Structural and spectroscopic analysis of indole alkaloids: Molecular docking and DFT approach

Abstract In the present study, a combined theoretical and experimental approach is used to study the structural properties as well as the activity of isoborreverine. Additionally, the results are compared with the previously reported dimethyisoberrevrine. FT‒Raman and FT‒IR spectra were recorded in the solid phase and interpreted in terms of potential energy distribution. Good consistency was found between calculated and observed spectra. Moreover, 1 H and 13 C NMR spectra were recorded and compared with calculated results that were nicely matched. The time-dependent density functional theory is used to find the various electronic transitions and their nature within the molecule. Additionally, the chemical reactivity parameters of isoborreverine have been calculated. The inhibitory activity was analyzed by the comparison of binding energy and binding mode of interaction of isoborreverine and dimethylisoborreverine with the anti-P-glycoprotein. The results indicate that isoborreverine and dimethylisoborreverine have good affinity to anti-P-glycoprotein, and may interact with the catalytic site of the enzyme. Furthermore, the role of C H … N intra-molecular hydrogen bond in the stability of the molecule is investigated on the basis of the topological properties of AIM theory and NBO analysis.