Chemical constituents of the marine-derived fungus AN-13.

Two new compounds named 3()-hydroxy-1-(2,4,5-trihydroxy-3,6- dimethylphenyl)-hex-4-en-1-one () and acremonilactone (), together with nine known compounds (-), were isolated from the fermentation broth of . associated with marine sediments collected from South China Sea. NMR and HRESIMS spectroscopic analysis elucidated the structure of two new compounds. Compound had characteristic rotary gate shape skeleton with a six-membered lactone. Compounds and showed DPPH radical scavenging activity with inhibition rates of 96.50 and 85.95% at the concentration of 0.5 mg/ml, respectively. Moreover, compounds , and showed definite antibacterial activity against ATCC 6538.