New 1H-1,2,4-Triazolyl Derivatives as Antimicrobial Agents.

New 1H-1,2,4-triazolyl derivatives were synthesized, and six of them were selected based on docking prediction for the investigation of their antimicrobial activity against five bacterial and eight fungal strains. All compounds demonstrated antibacterial activity with MIC lower than that of the ampicillin and chloramphenicol. In general, the most sensitive bacteria appeared to be P. fluorescens, while the plant pathogen X. campestris was the most resistant. The antifungal activity of the compounds was much better than the antibacterial activity. All compounds were more potent (6 to 45 times) than reference drugs ketoconazole and bifonazole with the best activity achieved by compound 4 a. A. versicolor, A. ochraceus, A.niger, and T.viride showed the highest sensitivity to compound 4 b, while, T. viride, P. funiculosum, and P.ochrochloron showed good sensitivity to compound 4 a. Molecular docking studies suggest that the probable mechanism of antibacterial activity involves the inhibition of the MurB enzyme of E. coli, while CYP51 of C. albicans appears to be involved in the mechanism of antifungal activity. It is worth mentioning that none of the tested compounds violated Lipinski's rule of five.

The Synthesis of Triazolium Salts as Antifungal Agents: A Biological and In Silico Evaluation.

The control of fungal pathogens is increasingly difficult due to the limited number of effective drugs available for antifungal therapy. In addition, both humans and fungi are eukaryotic organisms; antifungal drugs may have significant toxicity due to the inhibition of related human targets. Furthermore, another problem is increased incidents of fungal resistance to azoles, such as fluconazole, ketoconazole, voriconazole, etc. Thus, the interest in developing new azoles with an extended spectrum of activity still attracts the interest of the scientific community. Herein, we report the synthesis of a series of triazolium salts, an evaluation of their antifungal activity, and docking studies. Ketoconazole and bifonazole were used as reference drugs. All compounds showed good antifungal activity with MIC/MFC in the range of 0.0003 to 0.2/0.0006-0.4 mg/mL. Compound 19 exhibited the best activity among all tested with MIC/MFC in the range of 0.009 to 0.037 mg/mL and 0.0125-0.05 mg/mL, respectively. All compounds appeared to be more potent than both reference drugs. The docking studies are in accordance with experimental results.

Chemical Composition and Assessment of Antimicrobial Activity of Lavender Essential Oil and Some By-Products.

The producers of essential oils from the Republic of Moldova care about the quality of their products and at the same time, try to capitalize on the waste from processing. The purpose of the present study was to analyze the chemical composition of lavender (Lavanda angustifolia L.) essential oil and some by-products derived from its production (residual water, residual herbs), as well as to assess their "in vitro" antimicrobial activity. The gas chromatography-mass spectrometry analysis of essential oils produced by seven industrial manufacturers led to the identification of 41 constituents that meant 96.80-99.79% of the total. The main constituents are monoterpenes (84.08-92.55%), followed by sesquiterpenes (3.30-13.45%), and some aliphatic compounds (1.42-3.90%). The high-performance liquid chromatography analysis allowed the quantification of known triterpenes, ursolic, and oleanolic acids, in freshly dried lavender plants and in the residual by-products after hydrodistillation of the essential oil. The lavender essential oil showed good antibacterial activity against Bacillus subtilis, Pseudomonas fluorescens, Xanthomonas campestris, Erwinia carotovora at 300 µg/mL concentration, and Erwinia amylovora, Candida utilis at 150 µg/mL concentration, respectively. Lavender plant material but also the residual water and ethanolic extracts from the solid waste residue showed high antimicrobial activity against Aspergillus niger, Alternaria alternata, Penicillium chrysogenum, Bacillus sp., and Pseudomonas aeroginosa strains, at 0.75-6.0 µg/mL, 0.08-0.125 µg/mL, and 0.05-4.0 µg/mL, respectively.

Novel vic-dioximes: synthesis, structure characterization, and antimicrobial activity evaluation.

The vic-dioximes are compounds with various industrial uses and scientific applications. Many coordination compounds have been synthesized based on vic-dioximes. This study presents the synthesis and full characterization of two vic-dioximes based on dichloroglyoxime, p-aminobenzoic acid, and p-aminotoluene. Their structures were proved by IR, 1H, 13C and 15N NMR spectral analysis, and single crystal X-ray diffraction. One of the reported vic-dioximes, bis(di-p-aminotoluene)glyoxime mono-p-aminotoluene trihydrate showed good to moderate antimicrobial activity against both nonpathogenic gram-positive and gram-negative bacteria (Bacillus subtilis and Pseudomonas fluorescens), phytopathogenic (Xanthomonas campestris, Erwinia amylovora, E. carotovora) and the fungi (Candida utilis and Saccharomyces cerevisiae) at MIC - 70-150 µg/mL.

New vinyl-1,2,4-triazole derivatives as antimicrobial agents: Synthesis, biological evaluation and molecular docking studies.

1,2,4-Triazole is a very important scaffold in medicinal chemistry due to the wide spectrum of biological activities and mainly antifungal activity of 1,2,4-triazole derivatives. The main mechanism of antifungal action of the latter is inhibition of 14-alpha-demethylase enzyme (CYP51). The current study presents synthesis and evaluation of eight triazole derivatives for their antimicrobial activity. Docking studies to elucidate the mechanism of action were also performed. The designed compounds were synthesized using classical methods of organic synthesis. The in vivo evaluation of antimicrobial activity was performed by microdilution method. All tested compounds showed good antibacterial activity with MIC and MBC values ranging from 0.0002 to 0.0069 mM. Compound 2 h appeared to be the most active among all tested with MIC at 0.0002-0.0033 mM and MBC at 0.0004-0.0033 mM followed by compounds 2f and 2g. The most sensitive bacterium appeared to be Xanthomonas campestris while Erwinia amylovora was the most resistant. The evaluation of antifungal activity revealed that all compounds showed good antifungal activity with MIC values ranging from 0.02 mM to 0.52 mM and MFC from 0.03 mM to 0.52 mM better than reference drugs ketoconazole (MIC and MFC values at 0.28-1.88 mM and 0.38 mM to 2.82 mM respectively) and bifonazole (MIC and MFC values at 0.32-0.64 mM and 0.64-0.81 mM). The best antifungal activity is displayed by compound 2 h with MIC at 0.02-0.04 mM and MFC at 0.03-0.06 mM while compound 2a showed the lowest activity. The results showed that these compounds could be lead compounds in search for new potent antimicrobial agents. Docking studies confirmed experimental results.