Table 2.
AChE and BChE inhibitory activities of flavonols 2a–p.
| Compound | IC50 (µM) | SI | ||
|---|---|---|---|---|
| AChE | BChE | BChE/AChE | AChE/BChE | |
| 2a | 38.78 ± 0.01 | 28.06 ± 0.10 | 0.72 | 1.38 |
| 2b | 16.60 ± 0.03 | 19.73 ± 0.05 | 1.19 | 0.84 |
| 2c | 10.50 ± 0.08 | 14.58 ± 0.14 | 1.39 | 0.72 |
| 2d | 10.95 ± 0.30 | 8.49 ± 0.05 | 0.78 | 1.29 |
| 2e | 10.64 ± 0.07 | 25.19 ± 0.30 | 2.37 | 0.46 |
| 2f | 9.57 ± 0.20 | 17.86 ± 0.08 | 1.87 | 0.54 |
| 2g | 11.00 ± 0.06 | >100 | - | - |
| 2h | 11.72 ± 0.07 | 4.17 ± 0.15 | 0.36 | 2.81 |
| 2i | 58.14 ± 0.21 | 14.11 ± 0.11 | 0.24 | 4.12 |
| 2j | 10.98 ± 0.03 | 5.73 ± 0.05 | 0.52 | 1.92 |
| 2k | 11.56 ± 0.05 | 10.44 ± 0.09 | 0.90 | 1.11 |
| 2l | 10.51 ± 0.03 | 15.25 ± 0.01 | 1.45 | 0.69 |
| 2m | 10.01 ± 0.09 | 9.52 ± 0.03 | 0.95 | 1.05 |
| 2n | 9.38 ± 0.07 | 5.91 ± 0.05 | 0.63 | 1.59 |
| 2o | 11.07 ± 0.12 | 11.63 ± 0.17 | 1.05 | 0.95 |
| 2p | 10.96 ± 0.03 | 4.89 ± 0.02 | 0.45 | 2.24 |
| Donepezil | 4.77 ± 0.06 | 6.04 ± 0.03 | 1.27 | 0.79 |
The values are given as mean ± standard deviation (SD) in three independent experiments. SI (Selectivity Index): the AChE selectivity index is defined as IC50 (BChE)/IC50 (AChE) and that of BChE as IC50 (AChE)/IC50 (BChE) affinity ratios.