Chemical Constituents of Hypericum petiolulatum.

Chemical study on the methanol extract of aerial parts of Hypericum petiolulatum led to the isolation of one new polycyclic polyprenylated acylphloroglucinol (PPAP), dihroxuralodin ( 1), and one new chromone ( 2), together with four known PPAPs ( 3-6) and nine xanthones ( 7-15). Their structures were established on the basis of spectroscopic data, including IR, MS, 1D, and 2D NMR. All the isolated PPAPs ( 1, 3-6) were evaluated for their cytotoxicity against human prostate cancer cell line PC-3 and human breast cancer cell line MCF-7. Compounds 2 and 7-15 were tested for their antioxidant activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals. Compounds 1 and 3 exhibited moderate cytotoxicity against MCF-7 tumor cell line with IC values of 8.9 and 10.3 μM, respectively. Compounds 2 and 7-15 exhibited potent antioxidant activity with IC values ranging from 5.6 to 36.8 μM, when compared to the positive control, butylated hydroxytoluene (BHT, IC = 78.8 μM). [ABSTRACT FROM AUTHOR]