. 2021 Dec 27;23(1):259. doi: 10.3390/ijms23010259

Table 3.

Data from the 15 most potent non-covalent inhibitors of the SARS-CoV-2 M-pro.

Compound	IC₅₀ μM (pIC₅₀)	EC₅₀ μM	CC₅₀ μM	Reference
339096-59-2 (M3)	0.013 (7.89)	0.016 ^a	Higher than the EC₅₀ by 2.3-fold	[101]
2603242-35-7 (21)	0.018 (7.74)	11.30 ^a,b	1.7 ^a	[44]
2603242-41-5 (23; 18)	0.024 (7.62)	0.84 ^a,b	1.15 ^a	[44,46]
2679814-93-6 (19)	0.044 (7.36)	0.08 ^a	>32.5 ^a	[46]
2679814-92-5 (17)	0.059 (7.23)	0.82 ^a	>100 ^a	[46]
2679814-91-4 (16)	0.061 (7.22)	1.20 ^a	82 ^a	[46]
2679814-96-9 (21)	0.061 (7.22)	1.08 ^a	>100 ^a	[46]
2694063-46-0 (21)	0.063 (7.20)	1.74 ^a	-	[49]
CCF0058981 (41)	0.068 (7.17)	0.50 ^a	>50 ^a	[49]
81418-42-0 (15)	0.072 (7.14)	4.55 ^a	viability ^a >90% at conc. <= 20 μM	[103]
2694063-44-8 (19)	0.106 (6.98)	5.76 ^a	-	[49]
392732-12-6 (13)	0.11 (6.96)	0.11 ^a	0.41 ^c	[102]
PET-UNK-29afea89-2	0.129 (6.92)	0.244 ^d	lack of toxicity ^d	[40]
2603242-04-0 (14)	0.128 (6.89)	3.20 ^a	12.3 ^a	[44]
2694063-65-3 (40)	0.171 (6.77)	1.91 ^a	-	[49]

^a In Vero E6 cells. ^b Lacked antiviral activity in an MTT assay. ^c In mammalian cells. ^d In Calu-3 cell line.