Structure-Based Optimization of 1,2,4-Triazole-3-Thione Derivatives: Improving Inhibition of NDM-/VIM-Type Metallo-beta-Lactamases and Synergistic Activity on Resistant Bacteria.
Bersani, M., Failla, M., Vascon, F., Gianquinto, E., Bertarini, L., Baroni, M., Cruciani, G., Verdirosa, F., Sannio, F., Docquier, J.D., Cendron, L., Spyrakis, F., Lazzarato, L., Tondi, D.(2023) Pharmaceuticals (Basel) 16
- PubMed: 38139809 
- DOI: https://doi.org/10.3390/ph16121682
- Primary Citation of Related Structures:  
8B1W, 8B1Z, 8B20 - PubMed Abstract: 
The worldwide emergence and dissemination of Gram-negative bacteria expressing metallo-β-lactamases (MBLs) menace the efficacy of all β-lactam antibiotics, including carbapenems, a last-line treatment usually restricted to severe pneumonia and urinary tract infections. Nonetheless, no MBL inhibitor is yet available in therapy. We previously identified a series of 1,2,4-triazole-3-thione derivatives acting as micromolar inhibitors of MBLs in vitro, but devoid of synergistic activity in microbiological assays. Here, via a multidisciplinary approach, including molecular modelling, synthesis, enzymology, microbiology, and X-ray crystallography, we optimized this series of compounds and identified low micromolar inhibitors active against clinically relevant MBLs (NDM-1- and VIM-type). The best inhibitors increased, to a certain extent, the susceptibility of NDM-1- and VIM-4-producing clinical isolates to meropenem. X-ray structures of three selected inhibitors in complex with NDM-1 elucidated molecular recognition at the base of potency improvement, confirmed in silico predicted orientation, and will guide further development steps.
Organizational Affiliation: 
Department of Drug Science and Technology, University of Turin, Via Pietro Giuria 9, 10125 Turin, Italy.