Chromenol Derivatives as Novel Antifungal Agents: Synthesis, In Silico and In Vitro Evaluation

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.

New 2,4-dihydro-1H-1,2,4-triazole-3-selones and 3,3'-di(4H-1,2,4-triazolyl)diselenides. Synthesis, biological evaluation, and in silico studies as antibacterial and fungicidal agents

The reaction of aromatic ring-substituted isoselenocyanates with 2-thiopheacetic and 4-pyridinecarboxylic acid hydrazides yielded selenosemicarbazides which were further converted into previously unknown 1,2,4-triazole-3-selones and 3,3'-di(4H-1, 2,4-triazolyl)diselenides. The structures of the obtained compounds were studied by NMR spectroscopy, IR spectroscopy, and high-resolution mass spectroscopy (HR-MS). The bactericidal and fungicidal activity of some obtained compounds was evaluated in molecular modeling studies such as docking and simulation studies. The compound 3ba was reported as the most promising compound to show robust binding energy with different antibacterial and antifungal compounds. The compounds were observed in strong hydrophilic and hydrophobic interactions and remained in stable binding conformation with the receptor enzymes. Furthermore, the interatomic interaction energies were dominated by Van der Waals and electrostatic energies indicating the formation of stable complexes.

Resin Acids as Raw Material for the Preparation of Cyclodextrin Complexes Loaded with Dehydroabietitoic Acid and Chromenol Hybrid

In this work new methods to obtain complexes from β-cyclodextrin and dehydroabietic acid with chromenol-triazol hybrid with the sizes limits of approximately 0.1-250 μm are reported. Kneading, co-evaporation and co-precipitation for the resolution of racemic 2-tert-butyl-3-(1H-1,2,4-triazol-1-yl)-2H-chromen-2-ol for obtaining micro- and nanoparticles have been optimized. In vitro dissolution studies of the synthesized compounds in phosphate buffer (pH 6.8) showed an improved dissolution rate of chromenol-triazol hybrid in the inclusion complexes compared to the free form. The obtained β-complexes of β-cyclodextrin loaded with dehydroabietitoic acid and chromenol hybrid showed good antibacterial activity with MIC and MBC values ranging from 0.72 to 44.45 μM.

Efficient selective targeting of Candida CYP51 by oxadiazole derivatives designed from plant cuminaldehyde

Candida infection represents a global threat with associated high resistance and mortality rate. Azoles such as the triazole drug fluconazole are the frontline therapy against invasive fungal infections; however, the emerging multidrug-resistant strains limit their use. Therefore, a series of novel azole UOSO1-15 derivatives were developed based on a modified natural scaffold to combat the evolved resistance mechanism and to provide improved safety and target selectivity. The antifungal screening against C. albicans and C. auris showed that UOSO10 and 12-14 compounds were the most potent derivatives. Among them, UOSO13 exhibited superior potent activity with MIC50 values of 0.5 and 0.8 μg mL-1 against C. albicans and C. auris compared to 25 and 600 μg mL-1 for fluconazole, respectively. UOSO13 displayed significant CaCYP51 enzyme inhibition activity in a concentration-dependent manner with an IC50 10-fold that of fluconazole, while exhibiting no activity against human CYP50 enzyme or toxicity to human cells. Furthermore, UOSO13 caused a significant reduction of Candida ergosterol content by 70.3% compared to a 35.6% reduction by fluconazole. Homology modeling, molecular docking, and molecular dynamics simulations of C. auris CYP51 enzyme indicated the stability and superiority of UOSO13. ADME prediction indicated that UOSO13 fulfils the drug-likeness criteria with good physicochemical properties.

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.