Talaromyolides A–D and Talaromytin: Polycyclic Meroterpenoids from the Fungus Talaromyces sp. CX11

Talaromyolides A–D ( 1 – 4 ) and talaromytin ( 5 ) were isolated from a marine fungus Talaromyces sp. CX11. Their structures were unambiguously determined by nuclear magnetic resonance (NMR), mass spectrometry, X-ray crystallography experiments, and time-dependent density functional theory electronic circular dichroism calculations. Talaromyolides A and D represent two novel carbon skeletons. Talaromytin exhibits two slowly interconverting conformers in DMSO- d 6 and CH 3 OH- d 4 that were studied by temperature-dependent NMR experiments. Talaromyolide D exhibits potent antiviral activity against pseudorabies virus (PRV) with a CC 50 value of 3.35 μM.