macitenan hydroxy sulfamide

Macitenan hydroxy sulfamide is a structurally related impurity derived from the parent compound macitenan, featuring a hydroxyl-substituted sulfamide moiety adjacent to the core aromatic scaffold. The hydroxyl group introduces steric and electronic perturbations, altering hydrogen bonding capacity and metabolic stability compared to the parent drug. This impurity arises via nucleophilic substitution at the sulfonamide nitrogen, followed by hydrolytic cleavage. It serves as a critical HPLC reference standard for quantifying process-related impurities in macitenan formulations.