title: Lycodine-type alkaloids from Lycopodiastrum casuarinoides and their acetylcholinesterase inhibitory activity.
abstract: Four new lycodine-type alkaloids, namely 16-hydroxyhuperzine B (1), N-methyl-11-acetoxyhuperzine B (2), 8,15-dihydrolycoparin A (3) and (7S,12S,13R)-huperzine D-16-O-β-d-glucopyranoside (4), along with ten known analogues 5-14, were isolated from the whole plant of Lycopodiastrum casuarinoides. The structures of the new compounds were elucidated by means of spectroscopic techniques (IR, MS, NMR, and CD) and chemical methods. Compounds 1 and 2 possessed four connected six-membered rings, while compounds 3 and 4 were piperidine ring cleavage products. In particular, compound 4 was a lycopodium alkaloidal glycoside which is reported for the first time. Among the isolated compounds N-demethylhuperzinine (7), huperzine C (8), huperzine B (9) and lycoparin C (13) possessed significant inhibitory activity against acetylcholinesterase, and the new compound 1 showed moderate inhibitory activity. The structure activity relationships were discussed.
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China.
authors.forename: Dong-Bo
authors.initials: DB
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China. chenjj@lzu.edu.cn.
authors.forename: Jian-Jun
authors.initials: JJ
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China.
authors.forename: Qiu-Yan
authors.initials: QY
authors.lastname: Song
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000, China. npchem@lzu.edu.cn.
authors.forename: Kun
authors.initials: K
authors.lastname: Gao
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism; D000470:Alkaloids / Q000737:chemistry / Q000494:pharmacology*; D002800:Cholinesterase Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D006576:Heterocyclic Compounds, 4 or More Rings / Q000737:chemistry / Q000494:pharmacology*; D020128:Inhibitory Concentration 50; D032502:Lycopodium / Q000737:chemistry*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000470:Alkaloids; D002800:Cholinesterase Inhibitors; D006576:Heterocyclic Compounds, 4 or More Rings; D010936:Plant Extracts; C585001:lycodine; D000110:Acetylcholinesterase