Abstract

The mercaptopurine (MP) anticancer drug was investigated here regarding the tautomeric formations and complexation with an iron (Fe)-doped fullerene cage (FFC). The molecular structures were analyzed by performing quantum chemical calculations in three phases including gas (G), oil (O), and water (W). The values of partition coefficient (LogP) were calculated in this regard. Ten tautomers of MP; T1–T10, were found with the highest stability for one of thio-state tautomers; T2. Moreover, the existence of solvent media helped to make higher stable tautomeric structures in comparison with the gas phase. Next, the complexation of T2 with the FFC yielded three MP@FFC complexes approved by the approach of quantum theory of atoms in molecules (QTAIM). All energies and electronic features indicated the possibility of formation of MP@FFC complexes for approaching two roles of adsorption and sensor function. Finally, the idea of combination with FFC was a proposed way for approaching safer MP.