Cationic biaryl 1,2,3-triazolyl peptidomimetic amphiphiles targeting Clostridioides (Clostridium) difficile: Synthesis, antibacterial evaluation and an in vivo C. difficile infection model
Authors
Andrew J. Tague
Papanin Putsathit, Edith Cowan UniversityFollow
Melanie L. Hutton
Katherine A. Hammer
Steven M. Wales
Daniel R. Knight
Thomas V. Riley, Edith Cowan UniversityFollow
Dena Lyras
Paul A. Keller
Stephen G. Pyne
Document Type
Journal Article
Publication Title
European Journal of Medicinal Chemistry
Publisher
Elsevier Masson SAS
School
School of Medical and Health Sciences
RAS ID
29062
Abstract
Clostridioides (formerly Clostridium) difficile is a Gram-positive anaerobic bacterial pathogen that causes severe gastrointestinal infection in humans. The current chemotherapeutic options are vastly inadequate, expensive and limited; this results in an exorbitant medical and financial burden. New, inexpensive chemotherapeutic treatments for C. difficile infection with improved efficacy are urgently needed. A streamlined synthetic pathway was developed to allow access to 38 novel mono- and di-cationic biaryl 1,2,3-triazolyl peptidomimetics with increased synthetic efficiency, aqueous solubility and enhanced antibacterial efficacy. The monocationic arginine derivative 28 was identified as a potent, Gram-positive selective antibacterial with MIC values of 4 μg/mL against methicillin-resistant Staphylococcus aureus and 8 μg/mL against C. difficile. Furthermore, the dicationic bis-triazole analogue 50 was found to exhibit broad-spectrum activity with substantial Gram-negative efficacy against Acinetobacter baumannii (8 μg/mL), Pseudomonas aeruginosa (8 μg/mL) and Klebsiella pneumoniae (16 μg/mL); additionally, compound 50 displayed reduced haemolytic activity ( < 13%) in an in vitro haemolysis assay. Membrane-disruption assays were conducted on selected derivatives to confirm the membrane-active mechanism of action inherent to the synthesized amphiphilic compounds. A comparative solubility assay was developed and utilized to optimize the aqueous solubility of the compounds for in vivo studies. The biaryl peptidomimetics 28 and 67 were found to exhibit significant efficacy in an in vivo murine model of C. difficile infection by reducing the severity and slowing the onset of disease. © 2019 Elsevier Masson SAS
DOI
10.1016/j.ejmech.2019.02.068
Access Rights
subscription content
Comments
Tague, A. J., Putsathit, P., Hutton, M. L., Hammer, K. A., Wales, S. M., Knight, D. R., . . . Pyne, S. G. (2019). Cationic biaryl 1,2,3-triazolyl peptidomimetic amphiphiles targeting clostridioides (clostridium) difficile: Synthesis, antibacterial evaluation and an in vivo C. difficile infection model. European Journal of Medicinal Chemistry, , 203-224. https://doi.org/10.1016/j.ejmech.2019.02.068