New Tetramic Acid Derivatives From the Deep-Sea-Derived Fungus <em>Penicillium</em> sp. SCSIO06868 With SARS-CoV-2 M<sup>pro</sup> Inhibitory Activity Evaluation

Front Microbiol. 2021 Sep 27;12:730807. doi: 10.3389/fmicb.2021.730807. eCollection 2021.


Three new tetramic acid derivatives (1-3) and a new polyketide (4) along with eight known compounds (5-12) were isolated from cultures of the deep-sea-derived fungus Penicillium sp. SCSIO06868. Four new structures were elucidated by analysis of one-dimensional/two-dimensional nuclear magnetic resonance (NMR) data and high-resolution electrospray ionization mass spectrometry. Their absolute configurations were established by X-ray crystallography analysis and comparison of the experimental and reported electronic circular dichroism (ECD) values or specific optical rotation. Compound 3 exhibited potent, selective inhibitory activities against Staphylococcus aureus and methicillin-resistant S. aureus with minimum inhibitory concentration values of both 2.5 μg/ml. Also, compound 3 showed weak antiviral activity against severe acute respiratory syndrome coronavirus 2 main protease, which was responsible for the coronavirus disease 2019 pandemic.

PMID:34646250 | PMC:PMC8503681 | DOI:10.3389/fmicb.2021.730807