Structure-based optimization of a macrocyclic inhibitor of the Keap1-Nrf2 protein-protein interaction

• Activation of the transcription factor Nrf2 by inhibition of the interaction with its negative regulator Keap1 constitutes a potential opportunity for the treatment of oxidative stress related disease. Although highly potent inhibitors of the Keap1­–Nrf2 protein-protein interaction (PPI) have been reported, these compounds are based on a few reoccurring scaffolds. Here, we report a novel, structurally unique series of double-digit nM Keap1 inhibitors obtained by optimization of a natural product-derived macrocyclic lead. Exploration of the structure-activity relationship, followed by structure-based design led to a 100-fold improvement in inhibitory potency compared to the starting point. The macrocyclic core positions the pharmacophores of the inhibitors suitably for productive interactions with key residues of Keap1, including R415 and R483; both of which contribute to the highly polar nature of the binding site for Nrf2. In addition, we discovered that minor, ligand-induced reorganizations of these two arginine residues are accompanied by major differences in binding affinity between compounds in the series.

Subject headings

NATURVETENSKAP  -- Biologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences (hsv//eng)

NATURVETENSKAP  -- Kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences (hsv//eng)

Publication and Content Type

vet (subject category)

ovr (subject category)