Lipopeptide Epimers and a Phthalide Glycerol Ether with AChE Inhibitory Activities from the Marine-Derived Fungus Cochliobolus Lunatus SCSIO41401

A pair of novel lipopeptide epimers, sinulariapeptides A (1) and B (2), and a new phthalide glycerol ether (3) were isolated from the marine algal-associated fungus Cochliobolus lunatus SCSIO41401, together with three known chromanone derivates (4–6). The structures of the new compounds, including the absolute configurations, were determined by comprehensive spectroscopic methods, experimental and calculated electronic circular dichroism (ECD), and Mo2 (OAc)4-induced ECD methods. The new compounds 1–3 showed moderate inhibitory activity against acetylcholinesterase (AChE), with IC50 values of 1.3–2.5 μM, and an in silico molecular docking study was also performed.