Potent Inhibition of SARS-CoV-2 nsp14 N 7-Methyltransferase by Sulfonamide-Based Bisubstrate Analogues

J Med Chem. 2022 Apr 28;65(8):6231-6249. doi: 10.1021/acs.jmedchem.2c00120. Epub 2022 Apr 19.

Abstract

Enzymes involved in RNA capping of SARS-CoV-2 are essential for the stability of viral RNA, translation of mRNAs, and virus evasion from innate immunity, making them attractive targets for antiviral agents. In this work, we focused on the design and synthesis of nucleoside-derived inhibitors against the SARS-CoV-2 nsp14 (N7-guanine)-methyltransferase (N7-MTase) that catalyzes the transfer of the methyl group from the S-adenosyl-l-methionine (SAM) cofactor to the N7-guanosine cap. Seven compounds out of 39 SAM analogues showed remarkable double-digit nanomolar inhibitory activity against the N7-MTase nsp14. Molecular docking supported the structure-activity relationships of these inhibitors and a bisubstrate-based mechanism of action. The three most potent inhibitors significantly stabilized nsp14 (ΔTm ≈ 11 °C), and the best inhibitor demonstrated high selectivity for nsp14 over human RNA N7-MTase.

MeSH terms

  • COVID-19 Drug Treatment*
  • COVID-19* / virology
  • Exoribonucleases / antagonists & inhibitors
  • Exoribonucleases / chemistry
  • Humans
  • Methyltransferases
  • Molecular Docking Simulation
  • RNA, Viral / genetics
  • S-Adenosylmethionine
  • SARS-CoV-2* / drug effects
  • SARS-CoV-2* / enzymology
  • Sulfonamides / pharmacology
  • Viral Nonstructural Proteins / antagonists & inhibitors
  • Viral Nonstructural Proteins / chemistry

Substances

  • RNA, Viral
  • Sulfonamides
  • Viral Nonstructural Proteins
  • S-Adenosylmethionine
  • Methyltransferases
  • Exoribonucleases
  • NSP14 protein, SARS-CoV-2