Phenyldiimide, hemoglobin, and Heinz bodies.

Phenylhydrazine is oxidized stoichiometrically by two equivalents of ferricyanide to produce phenyldiimide and ferrocyanide. This reaction permits accurate determination of the absorption maxima and molar absorption coefficients of phenyldiimide in aqueous solution. These values are identical or extremely similar to those of phenyldiimide produced by decarboxylation of phenylazoformic acid. Knowledge of the stoichiometry of the reaction confirms an earlier suggestion that phenyldiimide is the product of ferricyanide-oxidized phenylhydrazine that reacts with heme proteins. Homologous structures postulated for phenyldiimideferrihemoglobin and nitrosobenzeneferrohemoglobin suggest a common factor in the production of Heinz bodies after exposure of erythrocytes to phenylhydrazine and to arylamines.