Potentiating 1-(2-hydroxypropyl)-2-styryl-5-nitroimidazole derivatives against antibacterial agents: Design, synthesis and biology analysis

Fatty Acid Biosynthesis: An Updated Review on KAS Inhibitors

Since the early twentieth century, with the isolation of penicillin and streptomycin in the 1940s, the modern era of anti-infective drug development has gained momentum. Due to the enormous success of early drug discovery, many infectious diseases were successfully prevented and eradicated. However, this initial hope was wrongheaded, and pathogens evolved as a significant threat to human health. Drug resistance develops as a result of natural selection's relentless pressure, necessitating the identification of new drug targets and the creation of chemotherapeutics that bypass existing drug resistance mechanisms. Fatty acid biosynthesis (FAS) is a crucial metabolic mechanism for bacteria during their growth and development. Several crucial enzymes involved in this biosynthetic pathway have been identified as potential targets for new antibacterial agents. In Escherichia coli (E. coli), this pathway has been extensively investigated. The present review focuses on progress in the development of Kas A, Kas B, and Fab H inhibitors as mono-therapeutic antibiotics.

Nitroimidazole-containing compounds and their antibacterial and antitubercular activities

Infections especially tuberculosis caused by various bacteria including mycobacteria result in millions of lives every year, but the control of bacterial infections is challenged by the limitation of effective pharmaceuticals against drug-resistant pathogens. Nitroimidazoles belong to a group of nitroheterocyclic compounds that have broad-spectrum activity against a series of organisms such as mycobacteria, anaerobic Gram-positive and Gram-negative bacteria, and some of them have already been used in clinics or under clinical trials for the treatment of infectious diseases. In this review, we made an overview of the recent advances in nitroimidazole-containing compounds with antibacterial and antitubercular activity in the recent 20 years.

Design, synthesis, and biological evaluation of chrysin derivatives as potential FabH inhibitors

New series of chrysin derivatives (4a-4t) were designed and synthesized by introducing different substituted piperazines at C-7 position. Their inhibitory effects on FabH were evaluated using two Gram-negative bacterial strains, Escherichia coli and Pseudomonas aeruginosa, and two Gram-positive bacterial strains, Bacillus subtilis and Staphylococcus aureus. To our delight, most of these compounds exhibited a dramatic increase in inhibitory potency, compared with the control positive drugs. Among them, compound 4s exhibited the most potent inhibitory activity with IC₅₀ values of 5.78 ± 0.24 μm inhibiting E. coli FabH and potent antibacterial activity against S. aureus and E. coli with MIC of 1.25 ± 0.01, 1.15 ± 0.12 μg/mL, respectively, comparing to the control positive drugs penicillin G (7.56 ± 0.30 μm). Docking simulation was performed to position compound 4s into the FabH active site, and the result showed that compound 4s could bind well with the FabH as potent FabH inhibitor.

Design, synthesis and biological evaluation of metronidazole-thiazole derivatives as antibacterial inhibitors

A series of metronidazole-thiazole derivatives has been designed, synthesized and evaluated as potential antibacterial inhibitors. All the synthesized compounds were determined by elemental analysis, 1H NMR and MS. They were also tested for antibacterial activity against Escherichia coli, Bacillus thuringiensis, Bacillus subtilis and Pseudomonas aeruginosa as well as for the inhibition to FabH. The results showed that compound 5e exhibited the most potent inhibitory activity against E. coli FabH with IC50 of 4.9μM. Molecular modeling simulation studies were performed in order to predict the biological activity of proposed compounds. Toxicity assay of compounds 5a, 5b, 5d, 5e, 5g and 5i showed that they were noncytotoxic against human macrophage. The results revealed that these compounds offered remarkable viability.

Schiff's base derivatives bearing nitroimidazole and quinoline nuclei: new class of anticancer agents and potential EGFR tyrosine kinase inhibitors

New Schiff's base derivatives 5a-j have been synthesized by reaction between 2-phenoxyquinoline-3-carbaldehydes 3a-j and 2-(2-methyl-5-nitro-1H-imidazol-1-yl)acetohydrazide 4 in presence of nickel(II) nitrate as a catalyst in ethanol under reflux in good yield (78-92%). All compounds were tested for anticancer and inhibition of EGFR. Of the compounds studied, majority of the compounds showed effective antiproliferation and inhibition of EGFR and HER-2 activities. Compound 5h showed most effective inhibition (IC50=0.12±0.05 μM) by binding in to the active pocket of EGFR receptor with minimum binding energy (ΔGb=-58.3691 kcal/mol). The binding was stabilized by two hydrogen bonds, two π-cation and one π-sigma interactions. Compound 5d showed most effective inhibition (IC50=0.37±0.04 μM).