The effects of incorporating 2,4-dithiouracil into uracil tetrad: a theoretical study

The geometries of uracil tetrad and other 2,4-dithiouracil incorporated tetrads have been fully optimized at B3LYP/6-31G(d,p) level. The interaction energies and BSSE (basis set superposition error) corrections have been calculated at the same level. The outcomes show that BSSE has great influence on this system and should be considered. With the increasing of the 2,4-dithiouracil numbers, the complex becomes more and more unstable. The structures of the 2,4-dithiouracil incorporated tetrads are incompact as compared with uracil tetrad. The electrostatic potential maps of various tetrads have been plotted and the binding sites and binding strength of the tetrads with metal cations have been predicated.