Transfer hydrogenation in open-shell nucleotides - a theoretical survey.
Florian Achrainer1, Hendrik Zipse2
1Department of Chemistry, Ludwig-Maximilians-Universität Munich, Butenandtstr. 5-13, Munich 81377, Germany.
Molecules (Basel, Switzerland)
|December 24, 2014
Summary
Many sugar models can act as potent dihydrogen donors in transfer hydrogenation reactions, reducing pyrimidine bases like uracil. The C3' ribosyl radical is the most effective reducing agent identified in this study.
Area of Science:
- Biophysical Chemistry
- Organic Chemistry
- Computational Chemistry
Background:
- Transfer hydrogenation is a key reaction in organic synthesis and biological processes.
- Sugars and nucleobases play crucial roles in biological systems.
- Understanding the reducing potential of biomolecules is important for mechanistic studies.
Purpose of the Study:
- To quantify the potential of sugar models as dihydrogen donors in transfer hydrogenation.
- To compare the reducing power of sugar fragments with nucleobases.
- To investigate intramolecular transfer hydrogenation in uridinyl radicals.
Main Methods:
- Calculation of hydrogenation energies for oxidized sugar and nucleobase products.
- Energetic analysis of radical species.
- Computational modeling of reaction pathways.
Main Results:
- Numerous sugar fragment radicals can reduce pyrimidine bases, such as uracil, exothermically.
- The C3' ribosyl radical exhibits the strongest reducing potential among the studied sugar fragments.
- Intramolecular transfer hydrogenation in uridinyl radicals is energetically favorable, particularly for the uridin-C3'-yl radical.
Conclusions:
- Sugar fragments possess significant reducing capabilities relevant to biochemical reactions.
- The C3' ribosyl radical is a highly effective dihydrogen donor.
- Intramolecular reactions within uridinyl radicals can proceed with a substantial thermodynamic driving force.
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