title: Discovery of a small-molecule inhibitor and cellular probe of Keap1-Nrf2 protein-protein interaction.
abstract: A high-throughput screen (HTS) of the MLPCN library using a homogenous fluorescence polarization assay identified a small molecule as a first-in-class direct inhibitor of Keap1-Nrf2 protein-protein interaction. The HTS hit has three chiral centers; a combination of flash and chiral chromatographic separation demonstrated that Keap1-binding activity resides predominantly in one stereoisomer (SRS)-5 designated as ML334 (LH601A), which is at least 100× more potent than the other stereoisomers. The stereochemistry of the four cis isomers was assigned using X-ray crystallography and confirmed using stereospecific synthesis. (SRS)-5 is functionally active in both an ARE gene reporter assay and an Nrf2 nuclear translocation assay. The stereospecific nature of binding between (SRS)-5 and Keap1 as well as the preliminary but tractable structure-activity relationships support its use as a lead for our ongoing optimization.
authors.affiliation: Department of Medicinal Chemistry, Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, NJ 08854, USA. LongHu@rutgers.edu
authors.forename: Longqin
authors.initials: L
authors.lastname: Hu
authors.forename: Sadagopan
authors.initials: S
authors.lastname: Magesh
authors.forename: Lin
authors.initials: L
authors.lastname: Chen
authors.forename: Lili
authors.initials: L
authors.lastname: Wang
authors.forename: Timothy A
authors.initials: TA
authors.lastname: Lewis
authors.forename: Yu
authors.initials: Y
authors.lastname: Chen
authors.forename: Carol
authors.initials: C
authors.lastname: Khodier
authors.forename: Daigo
authors.initials: D
authors.lastname: Inoyama
authors.forename: Lesa J
authors.initials: LJ
authors.lastname: Beamer
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Emge
authors.forename: Jian
authors.initials: J
authors.lastname: Shen
authors.forename: John E
authors.initials: JE
authors.lastname: Kerrigan
authors.forename: Ah-Ng Tony
authors.initials: AN
authors.lastname: Kong
authors.forename: Sivaraman
authors.initials: S
authors.lastname: Dandapani
authors.forename: Michelle
authors.initials: M
authors.lastname: Palmer
authors.forename: Stuart L
authors.initials: SL
authors.lastname: Schreiber
authors.forename: Benito
authors.initials: B
authors.lastname: Munoz
mesh_terms: D018360:Crystallography, X-Ray; D004305:Dose-Response Relationship, Drug; D055808:Drug Discovery; D005454:Fluorescence Polarization; D057166:High-Throughput Screening Assays; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D007546:Isoquinolines / Q000737:chemistry / Q000494:pharmacology*; D000072019:Kelch-Like ECH-Associated Protein 1; D008958:Models, Molecular; D057054:Molecular Imaging; D015335:Molecular Probes / Q000737:chemistry / Q000494:pharmacology*; D015394:Molecular Structure; D051267:NF-E2-Related Factor 2 / Q000378:metabolism*; D010797:Phthalimides / Q000737:chemistry / Q000494:pharmacology*; D011485:Protein Binding / Q000187:drug effects; D054852:Small Molecule Libraries / Q000737:chemistry / Q000494:pharmacology*; D013329:Structure-Activity Relationship
chemical_list: D047908:Intracellular Signaling Peptides and Proteins; D007546:Isoquinolines; C431364:KEAP1 protein, human; D000072019:Kelch-Like ECH-Associated Protein 1; C000605626:LH601A; D015335:Molecular Probes; D051267:NF-E2-Related Factor 2; C495635:NFE2L2 protein, human; D010797:Phthalimides; D054852:Small Molecule Libraries
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