Structural Chemistry
Energy requirements of the reactions of kaempferol and selected radical species in different media: towards the prediction of the possible radical scavenging mechanisms
Jasmina M. Dimitrić Marković*a, Dejan Milenkovićb, Dragan Amićc,
Ana Popović-Bijelića, Miloš Mojovića, Igor A. Pašti a, Zoran S. Markovićb,d
Fig.S1 Absorbance of malonaldehyde–TBA complex at 532nm: at various Fe(II) concentrations in the presence or absence of EDTA and kaempferol (concentrations are indicated in the spectra).
Fig. S2 Absorbance of malonaldehyde–TBA complex at 532 nm at various
Fe(II) concentrations in the absence and presence of equimolar EDTA
Fig. S3 Recovery of kaempferol from iron(III)-kaempferol complex (pH 8) induced by different concentrations of EDTA: (1) pure kaempferol; (2) iron(III)-kaempferol complex; (3) 0.3 mM EDTA; (4) 1.5 mM EDTA; (5) 3.1 mM EDTA (6) 4.8 mM EDTA (7) 6.5 mM EDTA (8) 11.5mM EDTA; (9) 13.0 mM EDTA; (10) 15.0 mM EDTA
Fig. S4 Cyclic voltammograms of kaempferol (0.5 mM) in 0.1 M K2SO4, recorded at 50 mV s-1 at pH 3, 7 and 9; scan rate 50 mV s-1.
Table S1 Calculated reaction free energy (kJ/mol) for the reactions of kaempferol with hydroxyl radical and superoxide radical anion
M05-2X/6-311G(d,p)Water (ε=78.35) / DMSO (ε=46.83)
Kaempferol / HAT / SET-PT / SPLET / HAT / SET-PT / SPLET
ΔGBDE / ΔGIP / ΔGPDE / ΔGPA / ΔGETE / ΔGBDE / ΔGIP / ΔGPDE / ΔGPA / ΔGETE
99 / 241
KOH-3 + .OH / -153 / -252 / -131 / -22 / -145 / -385 / -220 / 75
KOH-4’ + .OH / -129 / -228 / -130 / 1 / -129 / -370 / -236 / 107
KOH-5 + .OH / -99 / -198 / -125 / 26 / -82 / -322 / -215 / 133
KOH-7 + .OH / -99 / -198 / -145 / 46 / -96 / -337 / -250 / 154
372 / 690
KOH-3 + .OO- / 57 / -315 / 13 / 45 / 94 / -596 / -28 / 122
KOH-4’ + .OO- / 82 / -291 / 14 / 68 / 95 / -581 / -44 / 153
KOH-5 + .OO- / 112 / -261 / 19 / 93 / 143 / -533 / -23 / 180
KOH-7 + .OO- / 112 / -261 / -1 / 113 / 128 / -547 / -58 / 201
Ethanol (ε=24.85) / DMF (ε=37.22)
134 / 243
KOH-3 + .OH / -155 / -289 / -153 / -1 / -144 / -387 / -221 / 76
KOH-4’ + .OH / -127 / -261 / -160 / 33 / -126 / -369 / -237 / 110
KOH-5 + .OH / -100 / -234 / -149 / 49 / -82 / -325 / -214 / 133
KOH-7 + .OH / -102 / -236 / -170 / 68 / -96 / -339 / -252 / 155
452 / 695
KOH-3 + .OO- / 65 / -387 / 5 / 61 / 94 / -601 / -29 / 123
KOH-4’ + .OO- / 93 / -359 / -2 / 95 / 112 / -583 / -45 / 157
KOH-5 + .OO- / 120 / -332 / 9 / 112 / 156 / -539 / -23 / 179
KOH-7 + .OO- / 118 / -334 / -12 / 131 / 142 / -553 / -60 / 202
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