Dialuric acid

Structural formula
General
Surname	Dialuric acid
other names	5-hydroxy-2,4,6 (1 H , 3 H , 5 H ) -pyrimidinetrione ( IUPAC ) 5-hydroxybarbituric acid
Molecular formula	C 4 H 4 N 2 O 4
Brief description	colorless, crystallizing with 1 mol of water
External identifiers / databases
CAS number 444-15-5 42608-53-7 (mono hydrate ) EC number 207-145-0 ECHA InfoCard 100.006.497 PubChem 179547 ChemSpider 156284 Wikidata Q27145999
properties
Molar mass	144.09 g mol −1
Physical state	firmly
Melting point	224 ° C
solubility	soluble in hot water, alcohol, acetone
safety instructions
GHS hazard labeling no classification available
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Dialuric acid is an organic acid , which by the action of hydrogen sulfide and other reducing agents on alloxan forms.

properties

There are 3 other tautomeric forms of dialuric acid . In addition to the 5-hydroxy-2,4,6-pyrimidinetrione structure, these are 5,6-dihydroxy-2,4-pyrimidinedione (isodialuric acid), 4,5,6-trihydroxy-2-pyrimidone and pyrimidine-2,4, 5,6-tetraol.

Tautomerism in dialuric acid

Dialuric acid crystallizes in long needles with a sour taste, which dissolve easily in water, turn red in the air and gradually turn into alloxan. The ammonia salt is prepared by passing hydrogen sulfide gas through a boiling solution of alloxanthine and the like. the liquid then saturates with carbonate of ammonia . It crystallizes in needles that turn rose-red at ordinary temperature and blood-red when dried out. It is easily soluble in boiling water, barite salts fall white, lead salts yellow, silver salts are reduced by these salts. The potash salt is characterized by its low solubility in water, even in boiling water. It is obtained as a yellow crystalline precipitate when one adds cyanide to a solution of alloxane. It is obtained colorless by dissolving the yellow precipitate in potash and saturating it with acetic acid . It then forms a white cheesy precipitate. It can also be represented by dissolving dialuric acid in hydrochloric acid and saturating it with carbonate of potash. The barite salt is a white precipitate. The lead salt is a yellow, flaky precipitate that quickly decreases in volume in the air and turns purple.

Dialuric acid forms with alloxan (a strong oxidant ), a hemiacetal , which alloxantin is called.

Alloxan reacts with dialuric acid to form alloxantin

literature

• GM Richardson: The autoxidation of dialuric acid. In: The Biochemical journal. Volume 26, Number 6, 1932, pp. 1959-1977, PMID 16745025 , PMC 1261125 (free full text).

Individual evidence

1. ↑ ^{a b c} Entry on dialuric acid. In: Römpp Online . Georg Thieme Verlag, accessed on March 24, 2020.
2. ↑ This substance has either not yet been classified with regard to its hazardousness or a reliable and citable source has not yet been found.
3. ↑ External identifiers or database links for isodialuric acid : CAS number: 102636-37-3, PubChem : 67956 , ChemSpider : 61271 , Wikidata : Q1208512 .
4. ↑ Dialuric acid . In: Heinrich August Pierer : Pierers Universal-Lexikon , Vol. 5 . Altenburg 1858, pp. 104-105.