Table 1.

In vitro activities of perampanel analogs

Compound	IC50 (μM)
Perampanel	100–250
2	9.99 ± 2.50
3	6.38 ± 1.21
4	4.02 ± 1.36
5	0.14 ± 0.02
6	0.47 ± 0.02
11	0.120 ± 0.016
14	0.128 ± 0.015
15	0.110 ± 0.013
16	0.100 ± 0.035
19	0.037 ± 0.007
21	0.018 ± 0.002
23	0.020 ± 0.005
25	0.025 ± 0.003
26	0.170 ± 0.022
29	0.25–0.50
31	0.037 ± 0.004
50	0.25–0.50

Activities of perampanel and analogs 2–50 with previously reported IC₅₀s of perampanel and compounds 2–26 (Zhang et al., 2021) with standard deviation calculated from triplicate measurements. While IC₅₀ values could not be calculated for compounds 29 and 50 due to incomplete inhibition at maximum concentrations tested, in vitro activity data demonstrate that both compounds reduce M^pro activity to 50% between 0.25 μM and 0. 5 μM (Figure S2).