Abstract
A novel tyroscherin derivative named pseudallecin A (1) with a natural unprecedented morpholine-2, 3-dione structural unit, and a new biogenic synthesis related organic acid named pseudallecin B (2) were purified from a symbiotic fungus Pseudallescheria boydii derived from Pomacea canaliculata. Their structures were elucidated via spectroscopic analyses and ECD calculation. Pseudallecin A exhibited strong inhibitory activities against both Gram-positive Escherichia coli and Gram-negative Staphylococcus aureus.
Graphical Abstract
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Disclosure statement
No potential conflict of interest was reported by the authors.
Supplementary material
Supplementary material relating to this article is available online, alongside HRESIMS, NMR (1 D and 2 D), UV, calculated and experimental ECD spectra and key 2 D NMR correlations of pseudallecins A and B (1 and 2) (Figures S1–S19).