Four new phenylspirodrimane-type dimers, namely chartarlactams Q-T, along with stachyin B were isolated from the fermentation broth of a sponge-derived fungus Stachybotrys chartarum WGC-25 C-6. Chartarlactams Q-T were structurally featured by the dimerization of two units of phenylspirodrimane linked by a C-N bond. Their structures were determined on the basis of extensive spectroscopic analysis, while quantum ECD calculation and modified Mosher's method were used for the assignment of absolute configurations. Chartarlactams Q-S and stachyin B showed moderate inhibition against bacterial pathogen Staphylococcus aureus with MIC values ranging from 4 μg/mL to 16 μg/mL, and chartarlactam T exhibited significant inhibition toward ZIKV virus.
Keywords: Stachybotrys chartarum; antibacterial activity; antivirus activity; chartarlactams Q−T; structure elucidation.
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