Improving Antimicrobial Activity and Physico-Chemical Properties by Isosteric Replacement of 2-Aminothiazole with 2-Aminooxazole

Antimicrobial drug resistance is currently one of the most critical health issues. Pathogens resistant to last-resort antibiotics are increasing, and very few effective antibacterial agents have been introduced in recent years. The promising drug candidates are often discontinued in the primary stag...

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Bibliographic Details
Main Authors: Martin Juhás, Andrea Bachtíková, Daria Elżbieta Nawrot, Paulína Hatoková, Vinod Sukanth Kumar Pallabothula, Adéla Diepoltová, Ondřej Janďourek, Pavel Bárta, Klára Konečná, Pavla Paterová, Vít Šesták, Jan Zitko
Format: Article
Language:English
Published: MDPI AG 2022-05-01
Series:Pharmaceuticals
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Online Access:https://www.mdpi.com/1424-8247/15/5/580
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Summary:Antimicrobial drug resistance is currently one of the most critical health issues. Pathogens resistant to last-resort antibiotics are increasing, and very few effective antibacterial agents have been introduced in recent years. The promising drug candidates are often discontinued in the primary stages of the drug discovery pipeline due to their unspecific reactivity (PAINS), toxicity, insufficient stability, or low water solubility. In this work, we investigated a series of substituted <i>N</i>-oxazolyl- and <i>N</i>-thiazolylcarboxamides of various pyridinecarboxylic acids. Final compounds were tested against several microbial species. In general, oxazole-containing compounds showed high activity against mycobacteria, especially <i>Mycobacterium tuberculosis</i> (best MIC<sub>H37Ra</sub> = 3.13 µg/mL), including the multidrug-resistant strains. Promising activities against various bacterial and fungal strains were also observed. None of the compounds was significantly cytotoxic against the HepG2 cell line. Experimental measurement of lipophilicity parameter log k’<sub>w</sub> and water solubility (log <i>S</i>) confirmed significantly (typically two orders in logarithmic scale) increased hydrophilicity/water solubility of oxazole derivatives in comparison with their thiazole isosteres. Mycobacterial β-ketoacyl-acyl carrier protein synthase III (FabH) was suggested as a probable target by molecular docking and molecular dynamics simulations.
ISSN:1424-8247