N-Hydroxylamine Dapsone

N-Hydroxylamine Dapsone is a structurally related impurity derived from dapsone via hydroxylamine substitution on the aromatic amine moiety. It features a 4-sulfonamidobenzenamine core with an N-hydroxyl group appended to the secondary amine, conferring increased nucleophilicity compared to the parent compound. The molecule exhibits planar aromaticity with electron-withdrawing sulfone and hydroxylamine functionalities that modulate its redox reactivity. This compound arises as a specific oxidation byproduct during dapsone synthesis or storage under acidic conditions. It serves as an HPLC reference standard for quantifying process-related impurities in dapsone formulations.