Table 1.

Molecular docking scores and binding features for compound 3a–g and Darunavir with SARS-CoV-2 main protease (M^pro)

No.	Compound	Docking score (kcal/mol)	Binding features (hydrogen bond length in Å
1	3a	− 8.28	ARG188 (2.18 Å), MET165 (2.63 Å), HIS164 (2.14 Å), GLU166 (2.17 Å, 2.79 Å)
2	3b	− 8.14	ARG188 (2.81 Å), GLN192 (2.37 Å), THR190 (2.09 Å), GLU166 (2.03 Å)
3	3c	− 7.05	ARG188 (1.82 Å), THR190 (2.60 Å) GLN192 (1.93 Å), GLU166 (1.82 Å, 1.96 Å)
4	3d	− 8.30	GLU166 (2.05 Å), ARG 188 (1.80 Å), THR190 (2.08 Å), GLN192 (2.38 Å)
5	3e	− 8.63	THR190 (2.1 Å), GLN192 (2.38 Å), ARG188 (1.79 Å), GLU166 (2.08 Å)
6	3f	− 7.72	GLN189 (1.94 Å), GLU166 (2.01 Å, 2.33 Å)
7	3g	− 7.38	GLU166 (2.82 Å)
8	Darunavir	− 8.19	GLU166 (1.94 Å, 2.88 Å), LEU167 (1.96 Å)