| Compound No. | DPPH % inhibition anti-oxidant ± SD | |
| 150 mmol·L−1 | 300 mmol·L−1 | |
| 6 | 52.09 ± 0.06 | 55.5 ± 0.18 |
| 7 | 5.80 ± 0.21 | 51.99 ± 0.80 |
| 8 | 55.11 ± 0.05 | 60.55 ± 0.15 |
| 9 | 50.76 ± 0.25 | 50.78 ± 0.01 |
| 10 | 52.85 ± 0.21 | 59.01 ± 0.04 |
| 12 | 45.08 ± 0.05 | 46.66 ± 0.05 |
| 13 | 48.85 ± 0.11 | 49.00 ± 0.01 |
| 16 | 44.33 ± 0.14 | 45.55 ± 0.01 |
| 17 | 43.89 ± 0.13 | 45.99 ± 0.015 |
| Ascorbic acid | 43.00 | 50.70 |