Nitrothiophene carboxamides, a novel narrow spectrum antibacterial series: Mechanism of action and Efficacy

Sci Rep. 2018 May 8;8(1):7263. doi: 10.1038/s41598-018-25407-7.


The mechanism of efflux is a tour-de-force in the bacterial armoury that has thwarted the development of novel antibiotics. We report the discovery of a novel chemical series with potent antibacterial properties that was engineered to overcome efflux liability. Compounds liable to efflux specifically via the Resistance Nodulation and cell Division (RND) pump, AcrAB-TolC were chosen for a hit to lead progression. Using structure-based design, the compounds were optimised to lose their binding to the efflux pump, thereby making them potent on wild-type bacteria. We discovered these compounds to be pro-drugs that require activation in E. coli by specific bacterial nitroreductases NfsA and NfsB. Hit to lead chemistry led to the generation of compounds that were potent on wild-type and multi-drug resistant clinical isolates of E. coli, Shigella spp., and Salmonella spp. These compounds are bactericidal and efficacious in a mouse thigh infection model.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Bacterial Agents / chemical synthesis
  • Anti-Bacterial Agents / chemistry*
  • Anti-Bacterial Agents / pharmacology
  • Cell Division / drug effects
  • Drug Resistance, Multiple, Bacterial / drug effects*
  • Drug Resistance, Multiple, Bacterial / genetics
  • Escherichia coli Proteins / chemistry*
  • Escherichia coli Proteins / drug effects
  • Humans
  • Mice
  • Microbial Sensitivity Tests
  • Prodrugs / chemical synthesis
  • Prodrugs / chemistry*
  • Prodrugs / pharmacology
  • Protein Conformation / drug effects
  • Salmonella / chemistry
  • Salmonella / drug effects
  • Salmonella / pathogenicity
  • Shigella / chemistry
  • Shigella / drug effects
  • Shigella / pathogenicity
  • Thiophenes / chemical synthesis
  • Thiophenes / chemistry*
  • Thiophenes / pharmacology


  • Anti-Bacterial Agents
  • Escherichia coli Proteins
  • Prodrugs
  • Thiophenes