Synthesis of dimeric phenol derivatives and determination of in vitro antioxidant and radical scavenging activities

Figures & data

Figure 1 The structures of DMP, DIP and DTP and their synthesed dimeric compounds Di-DMP, Di-DIP and Di-DTP.

Figure 2 The synthesit scheme for preparation of dimeric phenols from their monomeric forms.

Figure 3 Total antioxidant activities of Di-DMP, Di-DIP, Di-DTP, BHA, BHT, α-tocopherol and trolox at the same concentration (45 μg/mL) in the linoleic acid emulsion system by the ferric thiocyanate method.

Figure 4 Total reductive potential of different concentrations (15–30 μg/mL) of Di-DMP, Di-DIP, Di-DTP, BHA, BHT, α-tocopherol and trolox using the Fe³⁺-Fe²⁺ transformation.

Table I.  Comparison of hydrogen peroxide (H₂O₂) scavenging activity, ferrous ion (Fe²⁺) chelating activity and superoxide anion radicals (O₂^√–) scavenging activity of Di-DMP, Di-DIP, Di-DTP and the standard antioxidants BHA, BHT, α-tocopherol and trolox at concentration of 15 μg/mL.

	H2O2 scavenging activity (%)	Ferrous ion chelating activity (%)	Superoxide scavenging activity (%)
BHA	36.4 ± 3.5	69.9 ± 7.5	75.3 ± 6.5
BHT	34.3 ± 4.1	60.0 ± 9.3	70.2 ± 7.1
α-Tocopherol	39.3 ± 2.9	31.3 ± 5.5	22.2 ± 3.3
Trolox	25.5 ± 3.3	45.2 ± 6.2	16.0 ± 1.9
Di-DMP	38.2 ± 7.8	63.6 ± 4.7	67.4 ± 5.2
Di-DIP	30.3 ± 4.8	61.3 ± 4.2	33.7 ± 5.2
Di-DTP	20.4 ± 3.9	58.2 ± 2.3	33.1 ± 6.3

Figure 5 DPPH· free radical scavenging activity of Di-DMP, Di-DIP and Di-DTP, α-tocopherol and trolox.

Figure 6 ABTS^√+ radical scavenging activity of Di-DMP, Di-DIP and Di-DTP, α-tocopherol and trolox.