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Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Conformational analysis of alternariol on the quantum level
Olga Scharkoi1, Konstantin Fackeldey, Igor Merkulow
1Zuse Institut Berlin, Takustr. 7, 14195 Berlin, Germany.
Journal of Molecular Modeling
|March 7, 2013
Summary
Theoretical calculations reveal alternariol's nonplanar structure is influenced by hydroxyl group orientation. Loss of hydrogen bonds causes significant structural twists, potentially aiding DNA strand cutting.
Area of Science:
- Crystallography
- Computational Chemistry
- Molecular Biology
Background:
- Alternariol is a mycotoxin with potential biological activities.
- Understanding the structural properties of alternariol is crucial for elucidating its mechanisms of action.
- Nonplanarity in crystalline structures can significantly impact molecular interactions.
Purpose of the Study:
- To investigate the phenomenon of nonplanarity in crystalline alternariol using theoretical calculations.
- To determine how hydroxyl group orientations affect alternariol's planarity, aromaticity, and structural twists.
- To explore the role of intramolecular hydrogen bonding in stabilizing alternariol's geometry.
Main Methods:
- Density Functional Theory (DFT) calculations were employed.
- Analysis of molecular geometry and electronic structure.
- Investigation of intramolecular hydrogen bond formation and disruption.
Main Results:
- Different hydroxyl group orientations lead to varied degrees of nonplanarity and aromaticity in alternariol.
- The presence of an intramolecular hydrogen bond stabilizes a planar geometry.
- Disruption of this hydrogen bond results in a structural twist exceeding 14°.
Conclusions:
- Alternariol's nonplanarity is a tunable property influenced by hydroxyl group configuration and hydrogen bonding.
- The observed structural flexibility, particularly the twist, may be a key factor in alternariol's DNA strand-cutting activity.
- Theoretical calculations provide valuable insights into the structure-activity relationship of alternariol.
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