DENSITY FUNCTIONAL THEORY STUDIES ON GEOMETRIC AND ELECTRONIC PROPERTIES OF ANTICANCER COMPOUNDS, DNA BASEPAIRS AND THEIR COMPLEXES

Abstract

In the present work, Interaction studies of eight anticancer drugs with the DNA base pairs have been carried out on molecular level using theoretical and computational DFT studies. An investigation of interactions was carried out by analyzing the changes in geometric and electronic parameters of anticancer drugs before and after complex formation with DNA base pairs. Based on these observations the Azonafide and Camptothecin were kept under the category of intercalators and Thioguanine, 5- BromoUracil, Carmustine, Psoralen, Berenil and Pentamidine were kept under the category of non-intercalators. The evaluation of electronic and geometric parameters suggested that 5- BromoUracil is the strongest acceptor with the highest electrophilicity index and least chemical hardness. It was also found that 5- BromoUracil is the most reactive, least stable and hence most potent antitumor drug among all other anticancer drugs under study and Pentamidine was found to be least potent of eight anticancer drugs. It was observed that 5-BromoUracil acted as base pair replacer developing strong covalent interactions with DNA base pairs. However, Pentamidine interacted with base pairs through non covalent mode of interaction. This investigation ultimately leads to elucidate the different anticancer compound classes as potential pharmaceutical groups and therefore, design new anticancer drugs with higher affinity with DNA basepairs