-fi-rhodomycinone (39a) isolated from a mutant of Actinomadura roseoviolacea was the first one of this series. It exhibited no antibacterial or cytotoxic activity [66]. However, its glucuronic acid derivative histomodulin (39b), isolated from Streptomyces ruber JCM3131, was reported as an up-regulator of MHC class-I molecules in B16/BL6 cells [67]. 

An ingenious method of preparing methyl a- and 3-L-gulofuranosidurono-6,3-lactone involves reversing the oxidation states of the terminal carbon atoms of a D-glucuronic acid derivative (Scheme The uronoside (23) and the 4,5-unsaturated analogue have been obtained from the bromide (24) by standard methods, the oxidation being achieved by photolysis of the 6-azido compound. 

The synthesis of 1-0-acyl-D-glucuronic acid derivatives has been achieved from the benzyl j3-pyranoside via its 2,3,4,6-tetra-0-(o -ethoxyethyl)derivative. The 1-0-methanesulphonyl ester of D-glucuronic acid was used to prepare acyl derivatives involving the attachment of biliverdin and bilirubin. In model experiments the sulphonate also afforded glucuronosides. D-Glucuronosides have also been prepared by standard Koenigs-Knorr glycosylation from various bile acids and A -tetrahydrocannabinol. ... 

D-glucuronic acid derivatives have also been reported as have... 

The glucuronic acid derivative (40) was prepared by treating the 6,3-lactone with BaO, Ba(OH)2 and benzyl bromide in DMF, whereby both lactone opening and ether formation occurred in situ.59... 

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