In this study, we studied fifteen marine polycyclic batzelladine alkaloids against SARS-CoV-2 M pro in silico, aiming to evaluate their binding energies and binding mode to the active site of M pro . Before discussing the compounds' binding energies, we represent the analysis curves for the MD simulations of the M pro of the SARS-CoV-2 system (a dimer) using VMD software and some in-house analysis codes. Figure shows the Root Mean Square Deviation (RMSD) in Å (blue line), the Radius of Gyration (RoG) in Å (orange line), and the Surface Accessible Surface Area (SASA) in Å 2 (gray line). As reflected from the curves, the system was equilibrated during the first 10 ns of the simulation with an RMSD value of 1.8 Å. Additionally, the RoG and SASA values (26.0 Å and 27100 Å 2 , respectively) and patterns indicate system equilibration during the simulation period.