The novel coronavirus SARS-CoV2, the causative agent of the pandemic disease COVID-19, emerged in December 2019 forcing lockdown of communities in many countries. The absence of specific drugs and vaccines, the rapid transmission of the virus, and the increasing number of deaths worldwide necessitated the discovery of new substances for anti-COVID-19 drug development. With the aid of bioinformatics and computational modelling, ninety seven antiviral secondary metabolites from fungi were docked onto five SARS-CoV2 enzymes involved in viral attachment, replication, post-translational modification, and host immunity evasion infection mechanisms followed by molecular dynamics simulation and in silico ADMET prediction (absorption, distribution, metabolism, excretion and toxicity) of the hit compounds. Thus, three fumiquinazoline alkaloids scedapin C (15), quinadoline B (19) and norquinadoline A (20), the polyketide isochaetochromin D1 (8), and the terpenoid 11a-dehydroxyisoterreulactone A (11) exhibited high binding affinities on the target proteins, papain-like protease (PLpro), chymotrypsin-like protease (3CLpro), RNA-directed RNA polymerase (RdRp), non-structural protein 15 (nsp15), and the spike binding domain to GRP78. Molecular dynamics simulation was performed to optimize the interaction and investigate the stability of the top-scoring ligands in complex with the five target proteins. All tested complexes were found to have dynamic stability. Of the five top-scoring metabolites, quinadoline B (19) was predicted to confer favorable ADMET values, high gastrointestinal absorptive probability and poor blood-brain barrier crossing capacities.

: The ongoing Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic has been proven to be more severe than the previous coronavirus outbreaks due to the virus’ high transmissibility. With the emergence of new variants, this global phenomenon took on a more dramatic turn with many countries recently experiencing higher surges of confirmed cases and deaths. On top of this, the inadequacy of effective treatment options for COVID-19 aggravated the problem. As a way to address the unavailability of target-specific viral therapeutics, computational strategies have been employed to hasten and systematize the search. The objective of this review is to provide initial data highlighting the utility of polyphenols as potential prophylaxis or treatment for COVID-19. In particular, presented here are virtually screened polyphenolic compounds which showed potential as either antagonists to viral entry and host cell recognition through binding with various receptor-binding regions of SARS-CoV-2 spike protein or as inhibitors of viral replication and post-translational modifications through binding with essential SARS-CoV-2 non-structural proteins.

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The novel coronavirus SARS-CoV2, the causative agent of the worldwide pandemic disease COVID-19, emerged in December 2019 forcing lockdown of communities in many countries. The absence of specific drugs and vaccines, the rapid transmission of the virus, and the increasing number of deaths worldwide have necessitated the need to discover substances that can be tapped for drug development. With the aid of bioinformatics and computational modelling, ninety seven secondary metabolites from fungi previously reported to exhibit antiviral properties were docked onto SARS-CoV2 enzymes involved in viral attachment, replication and post-translational mechanisms followed by <i>in silico</i> ADMET prediction (absorption, distribution, metabolism, excretion and toxicity) of the hit compounds. Thus, two fumiquinazoline alkaloids quinadoline B (<b>19</b>), scedapin C (<b>15</b>), and the polyketide isochaetochromin D1 (<b>8</b>) exhibited high binding affinities depending on the target protein. The compounds were active against the cysteine proteases, papain-like protease (PLpro) and chymotrypsin-like protease (3CLpro) which are involved in post-translational modifications, RNA-directed RNA polymerase (RdRp) which is essential in viral replication, non-structural protein 15 (nsp15) which is involved in evasion of host immunity, and the spike protein which is responsible for binding to GRP78. Quinadoline B (<b>19</b>) was predicted to confer favorable ADMET values, high gastrointestinal absorptive probability and poor blood-brain barrier crossing capacities.

Background: Electrophilic compounds bearing Michael acceptors present great promise in anticancer drug discovery. Methods: Drawing inspirations from cytotoxic Piper lactam alkaloids, twelve N-acylated butyro- and valerolactams were prepared and evaluated for antiproliferative and cytotoxic activities against the normal human umbilical vein endothelial cells (HUVEC), chronic human myeloid leukemia cells (K- 562), and Henrietta Lacks (HeLa) cells used as model cell lines. Molecular docking of bioactive derivatives was performed against tyrosine kinase. Results: Results of the MTT assay showed the crotonylated (5) and nitro-containing cinnamoyl (8) butyrolactams, and, the crotonylated (10), trifluoromethylated (13), and chlorinated (14) cinnamoyl valerolactam derivatives as the most antiproliferative against human myeloid leukemia cells. The trifluoromethylated cinnamoyl valerolactam (13) displayed the best selectivity on K-562 cells. Molecular docking studies of 13 against tyrosine kinase provided evidence as tyrosine kinase inhibitor, having comparable binding energy and receptor interaction with imatinib. Conclusion: The presence of electrophilic N-acrylic moieties contributes to the potential of a compound as inspiration to develop anti-leukemia drugs.