Bioactive steroidal alkaloids from Buxus macowanii Oliv

Area of Science:

• Natural Product Chemistry
• Medicinal Chemistry
• Pharmacology

Background:

• Buxus macowanii is a plant source of bioactive steroidal alkaloids.
• Steroidal alkaloids are investigated for their therapeutic potential, particularly in neurological disorders.

Purpose of the Study:

• To isolate and characterize novel steroidal alkaloids from Buxus macowanii.
• To evaluate the in vitro inhibitory activities of these compounds against acetylcholinesterase (AChE) and BACE1.

Main Methods:

• Phytochemical investigation using spectroscopic methods (1D/2D NMR, MS).
• Isolation and structure elucidation of ten steroidal alkaloids (five new, five known).
• In vitro enzyme inhibition assays for AChE and BACE1.

Main Results:

• Five new steroidal alkaloids (1-5) and five known steroidal bases (6-10) were identified.
• Compounds 1, 3, and 4 feature a rare Δ(1,2) 9(10→19) abeo triene system.
• All isolates showed moderate to weak in vitro AChE inhibitory activity (IC50: 10.8-98μM).
• Compounds 1 and 6 exhibited moderate BACE1 inhibitory activity.

Conclusions:

• Buxus macowanii yields structurally diverse steroidal alkaloids with potential therapeutic applications.
• The isolated compounds demonstrate inhibitory effects against AChE and BACE1, suggesting neuroprotective properties.
• Further research into these alkaloids could lead to novel treatments for Alzheimer's disease.