Table 2. Antiviral Entry Activities of Quinoxalines for SARS-CoV-2 Spike Pseudovirus into HEK-293T-ACE2h Host Cells.
| compounds | CC0a (μM) | TC50b (μM) | IC50c (μM) | SId |
|---|---|---|---|---|
| 4aa | >250 | >25 | NDe | NDe |
| 4ba | 125 | 271.67 ± 13.00 | ND | ND |
| 4ca | 125 | 276.90 ± 13.45 | 19.70 ± 1.23 | 14.05 |
| 4ha | >250 | >500 | 142.50 ± 12.45 | >3.50 |
| 4ia | 25 | 115.20 ± 9.72 | ND | ND |
| 4ja | 25 | >100 | ND | ND |
| 4ka | 25 | >100 | ND | ND |
| 4pa | >25 | >250 | ND | ND |
| 4ra | 62.5 | 337.06 ± 15.49 | ND | ND |
| 4ab | 62.5 | 288.40 ± 17.65 | ND | ND |
| 4ac | 50 | 116.03 ± 4.28 | ND | ND |
| 4ad | >25 | >500 | 21.28 ± 0.44 | >23.49 |
| 4ae | 125 | 303.27 ± 9.51 | ND | ND |
| 4af | 100 | >100 | ND | ND |
| 4ag | 50 | 107.20 ± 1.64 | ND | ND |
| 6pf | >100 | >100 | 11.90 ± 0.59 | >8.40 |
| antibodyg | 0.10 | ND | 0.032 ± 0.001 | ND |
a
CC0 represents the maximum nontoxic concentration of compounds.
b
TC50 means the concentration that caused 50% cells’ death.
c
IC50 stands for the compounds’ concentration that suppressed 50% viral entry into HEK-293T-ACE2h host cells.
d
SI represents selectivity index that indicates compounds’ window between cytotoxicity and antiviral activity by the ratio of TC50/IC50.
e
ND means not determined.
f
honokiol derivative 6p (a reported ACE2 blocker).
g
SARS-CoV-2 antibody was utilized as a positive control compound for antiviral entry evaluation.