MP2 study on the hydrogen-bonding interaction between 5-fluorouracil and DNA bases: A,C,G,T

The 5-fluorouracil is a pyrimidine analog effective in the treatment of cancer. In this work, we present the hydrogen-bonding base pairs involving 5-FU bound to the four bases in DNA: adenine, cytosine, guanine, and thymine. Full geometry optimizations have been performed for the studied complexes by MP2 method. The interaction energies were corrected for the basis-set superposition error, using the full Boys-Bernardi counterpoise correction scheme. Hydrogen-bonding patterns of these base pairs were characterized using NBO analysis and AIM analysis. According to the calculated binding energies and structural parameters, the stability of the base pairs decrease in the following order: 5-FU:A > 5-FU:G > 5-FU:T > 5-FU:C.