Hymoins A–C, three unusual polycyclic polyprenylated acylphloroglucinols with lipid-lowering activity from Hypericum monogynum

• Published in: Chinese chemical letters 2024-04, p.109859, Article 109859
• Main Authors: Yuan, Chunmao, Zeng, Yanrong, Huang, Lei, Mou, Yu, Jin, Jun, Yi, Ping, Li, Yanmei, Hao, Xiaojiang
• Format: Article
• Language: English
• Subjects: Hypericum monogynum Polycyclic polyprenylated acylphloroglucinols Structure elucidation Lipid-lowering activity Mechanistic study
• ISSN: 1001-8417; 1878-5964
• DOI: 10.1016/j.cclet.2024.109859

Hymoins A–C (1–3), three unusual polycyclic polyprenylated acylphloroglucinols (PPAPs) were isolated from the flowers of Hypericum monogynum. Hymoin A features the first intriguing 6/5/5/5/7 pentacyclic caged PPAP. Hymoin B is characterized by an unprecedented rearranged 5/6/8 tricyclic ring system, while hymoin C represents the first rearranged PPAP with a fantastic spirocyclic 5/6/7 ring system. Their structures were established by extensive spectroscopic analysis, X-ray crystallography, and computational methods. The plausible biosynthetic routes for the compounds were also proposed. In oleic acid (OA)-induced HepG2 cells, all compounds exhibited significant lipid-lowering activity at the concentrations of 2–8 μmol/L. Further mechanistic study implied that compound 1 exhibited excellent lipid-lowering activity in OA-induced HepG2 cells through inhibiting the proteins of free fatty acids synthesis and improving lipidolysis. [Display omitted] Hymoins A–C (1–3), three unusual polycyclic polyprenylated acylphloroglucinols (PPAPs) were isolated from the flowers of Hypericum monogynum. Compound 1 exhibited excellent lipid-lowering activity in OA-induced HepG2 cells through inhibiting the proteins of free fatty acids (FFAs) synthesis and improving lipidolysis.