Challenges in the Development of a Thiol-Based Broad-Spectrum Inhibitor for Metallo-β-Lactamases

ACS Infect Dis. 2018 Mar 9;4(3):360-372. doi: 10.1021/acsinfecdis.7b00129. Epub 2017 Dec 12.


Pathogens, expressing metallo-β-lactamases (MBLs), become resistant against most β-lactam antibiotics. Besides the dragging search for new antibiotics, development of MBL inhibitors would be an alternative weapon against resistant bacterial pathogens. Inhibition of resistance enzymes could restore the antibacterial activity of β-lactams. Various approaches to MBL inhibitors are described; among others, the promising motif of a zinc coordinating thiol moiety is very popular. Nevertheless, since the first report of a thiol-based MBL inhibitor (thiomandelic acid) in 2001, no steps in development of thiol based MBL inhibitors were reported that go beyond clinical isolate testing. In this study, we report on the synthesis and biochemical characterization of thiol-based MBL inhibitors and highlight the challenges behind the development of thiol-based compounds, which exhibit good in vitro activity toward a broad spectrum of MBLs, selectivity against human off-targets, and reasonable activity against clinical isolates.

Keywords: bacterial resistance; biochemical characterization; metallo-β-lactamase inhibitor; metallo-β-lactamases; synthesis; thiol-based.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Drug Discovery / methods*
  • Sulfhydryl Compounds / chemical synthesis
  • Sulfhydryl Compounds / isolation & purification*
  • Sulfhydryl Compounds / pharmacology*
  • beta-Lactam Resistance / drug effects
  • beta-Lactamase Inhibitors / chemical synthesis
  • beta-Lactamase Inhibitors / isolation & purification*
  • beta-Lactamase Inhibitors / pharmacology*


  • Sulfhydryl Compounds
  • beta-Lactamase Inhibitors