Four new indole alkaloids from Plantago asiatica

Four new indole alkaloids, plasiaticines A-D (1–4), together with two known ones, were isolated from the seeds of Plantago asiatica. The structures of the new compounds were elucidated on the basis of comprehensive analysis of spectroscopic data. All compounds were tested for their cytotoxic activity, and all compounds except 4 were tested for their acetylcholinesterase (AChE) inhibitory activities.