Virtual design and screening of new (+)-catechin derivates N- and/or S-heterocyclic fragment for anti-malarial and anti-SARS-CoV-2 activities by In silico simulation

Hemisynthesis makes it possible to improve the activity or reduce the toxicity of a biocompound by modifying or adding peripheral groups. Catechin present in different plant species was known for its moderate anti-malarial and anti-SARS-CoV-2 activities. The aim of this work was focused on the identification of new compounds with potential anti-SARS-CoV-2 and/or anti-malarial activities, evaluated through In silico simulation. A polyphenol pharmacophore model, based on (+)-catechin (1) was virtually constructed using previously reported inhibitors. N- and/or S-heterocyclic fragments were inserted on the backbone of (+)-catechin and 12 pharmacophore hypotheses were studied. This study targeted 3 proteins biologically responsible for SARS-CoV-2 (PDB ID: 7JYC, 6M0J, and 6HZD) and one protein responsible for malaria (PDB ID: 3SRJ). Molecular docking had shown that the new catechin-aldehyde candidates have good Ligand-Protein affinity in terms of free energy compared to the study reference Narlaprevir and Artesunate for SARS-CoV-2 and malaria respectively. Theoretically, most compounds didn’t show toxicity except compounds 2a, 2i, and 2k, exhibiting hepatotoxic activity. Molecular dynamics was used to prove and assess their binding stability to the target protein for each activity. The 3SRJ-2f and 6HZD-2l structures were selected for anti-malarial and anti-SARS-CoV-2 activity respectively. The 3SRJ-2f and 6HZD-2l complexes showed stable interactions to 100 ns between the inhibitor fragments and the residual amino acids of the protein. To conclude, these novel compounds are probably to become promising lead molecules for the development of effective anti-SARS-CoV-2 and/or anti-malarial of all drugs. Keywords: Catechin, Anti-malarial, Anti-SARS-CoV-2, Docking and Dynamic Molecular, ADMET Analysis.