Eupholaricanone, a potent α-glucosidase anthracene derivative from Euphorbia larica Boiss

Abstract

A potent α-glucosidase anthracene derivative (eupholaricanone, 1), along with three known compounds lupeol (2) and lupeol acetate (3), and lup 20(29)-ene (4) was isolated as a natural product from ethyl acetate fraction of Euphorbia larica. The structure of the compound was elucidated by 1D (1H- and 13C) and 2D (HSQC, HMBC, COSY and NOESY) nuclear magnetic resonance (NMR) spectroscopy and mass (QTOF-LCMS) spectrometry, and crystal structure was determined by single-crystal X-ray diffraction analysis. In vitro, compound 1 displayed potent α-glucosidase inhibitory activity with 91.60% inhibition and IC50 value of 45.91 ± 0.61 µM. Furthermore, in silico structural bioinformatics tool was employed to predict the binding pattern of compound 1 in the active site of α-glucosidase where compound demonstrated excellent binding interactions with Arg213 and His351 and exhibited higher docking score than the substrate molecule. Our experimental findings and docking results indicate that this anthracene derivative could serve as a lead compound upon optimization.