Table 2.

Results of Vero E6 cytotoxicity and SARS-CoV-2 antiviral activity of novel pyranopyrazoles.

ID	Vero E6 Cytotoxicity (IC50, µM)	SARS-CoV-2 Antiviral Assay (%)		Antiviral Potency Index (API)*
		1 µM	10 µM
18	60.5 ± 4.6	12.91 ± 0.06	69.21 ± 0.51	0.74
19	26.2 ± 20	10.21 ± 0.046	42.16 ± 0.23	0.45
20	103 ± 7.8	7.424 ± 0.034	58.13 ± 0.37	0.62
21	78.1 ± 5.9	1.515 ± 0.007	45.82 ± 0.27	0.49
22	67.7 ± 5.2	36.85 ± 0.19	90.45 ± 1.01	0.97
23	113 ± 8.6	18.65 ± 0.089	59.3 ± 0.31	0.64
24	60.7 ± 4.6	10.89 ± 0.05	50.31 ± 0.30	0.54
25	47.6 ± 3.6	0.758 ± 0.003	48.49 ± 0.29	0.52
26	34.8 ± 2.7	7.424 ± 0.09	42.99 ± 0.48	0.46
27	62 ± 4.70	20.46 ± 0.03	91.23 ± 0.25	0.98
28	131 ± 10	22.82 ± 0.11	47.75 ± 0.28	0.51
29	63.3 ± 4.8	5.303 ± 0.02	46.21 ± 0.26	0.50
30	66.5 ± 5.1	3.03 ± 0.01	27.84 ± 0.14	0.30
31	18.1 ± 1.4	21.06 ± 0.10	75.78 ± 0.61	0.81
32	45.7 ± 3.5	23.4 ± 0.11	63.37 ± 0.43	0.68
33	86.2 ± 6.6	28.38 ± 0.14	77.66 ± 0.65	0.83
Remdesivir	61.8 ± 4.7	89.61 ± 0.98	93.33 ± 1.17	1.00

^*API is the ratio between the % inhibition of tested compound to that of the remdesivir reference drug at 10 µM. SE represents standard deviation calculated from triplicate readings.