Repurposing of FDA Approved Alkaloids as COVID 19 Inhibitors; in silico Studies

Background: Alkaloid drugs were permitted for using as a treatment of numerous diseases. Colchicine, codeine, piperine, papaverine, ergometrine, theophylline, theobromine and caffeine are recognized safe alkaloids and used for many human disfunctions. The chemical structures of alkaloids have flexible chemical moieties with various electronic and chemical characters. COVID-19 is a horrible disease as result from that the discovering of potent drugs from previously FDA approved drugs is the main objective of this study. Methods: docking studies were used for discovering the interactions of alkaloids with protease proteins. The nature of selected alkaloids structures was utilized for advance insights studies to predict new medical applications. Results: Docking studies for alkaloids were completed and the obtained outcomes, displayed that all tried alkaloids have great attraction with the five protease proteins, the energy docking score ranged from -2.9516 (for colchicine with 5R82) to -24.7449 (for ergotamine with 5R80) kcal/mol with 1-5 variable interactions bond. Conclusion: Among the tested drugs, papaverine and ergometrine revealed high docking scores for all five proteins (score ranged from, -14.1058 to 23.1619 for papaverine and, -4.7900 to 24.7449 for ergometrine) and number of interactions with all tested proteins are two to three for papaverine but for ergometrine are two to five.