Transition metal complexes as potential tools against SARS-CoV-2: an in silico approach

Abstract

The current global pandemic crisis caused by the outbreak of the SARS-CoV-2 virus has caused more than 1.3 million deaths worldwide and forced social distancing among the people affecting the socio-economic condition. The virus is spread by human contact and respiratory droplets targeting the ACE2 receptors of alveolar cells. The virus replication process involves the translation of the viral genome, which involves the formation of an RNA-dependent RNA polymerase complex and the inhibition of the replication process of the virus can be triggered by the inhibition of the RNA-dependent RNA polymerase complex. The WHO has approved the repurposing of current antiviral drugs as the treatment protocol for COVID-19. Nevertheless, the use of present antiviral drugs and strict social distancing are unable to stop the outbreak of COVID-19. Transition metal complexes, by virtue of a broad spectrum of oxidation numbers, valencies, geometries, tunable redox, and kinetic and thermodynamic properties provide us with a platform in considering such compounds as the viable alternative of the present re-purposed antiviral drugs against SARS-CoV-2. Herein, we have selected eleven metal-based antiviral agents and performed molecular docking in the RdRp complex of SARS-CoV-2. The docking results revealed that metal complexes potentially inhibit the RdRp of SARS-Cov-2 the binding energy (−10.24 kcal mol⁻¹) of which is comparably higher with respect to the reported binding energies of the conventional re-purposed drugs like Chloroquine, Remdesivir, Ribavirin, etc. (−4 to −7 kcal mol⁻¹). The most competent candidate shows the highest binding energy of −10.24 kcal mol⁻¹ corresponding to ferroquine derivative complex 6. The results are of paramount importance and enable us to consider these transition metal complexes as the potential treatment modality against SARS-CoV-2 and warrant further in vitro or in vivo screening of these complexes in the clinical arena of COVID-19 research.