Interaction of adenine with synthetic receptors: a theoretical study
The interaction of adenine with synthetic macrocyclic receptors has been modelled using, as simplified molecular systems, the monoamide derivatives of pyridine and 1,8-naphthyridine. DFT methods (B3LYP/6-31+G**) have been used to characterise the complexes stabilised by multiple hydrogen bonds. The theoretical results indicate that while the synthetic receptors with pyridines can interact simultaneously forming pseudo-Watson–Crick and pseudo-Hoogsten complexes with adenine, in the case of the 1,8-naphthyridines only one of the complexes is possible. The energetic results that favour the pyridine receptors are in agreement with the experimental binding constants.