Phenol Derivatives From the Sponge-Derived Fungus Didymellaceae sp. SCSIO F46.

Seven new phenol derivatives named coleophomones E and F ( 1 , 2 ), diorcinols L and M ( 3 , 4 ), 1-hydroxy-6-methyl-11-methoxy-8-hydroxymethylxanthone ( 5 ), porric acid E ( 6 ), and 7-(2-hydroxyphenyl) butane-7,8,9-triol ( 7 ), were isolated from the EtOAc extract of the marine sponge-derived fungus Didymellaceae sp. SCSIO F46, together with 10 known compounds. Their structures were determined by spectroscopic analyses, including NMR, MS, X-ray diffraction, and theoretical calculations. Each of 1 and 2 contains an unusual spiro [cyclohexane-1,2'-inden] moiety, which is relatively seldom in nature products. Cytotoxic and COX-2 inhibitory activities of all purified compounds were tested and evaluated. Compound 3 displayed obvious cytotoxicities against Huh-7, HeLa, DU145 and HL60 cells (IC50 values 5.7-9.6 μM) and weak activities against other five cell lines, while 8 showed weak cytotoxicities against HeLa and HL7702 cells. Compound 6 displayed COX-2 inhibitory activity with IC50 value of 3.3 μM.