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Fragmentation of β-hydroxy hydroperoxides
Xiaodong Gu1, Wujuan Zhang, Robert G Salomon
1Department of Chemistry, Case Western Reserve University, Cleveland, Ohio 44106, USA.
The Journal of Organic Chemistry
|December 30, 2011
Summary
Vitamins E and C break down a specific hydroperoxide, creating aldehydes. This process, especially with iron, may cause oxidative injury by damaging proteins and DNA.
Area of Science:
- Biochemistry
- Organic Chemistry
- Oxidative Stress Research
Background:
- Singlet oxygenation of cyclohepta-1,4-diene yields a hydroperoxy endoperoxide.
- Base-catalyzed disproportionation of this endoperoxide produces a β-hydroxy hydroperoxide.
Purpose of the Study:
- To investigate the fragmentation of β-hydroxy hydroperoxide induced by vitamins E and C.
- To explore the role of redox-active metal ions, like iron, in this fragmentation process.
- To understand the potential contribution of this chemistry to oxidative injury.
Main Methods:
- Singlet oxygenation of cyclohepta-1,4-diene.
- Base-catalyzed disproportionation.
- Fragmentation assays involving vitamins E and C, and metal ions.
Main Results:
- β-hydroxy hydroperoxide was synthesized.
- Vitamins E and C induced fragmentation of β-hydroxy hydroperoxide, generating aldehydes.
- Redox-active metal ions, particularly iron, enhanced aldehyde generation.
- This aldehyde formation pathway may mimic oxidative cleavage of polyunsaturated fatty acyls.
Conclusions:
- The fragmentation of β-hydroxy hydroperoxide by vitamins E and C, especially with iron, generates aldehydes.
- This chemical pathway could contribute to the formation of reactive aldehydes implicated in oxidative injury.
- The findings provide insights into mechanisms of oxidative damage to proteins and DNA.
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