Medicinal Chemistry - Current Issue

Malaria continues to be the primary cause of mortality worldwide, and timely recognition and prompt intervention are crucial in mitigating adverse consequences. This review article aims to examine the effectiveness and structural characteristics of quinoline-based compounds as antimalarial agents. It specifically focuses on their therapeutic effects as well as potential prospects for exploring structure-activity relationship (SAR). In addition, this study aims to identify lead compounds that can efficiently battle multidrug-resistant forms of Plasmodium falciparum and Plasmodium vivax.

A comprehensive review was conducted to evaluate the effectiveness of quinoline-based antimalarial medications in eradicating P. falciparum and P. vivax. The mechanism of action and SAR of these compounds were analyzed.

Quinoline-based antimalarials demonstrated significant effectiveness in eliminating P. falciparum parasites, particularly in regions severely impacted by malaria, including Africa and Asia. These compounds were found to exhibit tolerance and immune-modulating properties, indicating their potential for more widespread utilization. The investigation identified various new quinoline compounds with improved antimalarial activity, including metal-chloroquine complexes, diaminealkyne chloroquines, and cinnamoylated chloroquine hybrids. This study explored different mechanisms by which these compounds interact with parasites, including their ability to accumulate in the parasite’s acidic food vacuoles and disrupt heme detoxification. The derivatives demonstrated strong efficacy against chloroquine-resistant strains and yielded positive results.

Quinoline-based compounds represent a promising avenue for combating malaria due to their demonstrated efficacy against P. falciparum and P. vivax parasites. Further research on their mechanisms of action and SAR could lead to the development of more effective antimalarial medications.

Head and neck cancer (HNC) is on the rise worldwide, endangering lives and straining healthcare systems in both developing and developed nations. Despite the availability of a number of therapy options, the success rate for treating and controlling head and neck cancer remains dismal. To combat the aggressiveness and drug resistance of Epstein-Barr virus (EBV)-positive Head-Neck cancer cells, this study looks into the potential of Euphorbia tirucalli (pencil cactus) leaf extract.

The goal of this study is to identify prospective therapeutic candidates from the extract of Euphorbia tirucalli (pencil cactus) leaves, which have the ability to inhibit Epstein-Barr virus (EBV)-positive Head-Neck cancer cells.

The thirteen most important chemical components found in Euphorbia tirucalli (pencil cactus) leaves were analyzed by means of molecular modeling techniques such as Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET), Quantum Mechanics (QM) calculation, molecular docking, and molecular dynamics (MD) simulations. Using the Prediction of Activity Spectra for Substances (PASS) model, we assess the potency of these compounds. Important molecular properties such as chemical potential, electronegativity, hardness, and softness can be determined with the use of quantum chemical calculations employing HOMO-LUMO analysis. These drugs' safety and toxicological characteristics are better understood to assessments of their pharmacokinetics and ADMET. Finally, molecular dynamics simulations are employed to verify binding interactions and assess the stability of docked complexes.

The molecular docking analysis identifies ligands (01), (02), and (10) as strong competitors, with strong binding affinity for the Epstein-Barr virus (EBV)-positive Head-Neck cancer cell line. Not only do the ligands (01), (02), and (10) match the criteria for a potential new inhibitor of head-neck cancer, but they also outperform the present FDA-approved treatment.

Taraxerol, euphol, and ephorginol, three phytochemicals isolated from the leaves of the Euphorbia tirucalli (pencil cactus), have been identified as effective anti-cancer agents with the potential to serve as a foundation for novel head-neck cancer therapies, particularly those targeting the Epstein-Barr virus (EBV)-overexpressing subtype of this disease. An effective, individualized treatment plan for head-neck cancer is a long way off, but this study is a major step forward that could change the lives of patients and reduce the global burden of this disease.

It is noteworthy that a wide array of plants and nutraceuticals are effectively utilized in the treatment of various cancers, demonstrating potent effects on different cancer targets with fewer side effects. Notably, estrogen alpha has been identified as a crucial factor in breast cancer cell proliferation. Agents that can antagonize its action hold promise as potential drug leads for the treatment of breast cancer.

This study aims to discover and identify the potential inhibitors against the most influential ERα receptor by the computational approach of 134 phytochemicals from 17 medicinal plants by using in silico docking studies.

The molecular docking was performed by a genetic algorithm using the Auto Dock Vina program, and the validation of docking was also performed by using Molecular Dynamic (MD) simulation by the Desmond tool of Schrödinger molecular modeling. Drug-likeness properties and toxicity studies were conducted using SWISS PRO.

The top ten highest binding energy phytochemicals ginicidin (-10.8 kcal/mol), lemairone (-10.5 kcal/mol), ixoratannin (-10.0 kcal/mol), hydnocarpine (-9.8 kcal/mol), arabelline (-9.8 kcal/mol), acutilobine E (-9.8 kcal/mol), chaparinone (-8.9 kcal/mol), plumieride coumerate (-8.8 kcal/mol), acutilobine C (-8.7 kcal/mol), and mezerein (-8.7 kcal/mol) were taken for drug-likeness test and ADMET profile prediction with the help of web-based server SWISS ADME and protoxII. Docking's study dictated that ten phytochemical constituents showed greater binding interactions than standard tamoxifen (-6.6 kcal/mol) towards the target protein ERα. MSD study was achieved for the most active 4 phytoconstituents, and the stability of the ligand-protein complex was confirmed and showed that all the four compounds possess comparatively stable ligand-protein complexes with ERα target as compared to the tamoxifen-ERα complex.

Among the top ten phytochemicals, ginicidin (glycoside) formed a more stable complex and had greater binding affinity than standard tamoxifen with better safety profiles. Hence, this compound can be further studied for lead optimization and drug development for the treatment of breast cancer.

Carbonic anhydrase IX (CAIX) is known to be overexpressed in various tumors and plays a significant role in tumor development and progression.

A series of 3-(benzylsulfonamido)benzamides derivatives was synthesized and tested for their CAIX inhibitory activities. The two most active compounds were subjected to cytotoxicity testing against a panel of 60 cancer cell lines.

Many of the synthesized compounds successfully inhibited CAIX activities, exhibiting IC50 values in the low nanomolar range. The most potent CAIX inhibitor was compound 14, with an IC50 of 140 nM. Structure-activity relationship analysis of the synthesized compounds supported with molecular docking revealed strong coordination of sulfonamide moiety with the catalytic Zn²⁺ metal, hydrophobic interactions of the benzylsulfonamido ring with a hydrophobic pocket, and π-stacking interactions of the aryl ring with an aromatic surface. The two most active analogues (10 and 14) were further tested for their antiproliferative activities in the NCI-60 human tumor cell lines. Notably, compound 14 demonstrated potent growth inhibitory effects against several cancer cell lines.

The synthesized analogues represent a novel scaffold for the treatment of different types of cancer by targeting CAIX.