Structure based design, synthesis, and biological evaluation of imidazole derivatives targeting dihydropteroate synthase enzyme

Design, Synthesis, DFT, docking Studies, and antimicrobial evaluation of novel benzimidazole containing sulphonamide derivatives

In silico approaches have been employed to design a new series of benzimidazole-containing sulphonamide derivatives and qualified compounds have been synthesized to analyze their potential as antimicrobial agents. Antibacterial screening of all synthesized compounds was done using the broth microdilution method against several human pathogenic bacteria, viz. Gram-positive bacteria [B. cerus (NCIN-2156), B. subtilis (ATCC-6051), S. aureus (NCIM-2079)] and Gram-negative bacteria [P. aeruginosa (NCIM-2036), E. coli (NCIM-2065), and a drug-resistant strain of E. coli (U-621)], and the compounds presented admirable MIC values, ranging between 100-1.56 µg/mL. The combinatorial analysis showed the magnificent inhibitory efficiency of the tested compounds, acquired equipotent to ten-fold more potency compared to original MIC values. An immense synergistic effect was exhibited by the compounds during combination studies with reference drugs chloramphenicol and sulfamethoxazole was presented as fractional inhibitory concentration (∑FIC). Enzyme inhibition studies of all synthesized compounds were done by using peptidyl transferase and dihydropteroate synthase enzymes isolated from E. coli and S. aureus and each of the compound presented the admirable IC50 values, where the lead compound 3 bound to peptidyl transferase (of S. aureus with IC50 363.51 ± 2.54 µM and E. coli IC50 1.04 ± 0.08 µM) & dihydropteroate synthase (of S. aureus IC50 3.51 ± 0.82 µM and E. coli IC50 2.77 ± 0.65 µM), might account for the antimicrobial effect, exhibited excellent inhibition potential. Antifungal screening was also performed employing food poisoning methods against several pathogenic fungal species, viz A. flavus, F. oxysporum, A. niger, and A. brassicae. The obtained result indicated that few compounds can prove to be a potent drug regimen against dreaded MDR strains of microbes. Structural activity relationship (SAR) analysis and docking studies reveal that the presence of electron-withdrawing, polar, and more lipophilic substituents positively favor the antibacterial activity, whereas, electron-withdrawing, more polar, and hydrophilic substituents favor the antifungal activities. A robust coherence has been found in in-silico and in-vitro biological screening results of the compounds.

Exploring the Recent Pioneering Developments of Small Molecules in Antimalarial Drug Armamentarium: A Chemistry Prospective Appraisal

Malaria is a very destructive and lethal parasitic disease that causes significant mortality worldwide, resulting in the loss of millions of lives annually. It is an infectious disease transmitted by mosquitoes, which is caused by different species of the parasite protozoan belonging to the genus Plasmodium. The uncontrolled intake of antimalarial drugs often employed in clinical settings has resulted in the emergence of numerous strains of plasmodium that are resistant to these drugs, including multidrug-resistant strains. This resistance significantly diminishes the effectiveness of many primary drugs used in the treatment of malaria. Hence, there is an urgent need for developing unique classes of antimalarial drugs that function with distinct mechanisms of action. In this context, the design and development of hybrid compounds that combine pharmacophoric properties from different lead molecules into a single unit gives a unique perspective towards further development of malaria drugs in the next generation. In recent years, the field of medicinal chemistry has made significant efforts resulting in the discovery and synthesis of numerous small novel compounds that exhibit potent antimalarial properties, while also demonstrating reduced toxicity and desirable efficacy. In light of this, we have reviewed the progress of hybrid antimalarial agents from 2021 up to the present. This manuscript presents a comprehensive overview of the latest advancements in the medicinal chemistry pertaining to small molecules, with a specific focus on their potential as antimalarial agents. As possible antimalarial drugs that might target both the dual stage and multi-stage stages of the parasite life cycle, these small hybrid molecules have been studied. This review explores a variety of physiologically active compounds that have been described in the literature in order to lay a strong foundation for the logical design and eventual identification of antimalarial drugs based on lead frameworks.

Novel 4-nitroimidazole analogues: synthesis, in vitro biological evaluation, in silico studies, and molecular dynamics simulation

A new series of 4-nitroimidazole bearing aryl piperazines 7-16, tetrazole 17 and 1,3,4-thiadiazole 18 derivatives was synthesized. All derivatives were screened for their anticancer activity against eight diverse human cancer cell lines (Capan-1, HCT-116, LN229, NCI-H460, DND-41, HL-60, K562, and Z138). Compound 17 proved the most potent compound of the series inhibiting proliferation of most of the selected human cancer cell lines with IC50 values in the low micromolar range. In addition, compound 11 exhibited IC50 values ranging 8.60-64.0 μM against a selection of cancer cell lines. These findings suggest that derivative 17 can potentially be a new lead compound for further development of novel antiproliferative agents. Additionally, 17-18 were assessed for their antibacterial and antituberculosis activity. Derivatives 17 and 18 were the most potent compounds of this series against both Staphylococcus aureus strain Wichita and a methicillin resistant strain of S. aureus (MRSA), as well as against Mycobacterium tuberculosis strain mc26230. The antiviral activity of 7-18 was also evaluated against diverse viruses, but no activity was detected. The docking study of compound 17 with putative protein targets in acute myeloid leukemia had been studied. Furthermore, the molecular dynamics simulation of 17 and 18 had been investigated.

An Overview of the Biological Evaluation of Selected Nitrogen-Containing Heterocycle Medicinal Chemistry Compounds

Heterocyclic compounds are a class of compounds of natural origin with favorable properties and hence have major pharmaceutical significance. They have an exceptional adroitness favoring their use as diverse smart biomimetics, in addition to possessing an active pharmacophore in a complex structure. This has made them an indispensable motif in the drug discovery field. Heterocyclic compounds are usually classified according to the ring size, type, and the number of heteroatoms present in the ring. Among different heterocyclic ring systems, nitrogen heterocyclic compounds are more abundant in nature. They also have considerable pharmacological significance. This review highlights recent pioneering studies in the biological assessment of nitrogen-containing compounds, namely: triazoles, tetrazoles, imidazole/benzimidazoles, pyrimidines, and quinolines. It explores publications between April 2020 and February 2022 and will benefit researchers in medicinal chemistry and pharmacology. The present work is organized based on the size of the heterocyclic ring.

Imidazole as a Promising Medicinal Scaffold: Current Status and Future Direction

Various imidazole-containing compounds have been tested for their medical usefulness in clinical trials for several disease conditions. The rapid expansion of imidazole-based medicinal chemistry suggests the promising and potential therapeutic values of imidazole-derived compounds for treating incurable diseases. Imidazole core scaffold contains three carbon atoms, and two nitrogen with electronic-rich characteristics that are responsible for readily binding with a variety of enzymes, proteins, and receptors compared to the other heterocyclic rings. Herein, we provide a thorough overview of the current research status of imidazole-based compounds with a wide variety of biological activities including anti-cancer, anti-microbial, anti-inflammatory and their potential mechanisms including topoisomerase IIR catalytic inhibition, focal adhesion kinase (FAK) inhibition, c-MYC G-quadruplex DNA stabilization, and aurora kinase inhibition. Additionally, a great interest was reported in the discovery of novel imidazole compounds with anti-microbial properties that break DNA double-strand helix and inhibit protein kinase. Moreover, anti-inflammatory mechanisms of imidazole derivatives include inhibition of COX-2 enzyme, inhibit neutrophils degranulation, and generation of reactive oxygen species. This systemic review helps to design and discover more potent and efficacious imidazole compounds based on the reported derivatives, their ADME profiles, and bioavailability scores that together aid to advance this class of compounds.