Conformational Investigation of the Encapsulation of Nicotinic Acid Into β‐Cyclodextrin

Abstract In the current paper, we report the theoretical study of the ability of the β‐cyclodextrin as encapsulate Vitamin B3 forming the inclusion complex systems. Due to its critical physiological roles, the inclusion phenomenon is increasingly an important area to protect drugs against conjugation and metabolic inactivation. The system ( NA@β‐CD ) formed by 1 : 1 host‐guest stoichiometry of Nicotinic acid (NA) and β‐cyclodextrin ( β‐CD ) was investigated by using the density functional theory when including the dispersion correction with the B97‐D3 functional and 6‐31G* basis set in water using a continuum solvent model ( SMD ) and in a vacuum. In the docking process, two models of complications were assessed. Moreover, in order to examine the quality and the nature of the bond forming during the complexation process, the natural orbital analysis ( NBO ) and Quantum Theory of Atoms in Molecule Analysis ( QTAIM ) were employed. The Non‐Covalent Interaction Analysis ( NCI ) illustrates H‐bonds, Van der Waals and steric repulsion. The Energy Decomposition Analysis ( EDA ) results reveal that dispersion ΔE disp interaction followed by electrostatic attraction ΔE elstat contributes mainly to the attractive terms.