Introduction of the α-ketoamide structure: en route to develop hydrogen peroxide responsive prodrugs

Abstract

Leveraging the elevated levels of hydrogen peroxide (H₂O₂) in cancer, inflammatory diseases and cardiovascular disorders, H₂O₂-activated promoieties have been widely used in drugs and biomaterials design. However, the overwhelming majority of the promoieties only share the common structure of a H₂O₂-responsive arylboronic acid/ester moiety with low diversity. We report here an unprecedented strategy to construct novel H₂O₂-responsive prodrugs based on an α-ketoamide structure. As a proof of concept, we designed and synthesized a panel of α-ketoamide based nitrogen mustard prodrugs, among which KAM-2 showed potent growth inhibitory activity and high selectivity toward cancer cells. The H₂O₂-trigged decomposition of KAM-2 was validated, and the DNA damaging and apoptosis promoting activity attributed to the released nitrogen mustard were demonstrated. Our work unveils α-ketoamide as a new scaffold for prodrug design and may quickly inspire future developments.