Four new polyprenylated acylphloroglucinol derivatives from Hypericum beanii .

Two new polycyclic polyprenylated acylphloroglucinols (PPAPs), hyperbeanins P-Q ( 1-2 ), and two new biosynthetic precursors, hyperbeanins R-S ( 3-4 ), were isolated from Hypericum beanii , together with three known analogs ( 5-7 ). Compound 1 was one of type A PPAPs featured with unusual bicyclo[5.3.1]hendecane core. The structures of isolates were established by NMR spectroscopic methods, experimental electronic circular dichroism (ECD) spectra and comparisons with known compounds. Compounds 5 and 6 showed obvious hepatoprotective activity at 10 µM against paracetamol-induced HepG2 cell damage.