Bioactive steroidal alkaloids from Buxus macowanii Oliv
Cheuk W Lam1, Andrew Wakeman2, Abin James2
1Department of Chemistry, Richardson College for the Environmental and Science Complex, The University of Winnipeg, 599 Portage Avenue, Winnipeg, MB R3B 2G3, Canada; Department of Chemistry, The University of Manitoba, Winnipeg, MB R3T 2N2, Canada.
Abstract:
Chemical investigation of the crude methanolic extract of Buxus macowanii resulted in the isolation of five new steroidal alkaloids, 31-hydroxybuxatrienone (1), macowanioxazine (2), 16α-hydroxymacowanitriene (3), macowanitriene (4), macowamine (5), along with five known steroidal bases, Nb-demethylpapillotrienine (6), moenjodaramine (7), irehine (8), buxbodine B (9) and buxmicrophylline C (10). Structures of compounds 1-10 were elucidated with the aid of spectroscopic methods including 1D and 2D NMR techniques and mass spectrometry. Compounds 1, 3, and 4 belong to a rare class of Buxus alkaloids having Δ(1,2) 9(10→19) abeo triene system. All isolates were evaluated for in vitro acetylcholinesterase (AChE) inhibitory activity and found to exhibit moderate to weak anti-AChE activity with IC50 values in the range of 10.8-98μM. Compounds 1 and 6 were also moderately active in BACE1 inhibitory assay.
More Related Videos
07:20Author Spotlight: Integrating Traditional Chinese Medicine with Modern Pharmacology and Genomics for Assessing Postmenopausal Osteoporosis in Mice
Published on: August 23, 2024
09:36Author Spotlight: Discovering New Alkaloids in Plants with Advanced Mass Spectrometry Techniques
Published on: March 8, 2024
Related Concept Videos
Direct-Acting Cholinergic Agonists: Chemistry and Structure-Activity Relationship
The direct-acting...
Drugs that Stabilize Microtubules
Direct-Acting Cholinergic Agonists: Pharmacokinetics
Drugs Acting on Autonomic Ganglia: Blockers
Drugs Acting on Autonomic Ganglia: Stimulants
Ganglionic stimulants activate NM nicotinic receptors in autonomic ganglia, falling into two categories: nicotine mimetics [e.g., lobeline, dimethylpiperazine, tetramethylammonium] and muscarinic receptor agonists [e.g., muscarine, methacholine]. The first category's action is rapid and blocked by nicotinic receptor antagonists, while the second category's action is delayed and blocked by atropine-like agents. Nicotine, an alkaloid, affects the heart rate by stimulating...
Opioid Receptors: Overview
