New Polyketide Congeners with Antibacterial Activities from an Endophytic Fungus 17035 (China General Microbiological Culture Collection Center No. 40666).

Four new polyketides, heterocornol Y (), stemphyindan (), pestalospirane C (), and stemphyspyrane (), along with five known ones (-) were isolated from the endophytic fungus 17035 (SG17035) based on the One Strain Many Compounds (OSMAC) strategy allied with an LC-MS approach. These structures were elucidated through extensive spectroscopic analyses, single-crystal X-ray diffraction, and C NMR-DP4 analysis. Pestalospirane C () and stemphyspyrane () featured unprecedented spiroketal skeletons.