2866. Dehydroascorbic Acid

Nomenclature

CAS number: 490-83-5
l-threo-2,3-Hexodiulosonic acid γ-lactone.
C6H6O6; mol wt 174.11.
C 41.39%, H 3.47%, O 55.14%.

Description and references

The reversibly oxidized form of ascorbic acid. Prepd by the action of benzoquinone on ascorbic acid: Ohle, Erlbach, Ber. 67, 555 (1934); Moll, Wieters, E. Merck's Jahresber. 50, 65 (1936); by the action of iodine: Herbert et al., J. Chem. Soc. 1933, 1270; Kenyon, Munro, ibid. 1948, 158; by oxidn with peri-naphthindan-2,3,4-trione hydrate: Moubasher, J. Biol. Chem. 176, 533 (1948); see also Müller-Mulot, Z. Physiol. Chem. 351, 52 (1970). Isomerization and formn of derivs: Egge, Tetrahedron Lett. 1969, 801. Structure studies: Teichmann, Ziebarth, Z. Prakt. Chem. 33, 124 (1966). Toxicity studies: Gaudiano et al., Boll. Soc. Ital. Biol. Sper. 43, 674 (1967).

Chemical structure

Properties

Fine needles, dec 225°. Sol in water at 60°. In soln the two carbonyl groups (in position 2 and 3) assume the hydrated form ‐C(OH)2‐C(OH)2‐. Practically neutral reaction. pKa: 3.90. [α]D20 +56°. Aq solns are much less stable than those of ascorbic acid. Detailed stability data: Bogdanski, Bogdanska, Bull. Acad. Pol. Sci. Cl. 2 3, 41 (1955). See also Velisek et al., Collect. Czech. Chem. Commun. 37, 1465 (1972). Undecomposed dehydroascorbic acid in soln is easily converted to ascorbic acid by reduction with sulfurous acid. Has same antiscorbutic activity in humans as ascorbic acid (upon oral ingestion).