Table 2.

In silico studies of alkaloids with potential anti-SARS-CoV-2 activity.

Alkaloid	Chemical structure	Mechanisms of action	Type of study	References
(-)-asperlicin C		3CLpro inhibitory, blocking ACE2	Molecular docking	[70]
3α,17α-Cinchophylline		Cathepsin L inhibitor	Molecular docking	[72]
10-Hydroxyusambarensine		3CLpro inhibitor	Molecular docking	[49]
18-Hydroxy-3-epi-alphayohimbine		3CLpro inhibitor	Molecular docking	[61]
6-Acetonyldihydrochelerythrine		RdRp inhibitor	Molecular docking	[38]
Adlumidine		TMPRSS2 inhibitors	Molecular docking	[72]
Ajmalicine		Blocking Nsp15	Molecular docking	[74]
Allocryptopine		RdRp inhibitor	Molecular docking	[38]
Alloyohimbine		3CLpro inhibitor	Molecular docking	[61]
Amaranthin		3CLpro inhibitor	Molecular docking	[85]
Anisotine		Mpro inhibitor	Molecular docking	[59]
Asparagamine A		3CLpro inhibitor	Molecular docking	[61]
Berberine		3CLpro inhibitory, blocking ACE2 and Nsp15	Molecular docking	[10, 39, 74]
Cadambine		3CLpro inhibitory	Molecular docking	[86]
Caffeine		Blocking ACE2	Molecular docking	[83]
Chrysopentamine		3CLpro inhibitor	Molecular docking	[49]
Crambescidin 786		Blocking Nsp 10	Molecular docking	[82]
Crambescidin 826		Blocking the N proteins	Molecular docking	[82]
Cryptomisrine		Mpro and RdRp inhibitor	Molecular docking	[50]
Cryptoquindoline		Mpro and RdRp inhibitor	Molecular docking	[49, 50]
Cryptospirolepine		Mpro and RdRp inhibitor	Molecular docking	[49, 50]
Dihydroergotamine		3CLpro inhibitor	Molecular docking	[63]
Epiisopiloturine		Mpro inhibitor	Molecular docking	[90]
Ergometrine		Mpro inhibitor	Molecular docking	[65]
Ergotamine		3CLpro inhibitor	Molecular docking	[63]
Fumigatoside E		Blocking ACE2	Molecular docking	[79]
Indican		Mpro inhibitor	Molecular docking	[40]
Indigo		Mpro inhibitor	Molecular docking	[40]
Indirubin		Mpro inhibitor	Molecular docking	[40]
Nicotine		Blocking ACE2	Molecular docking	[83]
Norquinadoline A		Blocking ACE2 and PLpro inhibitor	Molecular docking	[80, 81]
Noscapine		Mpro inhibitor	Molecular docking	[77]
Noscapine 23B		Mpro inhibitor	Molecular docking	[78]
Oriciacridone F		3CLpro inhibitory, blocking ACE2	Molecular docking	[70]
Oxoturkiyenine		Cathepsin L inhibitor	Molecular docking	[72]
Palmatine		3CLpro inhibitor	Molecular docking	[66]
Papaverine		Mpro inhibitor	Molecular docking	[65]
Piperine		ACE2 blocker	Molecular docking	[39]
Protopine		RdRp inhibitor	Molecular docking	[38]
Pseudojervine		ACE2 blocker	Molecular docking	[84]
Qingdainone		Inhibitors of TMPRSS2	Molecular docking	[72]
Reserpine		Blocking the Nsp15	Molecular docking	[74]
Sanguinarine		3CLpro inhibitor	Molecular docking	[66]
Solanidine		Blocking the S proteins, Mpro inhibitor	Molecular docking	[58]
Sophaline D		Mpro inhibitor	Molecular docking	[45]
Sophoridine		Mpro inhibitor	Molecular docking	[62]
Speciophylline		3CLpro inhibitor	Molecular docking	[86]
Tabersonine		3CLpro inhibitor	Molecular docking	[66]
Taspine		Blocking Nsp15	Molecular docking	[74]
Tetrahydropalmatine		3CLpro inhibitor	Molecular docking	[10]
Thalimonine		Mpro inhibitor	Molecular docking	[45]
Thebaine		ACE2 blocker	Molecular docking	[39]
Tryptanthrine		Mpro inhibitor	Molecular docking	[40]
Vincapusine		3CLpro inhibitor	Molecular docking	[61]

3CL^pro: 3-chymotrypsin-like protease, ACE2: angiotensin-converting enzyme 2, E proteins: envelope proteins, Mpro: main proteases, NI: not identified, N proteins: nucleocapsid proteins, Nsp15: nonstructural proteins, RdRp: RNA-dependent RNA polymerase, S proteins: spike proteins, TMPRSS2: transmembrane protease serine 2.