Table 3. Nucleophilicity, Softness and pKa Values of Thiolate and Enolate Anions .
HSAB and ionization parameters for thiolate and enolate nucleophilicities. Softness (σ) and nucleophilicity (ω− with NAPQI as the reacting electrophile) for the selected chemicals were calculated as described in Materials and Methods. Abbreviations: NAC – N-acetylcysteine; GSH – glutathione; 2-ACP – 2-acetylcyclopentanone; THA - 2’,4’,6’-trihydroxyacetophenone; PG - 1,3,5-trihydroxyacetophenone.
| Anion | σ (×10−3 ev−1) | ω− (×10−3 ev) | pKa |
|---|---|---|---|
| NAC | 367 | 667 | 9.5 |
| GSH | 427 | 548 | 8.6 |
| 2-ACP | 418 | 485 | 7.8 |
| THA | 485 | 325 | 7.7 |
| PG | 366 | 540 | 8.5 |
| Curcumin | 604 | 307 | 7.8 |
| Phloretin | 494 | 221 | 7.3 |