OBJECTIVE: Aim of the present study was to analyse the molecular interaction of nitrogen heterocyclic based drugs (hydroxychloroquine, remdesivir and lomefloxacin) with various SARSCoV- 2 proteins (RdRp, PLPro, Mpro and spike proteins) using a molecular docking approach.
METHODS: We have performed docking study using PyRx software, and Discovery Studio Visualizer was used to visualise the molecular interactions. The designed nitrogen heterocyclic analogues were checked for Lipinski's rule of five, Veber's Law and Adsorption, Distribution, Metabolism, and Excretion (ADME) threshold. After obtaining the docking results of existing nitrogen heterocyclic drugs, we modified the selected drugs to get molecules with better affinity against SARS-CoV-2.
RESULTS: Hydroxychloroquine bound to RdRp, spike protein, PLPro and Mpro at -5.2, -5.1, -6.7 and -6.0 kcal/mol, while remdesivir bound to RdRp, spike protein, PLPro, and Mpro at -6.1, -6.9, -6.4 and -6.9 kcal/mol, respectively. Lomefloxacin bound to RdRp, spike protein, PLPro and Pro at -6.4, -6.6, -7.2 and -6.9 kcal/mol. ADME studies of all these compounds indicated lipophilicity and high gastro intestine absorbability. The modified drug structures possess better binding efficacy towards at least one target than their parent compounds.
CONCLUSION: The outcome reveals that the designed nitrogen heterocyclics could contribute to developing the potent inhibitory drug SARS-CoV-2 with strong multi-targeted inhibition ability and reactivity.
METHODS: A literature search was performed for the screening of natural and derived bio-active compounds which showed potent antiviral activity against coronaviruses using published articles, patents, clinical trials website (https://clinicaltrials.gov/) and web databases (PubMed, SCI Finder, Science Direct, and Google Scholar).
RESULTS: Through the screening for natural products with antiviral activities against different types of the human coronavirus, extracts of Lycoris radiata (L'Hér.), Gentiana scabra Bunge, Dioscorea batatas Decne., Cassia tora L., Taxillus chinensis (DC.), Cibotium barometz L. and Echinacea purpurea L. showed a promising effect against SARS-CoV. Out of the listed compound Lycorine, emetine dihydrochloride hydrate, pristimerin, harmine, conessine, berbamine, 4`-hydroxychalcone, papaverine, mycophenolic acid, mycophenolate mofetil, monensin sodium, cycloheximide, oligomycin and valinomycin show potent activity against human coronaviruses. Additionally, it is worth noting that some compounds have already moved into clinical trials for their activity against COVID-19 including fingolimod, methylprednisolone, chloroquine, tetrandrine and tocilizumab.
CONCLUSION: Natural compounds and their derivatives could be used for developing potent therapeutics with significant activity against SARS-COV-2, providing a promising frontline in the fighting against COVID-19.