Polycyclic Polyprenylated Acylphloroglucinol Congeners Possessing Diverse Structures from Hypericum henryi

Area of Science:

• Natural Product Chemistry
• Phytochemistry
• Organic Chemistry

Background:

• Polycyclic polyprenylated acylphloroglucinols (PPAPs) are hybrid natural products with diverse structures and bioactivities.
• PPAPs originate from mevalonate/methylerythritol phosphate and polyketide biosynthetic pathways.
• Hypericum species are known sources of bioactive natural products.

Purpose of the Study:

• To conduct a systematic phytochemical investigation of Hypericum henryi.
• To isolate and characterize PPAP derivatives from H. henryi.
• To explore the structural diversity, biogenesis, and bioactivity of PPAPs.

Main Methods:

• Phytochemical investigation using chromatographic separation techniques.
• Structure elucidation of isolated compounds using NMR spectroscopy.
• Biomimetic synthesis for structural confirmation.
• Bioactivity assays, including acetylcholinesterase inhibition and cytotoxicity testing.

Main Results:

• Isolation of 40 PPAP-type derivatives from Hypericum henryi.
• Identification of 12 distinct structural types of PPAPs, including four unusual skeletons.
• Discovery of nine new compounds, hyphenrones G-Q.
• Revision of the structure of perforatumone to hyphenrone A (5).
• Demonstration of inhibitory activities of several PPAPs against acetylcholinesterase and human tumor cell lines.

Conclusions:

• Hypericum henryi is a rich source of structurally diverse PPAPs.
• The study elucidated the structural diversity and provided insights into the biogenesis of natural PPAPs.
• Several isolated PPAPs exhibit potential as acetylcholinesterase inhibitors and anticancer agents.