Ly1 cogladines A-H, fawcettimine-type Lycopodium alkaloids from Lycopodium complanatum var. glaucum Ching

摘要

Five new fawcettimine-type alkaloids (1-5) and three new natural products (6-8), along with four known analogues, fawcettimine (9), fewcettidine (10), lycopoclavamine B (11), and lycopladine B (12), were isolated from the whole plant of Lycopodium complanatum var. glaucum Ching. The structures of lycogladines A-H (1-8) were determined based on HRESIMS, 1D and 2D NMR spectroscopic analysis, as well as single-crystal X-ray diffraction. Compound 1 possesses a new ring system that is formed through the linkage of C-13-O-C-2, which is rarely present in Lycopodium alkaloids (LAs). Compounds 1-8 were tested for their beta-site amyloid precursor protein (APP)-cleaving enzyme 1 (BACEI) and acetylcholinesterase (AChE) inhibitory activities. (C) 2018 Published by Elsevier Ltd.