Table 2.
IC50 and TEACFRAP values for phenolic acids with the calculated thermodynamic parameters: bond dissociation enthalpy (BDE), ionization potential (IP), proton dissociation enthalpy (PDE), proton affinity (PA), electron transfer enthalpy (ETE). Based on [75].
| 4-Hydroxybenzoic Acid | Isovanillic Acid | Vanillic Acid | Protocatechuic Acid | Syringic Acid | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| ICDPPH (mM) | >1000 | 3.777 ± 0.160 | 3.38 ± 0.053 | 0.052 ± 0.002 | 0.043 ± 0.002 | |||||||
| TEACFRAP (mol TE/mol) |
0.002 ± 0.001 | 0.155 ± 0.010 | 0.165 ± 0.019 | 1.46 ± 0.056 | 1.128 ± 0.037 | |||||||
| OH position | 4 OH | 3 OH | 4 OH | 3 OH | 4 OH | 4 OH | ||||||
| Solvent | C2H6O | H2O | C2H6O | H2O | C2H6O | H2O | C2H6O | H2O | C2H6O | H2O | C2H6O | H2O |
| BDE (kcal/mol) | 88.9 | 85.5 | 83.38 | 80.8 | 83.77 | 79.8 | 83.3 | 80.9 | 81.37 | 79.2 | 78.9 | 77.3 |
| IP (kcal/mol) | 129.2 | 120.6 | 118.8 | 110.9 | 118.9 | 110.8 | 120.5 | 112.6 | - | - | 115.8 | 108.3 |
| PDE (kcal/mol) | 6.2 | 13.3 | 11.0 | 17.0 | 1.31 | 9.8 | 9.31 | 5.5 | 7.3 | 13.7 | 9.71 | 6.1 |
| PA (kcal/mol) | 38.9 | 41.5 | 39.6 | 41.3 | 43.7 | 45.3 | 42.9 | 44.6 | 35.2 | 38.1 | 39.4 | 41.7 |
| ETE (kcal/mol) |
96.6 | 92.4 | 86.1 | 82.7 | 90.6 | 89.4 | 87.0 | 83.5 | 92.6 | 88.3 | 92.6 | 88.3 |