In Silico Study of Coumarins: Wedelolactone as a Potential Inhibitor of the Spike Protein of the SARS-CoV-2 Variants

Table 1

Binding interaction analysis of the top 10 best-docked coumarins and reference ligands with SARS-CoV-2 Omicron S-RBD.

S.N.	Compounds	Binding energy (kcal/mol)	Interacting residues	Interaction types	Interacting distance (Å)
1	Inophyllum C	−7.6	SER 494	Conventional H bond	1.95
			PHE 490	Pi-Pi stacked	4.87
			ARG 493	Pi-alkyl	4.38
2	(+)-Rutamarin	−7.5	TRP 436	Pi-Pi T-shaped	5.46, 5.74
			LYS 440	Alkyl	4.69
			PRO 373	Pi-alkyl	5.27, 5.33
3	Cordatolide A	−7.5	SER 494	Conventional H bond	2.07
			ARG 493	Pi-alkyl	3.77, 4.12
4	Soulattrolide	−7.5	SER 494	Conventional H bond	2.26
			PHE 490	Pi-Pi stacked	3.90, 5.27
			ARG 493	Pi-alkyl	5.21, 5.34
5	Wedelolactone	−7.4	TYR 449	Conventional H bond	2.31
			SER 494	Conventional H bond	2.35
			ARG 493	Pi-sigma, Pi-alkyl	3.73, (5.35)
			LEU 452	Pi-sigma	3.80, 5.14
			PHE 490	Pi-Pi stacked	5.33
6	Inophyllum A	−7.4	ASP 339	Pi-anion	4.03, 4.25
			LEU 371	Pi-alkyl	5.36
			LEU 368	Pi-alkyl	5.47
7	Inophyllum E	−7.4	SER 494	Conventional H bond	1.89
			PHE 490	Pi-Pi stacked	4.41, 5.84
			ARG 493	Pi-alkyl	4.75
8	(+)-Calanolide C	−7.3	SER 494	Conventional H bond	2.03, 2.51
			PHE 490	Pi-sigma	3.96
			ARG 493	Pi-alkyl	3.78, 4.13
9	Inophyllum B	−7.3	SER 494	Conventional H bond	2.43
			PHE 490	Pi-Pi stacked	3.85, 5.18
			ARG 493	Pi-alkyl	5.25, 5.28
10	Inophyllum D	−7.3	SER 494	Conventional H bond	1.88
			PHE 490	Pi-Pi stacked	4.27, 5.79
			ARG 493	Pi-alkyl	4.72
Reference ligands	Ceftazidime	−6.5	TYR 453	Conventional H bond	1.90
			ARG 403	Conventional H bond	2.45, 6.00
			SER 496	Conventional H bond	2.00
			HIS 505	Pi-cation, (C-H bond)	3.46, (4.08)
	Molnupiravir	−6.1	TYR 453	Conventional H bond	2.05
			ARG 403	Conventional H bond	2.20
			SER 496	C-H bond	3.33, 3.45
			ARG 493	C-H bond	3.46
			HIS 505	Pi-sigma	3.87