The novel Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 is a potential factor for fatal illness and a tremendous concern for global public health. The COVID-19 pandemic has entered a dangerous new phase. In the context of drug discovery, the structurally-unique and chemically-diverse natural products have been valuable sources for drug leads. In this review, we report for potential candidates derived from natural sources with well-reported in vitro efficacy against SARS-CoV during the last decade. Additionally, a library of 496 phenolic metabolites was subjected to a computer-aided virtual screening against the active site of the recently reported SARS-CoV Main protease (M^pro). Analysis of physicochemical properties of these natural products has been carried out and presented for all the tested phenolic metabolites. Only three of the top candidates, viz. acetylglucopetunidin (31), isoxanthohumol (32) and ellagic acid (33), which are widely available in many edible fruits, obey both Lipinski's and Veber's rules of drug-likeness and thus possess high degrees of predicted bioavailability. These natural products are suggested as potential drug candidates for the development of anti-SARS-CoV-2 therapeutics in the near future.

Changes in gene expression cause uncontrolled cell proliferation and consequently tumor hypoxia. The tumor cells shift their metabolism to anaerobic glycolysis with a significant modification in pH. Therefore, an over expression of carbonic anhydrase IX (CA IX) genes was detected in many solid tumors. Accordingly, selective inhibition of CA IX can be a useful target for discovering novel antiproliferative agents. The present study described the synthesis of new aryl thiazolone–benzenesulfonamides 4a–j as well as their carbonic anhydrase IX inhibitory effect. All the designed derivatives were evaluated for their anti-proliferative activity against triple-negative breast cancer cell line (as MDA-MB-231) and another breast cancer cell line (MCF-7) in addition to normal breast cell line MCF-10A. Compounds 4b–c, 4e, 4g–h showed significant inhibitory effect against both cancer cell lines at concentration ranges from 1.52–6.31 μM, with a high selectivity against breast cancer cell lines ranges from 5.5 to 17.5 times. Moreover, three sulfonamides derivatives 4e, 4g and 4h showed excellent enzyme inhibition against CA IX with IC₅₀ 10.93–25.06 nM and against CA II with IC₅₀ 1.55–3.92 μM that revealed their remarkable selectivity for CA IX over CA II. Additionally, 4e was able to induce apoptosis in MDA-MB-231 with a significant increase in the annexin V-FITC percent by 22 fold as compared with control. Cellular uptake on MDA-MB-231 cell lines were carried out using HPLC method on the three active compounds (4e, 4g and 4h). On the other hand inhibition of one or more CAs present in bacteria was reported to interfere with bacterial growth. So, the new benzenesulfonamides were evaluated against their antibacterial and anti-biofilm activities. Analogues 4e, 4g and 4h exhibited significant inhibition at 50 μg mL⁻¹ concentration with 80.69%, 69.74% and 68.30% against S. aureus compared to the positive control CIP which was 99.2%, while compounds 4g and 4h showed potential anti-biofilm inhibition 79.46% and 77.52% against K. pneumonia. Furthermore, the designed compounds were docked into CA IX (human) protein (PDB ID: 5FL6) and molecular modeling studies revealed favorable binding interactions for the active inhibitors. Finally, the predictive ADMET studies showed that, compounds 4e, 4g and 4h possessed promising pharmacokinetic properties.

Lung cancer is the second most common cause of morbidity and mortality among cancer types worldwide, with non-small cell lung cancer (NSCLC) representing the majority of most cases. Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR TKIs) are among the most commonly used targeted therapy to treat NSCLC. Recent years have seen the evaluation of many synthetic EGFR TKIs, most of which showed therapeutic activity in pertinent models and were classified as first, second, and third-generation. The latest studies have concluded that their efficacy was also compromised by additional acquired mutations, including C797S. Because second- and third-generation EGFR TKIs are irreversible inhibitors, they are ineffective against C797S containing EGFR triple mutations (Del19/T790M/C797S and L858R/T790M/C797S). Therefore, there is an urgent unmet medical need to develop next-generation EGFR TKIs that selectively inhibit EGFR triple mutations via a non-irreversible mechanism. This review covers the fourth-generation EGFR-TKIs' most recent design with their essential binding interactions, the clinical difficulties, and the potential outcomes of treating patients with EGFR mutation C797S resistant to third-generation EGFR-TKIs was also discussed. Moreover, the utilization of various therapeutic strategies, including multi-targeting drugs and combination therapies, has also been reviewed.

Design of 2-phenylquinazolin-4(3H)one-trihydroxyphenyl Schiff base conjugates as COVID-19 therapy.