Structure and Interrelation of the Free Radical Species and the Precursor Produced by the Reaction of Dehydro-L-ascorbic Acid and Amino Acid

Abstract

A product which changes readily to a stable blue, free radical species was isolated from the reaction mixture of dehydro-L-ascorbic acid and an amino acid, and was identified as tris-(2-deoxy-2-L-ascorbyl)amine. Chemical studies using acetone derivatives and analogous compounds confirmed its 3-fold symmetrical structure. These studies also confimred that the above compound was oxidized to a stable free radical retaining a symmetrical structure, and was oxidized further to a known red pigment, the oxidized form of bis(2-deoxy-2-L-ascorbyl)amine with the elimination of one molecule of ascorbic acid.