ETD

• fragment based drug desgin
• keap1
• oxidative stress
• ppi inhibitors

Under basal conditions low levels of reactive oxygen species (ROS) are produced as byproducts of metabolic processes. However, the production of ROS can become uncontrolled, leading to oxidative stress, which underlies many pathologies such as chronic kidney disease (CKD), non-alcoholic steatohepatitis (NASH), multiple sclerosis (MS), Alzheimer's disease, rheumatoid arthritis and ischemic stroke, among many others. The Kelch-like ECH-associated protein 1 (Keap1) interacts with the nuclear factor erythroid 2-related factor 2 (Nrf2), activating a cellular pathway with a key role in maintaining low ROS concentrations.
Thus, targeting Keap1-Nrf2 PPI interactions is a promising therapeutic strategy against oxidative stress and inflammation-based pathologies.
An early strategy was to develop covalent Keap1 inhibitors, which, however, showed several off-target effects. Hence, most of them haven’t been approved yet.
A different approach is targeting Nrf2 pathway with non-covalent Keap1-Nrf2 protein-protein interaction (PPI) inhibitors. They bind to Keap1’s Kelch domain disrupting Keap1-Nrf2 interaction, promoting Nrf2 nuclear translocation. Although a lot of these compounds have shown to be active in cells and in animal disease models, many of them have some disadvantages, such as low permeability, poor metabolic stability and bad oral absorption. As of today, no Keap1-Nrf2 PPI inhibitor has yet reached clinical trials.
Thus, my project’s aim was to develop novel high-affinity, cell-permeable and in vivo active Keap1-Nrf2 PPI inhibitors, taking advantage of fragment-based drug design (FBDD) as a promising strategy for drug development. In this thesis, 7 pyridone-like and benzotriazole-like compounds have been synthesized. Among them 2 compounds were previously developed by other members of the group and they were synthesized again for further evaluation. These were then tested in a fluorescence polarization assay, where the compounds displayed inhibition constants in the low to sub-nanomolar range. Furthermore, they were docked into Keap1’s Kelch domain in order to investigate their binding modes.