Daldiniaeschsone A, a Rare Tricyclic Polyketide Having a Chromone Unit Fused to a -Lactone and Its Symmetrical Biphenyl Dimer, Daldiniaeschsone B, from an Endophytic Fungus SDBR-CMUNKC745.

Daldiniaeschsone A (), a rare tricyclic polyketide having a chromone unit fused to a -lactone and its symmetrical 6,6'-biphenyl dimer, daldiniaeschsone B (), together with three known compounds (-), were isolated from a plant-derived endophytic fungus, SDBR-CMUNKC745. Their structures were elucidated by extensive 1D and 2D NMR spectroscopic data and HRESIMS. All compounds showed -glucosidase inhibitory activity with IC values ranging from 0.16-0.85 mM and compound was the best -glucosidase inhibitory activity (IC = 0.16 mM).