Nieuwland Celine, van Well Michiel J, Guillaumes Laia, de Vey Mestdagh Anna, Dekker Lianne, Nieuweboer Cynthia, Simon Sílvia, Fonseca Guerra Célia
Department of Chemistry and Pharmaceutical Sciences, Amsterdam Institute for Molecular and Life Sciences (AIMMS), Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands.
Institut de Química Computacional i Catàlisi, Departament de Química, Universitat de Girona, 17071 Girona, Spain.
Org Biomol Chem. 2025 Aug 1. doi: 10.1039/d5ob00819k.
The aromatic ring in DNA bases affects the Watson-Crick binding strength. Our quantum-chemical analyses, which compare the hydrogen bonding between the DNA bases and unsaturated analogs lacking the aromatic ring, reveal that this arises not from π-resonance assistance but from the electron-withdrawing (purines) or electron-donating (pyrimidines) effect of the heteroatom-containing ring on the frontier atoms. This electron redistribution modulates the electrostatics, steric Pauli repulsion, and σ-orbital interactions upon hydrogen bonding.
DNA碱基中的芳香环会影响沃森-克里克碱基对的结合强度。我们的量子化学分析比较了DNA碱基与不含芳香环的不饱和类似物之间的氢键，结果表明，这种影响并非源于π共振辅助，而是来自含杂原子环对前沿原子的吸电子（嘌呤）或供电子（嘧啶）效应。这种电子重新分布在形成氢键时会调节静电作用、空间泡利排斥作用和σ轨道相互作用。
