Isolation, Identification, and α-Glucosidase Inhibitory Activity of the Chemical Composition of Daphne genkwa

Phytochemical investigation of Daphne genkwa led to the isolation and identification of one previously undescribed indole alkaloid (1) and twenty-three known compounds. The isolated compounds were categorized as follows: three alkaloids (1–3), eight yuanhuacin derivatives (4–11), seven lignans (12–18), five flavonoids (19–23), and one monoterpene (24). The structure of the new indole alkaloid (1) was elucidated through comprehensive spectroscopic analysis, including UV, HRESIMS, and 1D/2D NMR techniques. All isolated compounds were evaluated for their α-glucosidase inhibitory activity. Among them, compounds 11, 20, and 23 exhibited moderate inhibitory effects, with IC50 values of 13.39, 16.64, and 18.04 μM, respectively. These findings suggest that certain constituents of D. genkwa might hold potential as α-glucosidase inhibitors, warranting further investigation into their therapeutic applications.