Percent of antioxidant activity of the new coumarin compoundsa.
| Compounds | Concentration (0.01 mg) | Concentration (0.05 mg) |
|---|---|---|
| 4a | 31.8 ± 0.2 | 40.9 ± 3.1 |
| 4b | 31.8 ± 1.2 | 35.00 ± 1.00 |
| 4c | 28.00 ± 0.4 | 57.14 ± 2.77 |
| 4d | 4.5 ± 0.4 | 10.3 ± 0.33 |
| Vitamin C | 80.00 ± 5.00 | 89.00 ± 6.99 |
Data are means ± SD of three replicates in each group.