Target isolation of diverse sesquiterpenoid from the stems of Daphne genkwa based on molecular networking

Guiding by LC-MS/MS analysis and the Global Natural Products Social (GNPS) Molecular Networking, three undescribed sesquiterpenoids, stedapgens A–C, and two known analogues were discovered in the barks of Daphne genkwa Sieb. et Zucc. The structures were determined by analysis of their spectroscopic data and quantum-chemical calculations. All the isolated novel compounds were tested for their acetylcholinesterase inhibitory activities with IC50 = 0.754 ± 0.059, 0.696 ± 0.026, and 0.337 ± 0.023 μg/ml. Among them, stedapgen A displayed promising inhibitory activities against AChE, and the binding sites were predicted by molecular docking.