Polyketides with Immunosuppressive Activities from Mangrove Endophytic Fungus Penicillium sp. ZJ-SY2

Nine polyketides, including two new benzophenone derivatives, peniphenone (<b>1</b>) and methyl peniphenone (<b>2</b>), along with seven known xanthones (<b>3</b>-<b>9</b>) were obtained from mangrove endophytic fungus <i>Penicillium</i> sp. ZJ-SY₂ isolated from the leaves of <i>Sonneratia apetala</i>. Their structures were elucidated on the basis of MS, 1D, and 2D NMR data. Compounds <b>1</b>, <b>3</b>, <b>5</b>, and <b>7</b> showed potent immunosuppressive activity with IC₅₀ values ranging from 5.9 to 9.3 μg/mL.