Secondary metabolites from the Cordyceps-colonizing fungus Aspergillus versicolor ZJUTE2

Two new polyketides versicolorones A-B (1–2), one new diketopiperazine derivative aspergiamide B methyl ester (3), along with twenty known compounds 4–23, were obtained from the EtOAc extract of the Cordyceps-colonizing fungus Aspergillus versicolor ZJUTE2. The structures of 1–3 were established by detailed interpretation of the spectroscopic data and their absolute configurations were established by comparative analyses of the calculated and experimental ECD spectra. In the in-vitro bioassay, compounds 8 and 21 exhibited significant inhibitory activity against the Escherichia coli β-glucuronidase (EcGUS) with IC50 values of 54.73 ± 2.69 and 56.59 ± 1.77 μM, respectively. [Display omitted]