Interaction energy studies on antibiotics nucleoside analogs 2-azaadenine

The 2-azaadenine antibiotic is known to be a potent cytotoxic nucleoside analog. Evaluation of the interaction energy of this molecule with nucleic acid bases and base pairs has been performed using a quantum-mechanical perturbation technique. Both in-plane and stacking energies have been computed. These energy values along with their sites of association have been compared with the standard energy values and spatial positions for the nucleic acid bases during transcription. The results have been examined in the light of their biological significance.