Prenylated acylphloroglucinols from the fruits of Garcinia xanthochymus

Our continuous study of the dry fruits of Garcinia xanthochymus led to the isolation and structural characterization of four new prenylated acylphloroglucinols, xanthochymusones J–M (1–4), together with the known polycyclic polyprenylated acylphloroglucinols, garciniagifolone A (5) and garcinialiptone A (6). Their structures were elucidated by interpretation of NMR and MS spectroscopic data. Compound 1 bearing a similar core to that of hulupinic acid should be derived via oxidization and ring contraction of prenylated acylphloroglucinol. The inhibitory activities of all the compounds against three human hepatocellular carcinoma cell lines Huh-7, Hep 3B, and Hep G2 were evaluated, and compounds 4 and 5/6 exhibited moderate cytotoxic activities against Hep G2 cells with IC50 values10.4 and 8.8 μM.