Sampbenzophenones A–G, prenylated benzoylphloroglucinol derivatives from Hypericum sampsonii†
Abstract
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 μM.