Keap1-Nrf2-IN-9 (compound 11) is a potent Keap1-Nrf2 PPI ( Keap1-Nrf2 protein−protein interaction) inhibitor with an IC 50 of 0.575 µM. Keap1-Nrf2-IN-9 increases the expression of Nrf2 target genes including heme oxygenase 1 (Hmox1), glutathione S-transferase P (GstP), and glutamate-cysteine ligase catalytic (Gclc) and modulatory (Gclm) subunits. Keap1-Nrf2-IN-9 shows not cytotoxic activity in ARPE19 cells.