Mometasone furoate impurity DI

Mometasone furoate impurity DI arises from hydrolytic cleavage of the furoate ester moiety, exposing a free hydroxyl group at the 17β-position of the corticosteroid backbone. This impurity retains the 11β,17α-dimethyl-17-propynyl substituents and the 9α-fluoro-16α-methyl-pregna-1,4-diene core of mometasone, but lacks the furan-2-ylcarbonyl ester linkage. Its polar hydroxyl functionality enhances aqueous solubility compared to the parent drug. This compound serves as a critical HPLC reference standard for quantifying degradation pathways in mometasone furoate formulations.