Two new pyrone derivatives from the mangrove-derived endophytic fungus sydowii #2B.

Two new pyrone derivatives, 2-(12-hydroxypropyl)-3-hydroxy-methyl-6-hydroxy-7-methoxychromone (), and (±)-pyrenocine S (), together with five known compounds xanthoradone A (), (+)-3,3',7,7',8,8'-hexahydroxy-5,5'-dimethyl-bianthra-quinone (), butyrolactone-I (), pyrenocine A (), and (±)-pyrenocine E () were obtained from the mangrove endophytic fungus sydowii #2B. Their structures were elucidated on the basis of spectroscopic methods, single-crystal X-ray diffraction analysis and comparison data with of literatures. Compounds , , , , and showed cytotoxicities against prostate cancer VCaP cells with IC values of 4.19 ± 1.02, 33.36 ± 1.42, 1.92 ± 0.82, 20.06 ± 2.01, 7.92 ± 0.86, and 10.13 ± 0.88 μM respectively, while compound showed no cytotoxic activity. Compounds , , , and exhibited weak inhibition effects against the production of nitric oxide (NO) in lipopolysaccharide (LPS)-induced RAW 246.7 cells with IC values of 40.15, 28.69, 25.25 and 43.08 μM respectively.