Dibenzofurans from Crataegus oresbia and their lipid-lowering activity

Three new dibenzofurans, 2-hydroxy-3,4-dimethoxydibenzofuran (1), 2,8-dihydroxy-3,4,9-trimethoxydibenzofuran (5) and 2-hydroxy-3,4,6,8-tetramethoxydibenzofuran (6), together with three known dibenzofurans 1-hydroxy-2,3,4-trimethoxydibenzofuran (2), 2-hydroxy-3,4,6-trimethoxydibenzofuran (3) and 1,6-dihydroxy-2,3,4-trimethoxydibenzofuran (4), were isolated from the twigs and leaves of Crataegus oresbia. Their structures were identified by the comprehensive analyses of the physicochemical properties and spectroscopic data (NMR and HR-ESI-MS). Compounds 1-3 showed significant in vitro lipid-lowering activities, especially compound 3 was stronger than simvastatin.