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Antioxidative effect of some hydroxy substituted aromatic bisimines
Frantisek Sersen1, Martin Walko, Dusan Loos
1Institute of Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská dolina CH2, 842 15 Bratislava, Slovakia. sersen@fns.uniba.sk
General Physiology and Biophysics
|July 14, 2009
Summary
Researchers synthesized novel antioxidant compounds structurally similar to resveratrol. Derivatives with hydroxyl groups at the 2 and 5 positions effectively scavenged DPPH radicals, unlike those with groups at the 2 and 4 positions.
Area of Science:
- Medicinal Chemistry
- Organic Chemistry
- Computational Chemistry
Background:
- Resveratrol is a well-known antioxidant with potential health benefits.
- Exploring novel compounds with similar structures can lead to improved therapeutic agents.
- Understanding structure-activity relationships is crucial for designing effective antioxidants.
Purpose of the Study:
- To synthesize and evaluate the antioxidative properties of novel diphenylmethane and diphenylether derivatives.
- To investigate the influence of hydroxyl group positions on radical scavenging activity.
- To computationally support experimental findings regarding antioxidant efficacy.
Main Methods:
- Synthesis of four derivatives of 4,4'-bis(dihydroxybenzylanilidenamino) diphenylmethanes and diphenylethers.
- Antioxidant activity assessment using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay in methanol and chloroform.
- Quantum chemical calculations (AM1 method) to determine free enthalpies of anion/radical formation.
Main Results:
- Derivatives with hydroxyl groups at the 2 and 5 positions exhibited significant DPPH radical scavenging activity.
- Derivatives with hydroxyl groups at the 2 and 4 positions showed negligible DPPH radical scavenging.
- Computational analysis supported the experimental data, showing lower formation enthalpies for effective scavengers.
- None of the synthesized compounds effectively scavenged hydroxyl radicals, unlike resveratrol.
Conclusions:
- The position of hydroxyl groups critically influences the antioxidant capacity of these resveratrol analogs.
- The 2,5-dihydroxy substitution pattern is optimal for DPPH radical scavenging in this compound class.
- These findings provide valuable insights for the design of new antioxidant molecules.
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