Seven prenylated benzoylphloroglucinol derivatives, named sampbenzophenones A-G(1-7), together with two known analogues (8 and 9), were isolated from the aerial parts of Hypericum sampsonii. Their structures were elucidated by a combination of spectroscopic analyses including HRESIMS and NMR. Compound 6 was found to be the first natural product possessing an unusual 6,6-dimethoxy-3-methylhex-2-en-1-oxyl group. These new compounds were evaluated for their cytotoxic activities against five human cancer cell lines, of which, compound 1 exhibited moderate activities with IC50 values ranging from 13.32-29.65 mu M.
基金：
State Education Ministry of China [NCET-2008-0224]; National Natural Science Foundation of China [31370372, 21502057, 81573316]; National Science and Technology Project of China [2011ZX09102-004]; China Postdoctoral Science Foundation [2015M572154]; Fundamental Research Fund for the Central Universities [2016YXMS149]; Program for New Century Excellent Talents in University
