Potent phenolics with antimigratory and anti-MRSA powers from fungus associated with <i>Saussurea involucrata</i>

Seven phenolics were isolated from the endophytic fungus Alternaria sp. associated with Saussurea involucrata. The structures were identified as (±)-Dehydroaltenusin (1), Alterlactone (2), Altenuene (3), Djalonensone (4), 1-Deoxyrubralactone (5), Altertenuol (6), and Alternariol (7) respectively by a combination of spectroscopic and single-crystal X-ray diffraction analysis. Compound 1 showed obvious antimigratory activity against MCF-7 cells. Compound 2 showed potent antibacterial activities against a resistant bacterium Staphilococcus aureus 5 (MRSA). Meanwhile the cytotoxic, antioxidant were also evaluated.