Fluorinated derivatives of tetrahydroaltersolanol molecule on COVID-19, HIV, and HTLV protease by DFT and molecular docking approaches.

Structural, optoelectronic, and biological properties of tetrahydroaltersolanol (CHO) and fluorinated derivatives are calculated using density functional theory (DFT) and molecular docking approaches. It is shown that the pure CHO molecule has a direct HOMO-LUMO energy gap about 3.1 eV. The substitution of F atom at A category decreases the electronic energy gap, while it is constant at B category. In A category, the behavior of the pure molecule changed from insulator to semiconductor with various substitution of F atom. The electronic properties were depended on the F sites in the pure molecule. The molecular electrical transport properties and charge-transfer possibilities increase with decreasing energy gap. The pure CHO molecule with high energy gap has low chemical reactivity and substitution of F atom at considered molecule increases chemical reactivity. Obtained results show that F-O bonds in trifurcation bonds of CHO(F14), CHO(F16), and CHO(F17) molecules play a key role in confronting with COVID-19, HIV, and HTLV proteases, respectively. Optical spectra, such as the dielectric functions, electron energy-loss spectroscopy, refractive index, extinction coefficient, and reflection spectra show that fluorinated derivatives of CHO at B category can be used in the new drugs.