Synthesis of Terpenic Esters Using Natural Kaolinite Clay: Thermodynamic, Kinetic and Bioinformatics Studies

Abstract

This study aims to synthesise novel terpene esters to evaluate their capability to inhibit the Ebola virus. High-value terpene esters were designed and synthesised using local kaolin as an eco-compatible catalyst, with yields ranging from moderate to excellent. Kinetic and thermodynamic studies of the acylation of l-menthol at different temperatures were calculated, revealing the correlations between activation energy, standard Gibbs energy, standard entropy and standard enthalpy. Density Functional Theory (DFT) calculations were performed for a series of terpene esters, and their behaviour was analysed using Frontier Molecular Orbitals (FMO) and Molecular Electrostatic Potential (MEP). Energy gaps for highly active compound 2a and weakly active compound 10a are 0.3508 and 0.4080, respectively. Additionally, the pharmacokinetic properties of selected synthesised compounds were predicted by metabolism, excretion, and toxicity (ADME/T). Molecular docking (in silico) and theoretical calculation explained the action mechanism. According to the results, the tested compounds inhibiting 5GQB represent promising novel drug candidates against the Ebola virus.