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Probing structural properties and antioxidant activity mechanisms for eleocarpanthraquinone
José L F Santos1, Angélica C Kauffmann1, Sebastião C da Silva1
1Departamento de Química, Universidade Federal de Mato Grosso, Cuiabá, Mato Grosso, 78060-900, Brazil.
Journal of Molecular Modeling
|August 18, 2020
Summary
Computational studies reveal eleocarpanthraquinone
Area of Science:
- Computational Chemistry
- Organic Chemistry
- Materials Science
Background:
- Eleocarpanthraquinone is a newly isolated polyphenolic anthrone-anthraquinone.
- Understanding its structural and energetic properties is crucial for potential applications.
Purpose of the Study:
- To computationally investigate the structure and energetics of eleocarpanthraquinone.
- To determine key properties like bond lengths, angles, atomic charges, bond dissociation enthalpies (BDEs), and ionization potential (IP).
Main Methods:
- Density Functional Theory (DFT) was employed.
- B3LYP and M06-2X functionals with 6-31+G(d,p), 6-31++G(d,p), and 6-311+G(d,p) basis sets were used.
- Gas-phase and solvent (water, methanol, ethanol) computations were performed.
Main Results:
- Conformation 5, with extensive hydrogen bonding, was identified as the most stable structure.
- The lowest O-H bond dissociation enthalpy (93.80 kcal/mol) was lower than the ionization potential (146.58 kcal/mol).
Conclusions:
- The hydrogen atom transfer mechanism is favored over single electron transfer for eleocarpanthraquinone's antioxidant potential.
- Computational insights provide a foundation for understanding the reactivity and properties of this compound.
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