Unusual derivatives from Hypericum scabrum

Area of Science:

• Natural Product Chemistry
• Medicinal Chemistry
• Phytochemistry

Background:

• Hypericum species are known sources of bioactive compounds.
• Exploring novel chemical entities from medicinal plants is crucial for drug discovery.

Purpose of the Study:

• To isolate and characterize new compounds from Hypericum scabrum.
• To evaluate the antiprotozoal and cytotoxic activities of the isolated compounds.

Main Methods:

• Isolation via n-hexane extraction.
• Structure elucidation using extensive spectroscopic (NMR, HRESI-TOFMS) and spectrometric techniques.
• Absolute configuration determination via ECD calculations and single crystal X-ray diffraction.

Main Results:

• Three new compounds (1-3) with unusual skeletons were identified.
• Compound 1: First esterified polycyclic polyprenylated acylphloroglucinol with a tricyclo-[4.3.1.1^1,4]-undecane skeleton.
• Compound 2: MPAP with a cycloheptane ring and prenyl substituents.
• Compound 3: Possesses a 5,5-spiroketal lactone core.
• Compound 1 exhibited moderate in vitro activity against Trypanosoma brucei rhodesiense (IC₅₀ 3.07 μM) and Plasmodium falciparum (IC₅₀ 2.25 μM).

Conclusions:

• The study successfully isolated and characterized three novel compounds from Hypericum scabrum.
• The findings highlight the potential of Hypericum scabrum as a source of structurally unique and biologically active natural products.
• Compound 1 shows promise for further investigation as an antiprotozoal agent.