Chemical Constituents and α-Glucosidase Inhibitory Activities of the Leaves of Embelia parviflora—In Vitro and In Silico Studies

Phytochemical investigation of the methanol extract of Embelia parviflora Wall. Ex A. DC. leaves (Primulaceae family) led to the isolation of sixteen compounds including three sterols (1–3), one triterpene (4), four flavonoids (5–8), four megastigmanes (9–12), three phenolic compounds (13–15), and one furan derivative (16). Their chemical structures were determined based on ESI-MS and NMR spectral data. This is the first chemical study of E. parviflora. Compounds 3, 8–13, and 16 were found in the Embelia genus for the first time. Compounds 9–11, 13, and 16 represent the first isolation from the Primulaceae family. In the α-glucosidase activity assay, MeOH extract, compounds 4 and 5 strongly inhibited enzyme α-glucosidase activity. A molecular docking study revealed that compounds 4 and 5 showed different interactions with enzyme α-glucosidase.