Modeling Biologically Important NH···π Interactions Using peri-Disubstituted Naphthalenes.
Alexander F Pozharskii1, Olga V Dyablo1, Olga G Pogosova1
1Department of Organic Chemistry, Southern Federal University, Zorge 7, 344090 Rostov-on-Don, Russian Federation.
The Journal of Organic Chemistry
|September 10, 2020
Summary
Researchers studied NH···π interactions using naphthalene derivatives. They found these interactions are strongest with positively charged donors and electron-rich acceptors, with counterions significantly weakening the binding strength.
Area of Science:
- Supramolecular Chemistry
- Chemical Biology
- Computational Chemistry
Background:
- NH···π interactions are crucial for protein structure and molecular recognition.
- Understanding these non-covalent forces is key to designing biomimetic systems.
Purpose of the Study:
- To investigate the properties of NH···π interactions using model compounds.
- To determine factors influencing the strength and geometry of NH···π bonds.
- To explore the impact of counterions on NH···π interactions.
Main Methods:
- Synthesis of 8-aryl and 8-pyrrolyl derivatives of 1-aminonaphthalene.
- Spectroscopic and crystallographic analyses.
- Quantum chemical calculations.
Main Results:
- NH···π binding is enhanced by positively charged NH-donors and electron-rich π-donors (pyrrolyl, hydroxyphenyl).
- Counterions (tetrafluoroborate) significantly weaken NH···π interactions through various mechanisms.
- A record-strong NH···π interaction was observed in 8-(2,5-dimethylpyrrol-1-yl)-N,N-dimethylnaphthalene-1-ammonium tetrafluoroborate.
Conclusions:
- Naphthalene derivatives serve as effective models for studying NH···π interactions.
- Counterion effects play a critical role in modulating the strength of NH···π interactions in ionic systems.
- The findings provide insights into the design of molecules for specific binding and structural stabilization.
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