Tunable Cysteine-Targeting Electrophilic Heteroaromatic Warheads Induce Ferroptosis

J Med Chem. 2022 Sep 8;65(17):11788-11817. doi: 10.1021/acs.jmedchem.2c00909. Epub 2022 Aug 19.

Abstract

Once considered potential liabilities, the modern era witnesses a renaissance of interest in covalent inhibitors in drug discovery. The available toolbox of electrophilic warheads is limited by constraints on tuning reactivity and selectivity. Following our work on a class of ferroptotic agents termed CETZOLEs, we discovered new tunable heterocyclic electrophiles which are capable of inducing ferroptosis. The biological evaluation demonstrated that thiazoles with an alkyne electrophile at the 2-position selectively induce ferroptosis with high potency. Density functional theory calculations and NMR kinetic studies demonstrated the ability of our heterocycles to undergo thiol addition, an apparent prerequisite for cytotoxicity. Chemoproteomic analysis indicated several potential targets, the most prominent among them being GPX4 protein. These results were further validated by western blot analysis and the cellular thermal shift assay. Incorporation of these heterocycles into appropriate pharmacophores generated highly cytotoxic agents such as the analogue BCP-T.A, with low nM IC50 values in ferroptosis-sensitive cell lines.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, N.I.H., Intramural

MeSH terms

  • Cysteine* / chemistry
  • Drug Discovery
  • Ferroptosis*
  • Kinetics
  • Sulfhydryl Compounds / chemistry

Substances

  • Sulfhydryl Compounds
  • Cysteine