Polyisoprenylated benzoylphloroglucinol derivatives from Hypericum scabrum

Abstract Four new polyisoprenylated benzoylphloroglucinol derivatives, hyperscabrones J–M ( 1 – 4 ), were isolated from the air-dried aerial parts of Hypericum scabrum . Their structures were elucidated by spectroscopic methods and were subsequently confirmed by comparing with data of known compounds. The absolute configuration of the bicyclo[3.3.1]nonane-2,4,9-trione core was defined by the experimental and calculated electronic circular dichroism (ECD) spectra. The evaluation of their hepatoprotective activities against paracetamol-induced HepG2 cell damage showed that compounds 2 and 4 exhibited significant hepatoprotection at 10 μM.