Geometry, tautomerism and non-covalent interactions of the drug halofuginone with the carbon-nanotube and γ-Fe2O3 nanoparticles: A DFT study

Abstract

Halofuginone is a potential anti-malarial drug, which could exist as three possible tautomers. Herein, using density functional theory (DFT), and handling the solvent effects with the PCM model, the tautomerism of halofuginone was investigated. Intramolecular H-bonds play an important role in the stability of the tautomers. The conformer H1a is the most stable. Noncovalent interactions of the H1a conformer with the armchair (5,5) single-wall carbon nanotubes and γ-Fe 2 O 3 nanoparticles were explored in several manners. The most stable form of them was determined. The intermolecular H-bonds play a substantial role in the energy behavior of the interaction between γ-Fe 2 O 3 nanoparticles and halofuginone.