Dialuric acid

Alloxan forms an oxime (1007) which is the same compound, violuric acid, as that formed by nitrosation of barbituric acid likewise, a hydrazone and semicarbazone. Reduction of alloxan gives first alloxantin, usually formulated as (1008), and then dialuric acid (1004 R = OH) the steps are reversible on oxidation. Vigorous oxidation with nitric acid and alkaline hydrolysis both give imidazole derivatives (parabanic acid and alloxanic acid, respectively) and thence aliphatic products. Alloxan and o-phenylenediamine give the benzopteridine, alloxazine (1009) (61MI21300). 

Isodialuric acid See Dialuric acid (probably the same)... 

Tanner,from infrared spectral work, tentatively concluded that 4,6- and 4,5-dihydroxy- and 4,5,6-trihydroxy-pyrimidines exist in the monooxo forms 117, 118 (X = H), and 118 (X — OH), respectively these conclusions are supported by ultraviolet spectral data and chemical evidence. " 2,4,5,6-Tetrahydroxypyrimidine has been isolated in two forms—dialuric acid and isodialuric acid, usually formulated as 119 and 120, respectively, on the basis of rather convincing chemical evidence [for a review see reference 109(f) cf. reference 178]. Isodialuric acid is converted into dialuric acid by base as would be expected if structures 119 and 120 are correct. On the basis of its infrared spectrum, dialuric acid has been concluded to exist in the tetrahydroxy form, but the correctness of this conclusion appears very doubtful. 

Alloxantin has been obtained by the oxidation of uric acid with nitric acid, followed by reduction with hydrogen sulfide 2 by oxidation of uric acid with potassium chlorate, followed by reduction with stannous chloride by condensation of alloxan with dialuric acid in aqueous solution and by oxidation of dialuric acid. ... 

Gregory, J. prak. Chem., [1], 32,278 (1844), showed that dialuric acid gave a white precipitate with barium ion, but that it was readily oxidized by air to alloxantine, which gave a purple precipitate. The role of air in the formation of a purple barium salt from dialuric add was also appreciated by Liebig and Wohler, Ann. Chem., 26, 279 (1838). For a modem interpretation of the color of barimn alloxantinate, see Hantzsch, Ber. chem. Ges., 54, 1267 (1921) and Retinger, J. Am. Chem. Soc., 39, 1059 (1917). 

Clay et al. [65] showed clear correlation between the oxidative reactivity of dialuric acid monohydrate and prevailing moisture contents. Below 93% relative humidity the drug was reasonably stable, oxidation occurring over a 2-month period, whereas the same reaction took less than a day at humidities in excess... 

Diaeudesmin 13C NMli, 4, 576 Di-/3-alanyl conformation, 7, 703 Dialuric acid acidic pKa, 3, 60 oxidation, 3, 74 synthesis, 3, 149... 

Cohen G, Heikkila R (1974) The generation of hydrogen peroxide, superoxide radical, and hydroxyl radical by 6-hydroxydopamine, dialuric acid and related cytotoxic agents. J Biol Chem 249 2447-2452... 

Typical decay pathways, with tetroxides as short-lived intermediates (Chapter 8.8), lead to Ug, dialuric acid and O2 [reaction (125)], as well as to two mol dialuric acid and H2O2 [reaction (126)]. 

The dCyd oxidation products 5-hydroxy-dCyd and 5-hydoxy-dUrd have low oxidation potentials (Wagner et al. 2004) and are hence likely to be oxidized further. For this reason the oxidation of 4-hydroxy-dUrd has been studied (Riviere et al. 2004). Using Br2 or Na2IrBr6 but also menadione plus UV as oxidants, the main oxidation products were the isodialuric acid, dialuric acid and hydantoin derivatives. 

Riviere J, Bergeron F, Tremblay S, Gasparutto D, Cadet J, Wagner JR (2004) Oxidation of 5-hydroxy-2 -deoxyuridine into isodialuric acid, dialuric acid and hydantoin products. J Am Chem Soc 126 6548-6549... 

Clay RJ, Knevel AM, Byrn SR. The desolvation and oxidation of crystals of dialuric acid monohydrate. J Pharm Sci 1982 71 1289-1291. 

Alloxan (233)235 gives in acid solution a kinetically controlled polarographic wave the rate-controlling process involved may be the dehydration of the hydrated carbonyl at C-5. The reduction product, dialuric acid (234), can be anodic reoxidized to alloxan or, between pH 4.6 and 6.6, reduced further, probably to barbituric acid (235). 

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