Quinazolin-4-one Coupled with Pyrrolidin-2-iminium Alkaloids from Marine-Derived Fungus <em>Penicillium aurantiogriseum</em>

Abstract

Three new alkaloids, including auranomides A and B (<strong>1</strong> and <strong>2</strong>), a new scaffold containing quinazolin-4-one substituted with a pyrrolidin-2-iminium moiety, and auranomide C (<strong>3</strong>), as well as two known metabolites auranthine (<strong>4</strong>) and aurantiomides C (<strong>5</strong>) were isolated from the marine-derived fungus <em>Penicillium aurantiogriseum</em>. The chemical structures of compounds <strong>1</strong>–<strong>3</strong> were elucidated by extensive spectroscopic methods, including IR, HRESIMS and 2D NMR spectroscopic analysis. The absolute configurations of compounds <strong>1</strong>–<strong>3</strong> were suggested from the perspective of a plausible biosynthesis pathway. Compounds <strong>1</strong>–<strong>3</strong> were subjected to antitumor and antimicrobial screening models. Auranomides A–C exhibited moderate cytotoxic activity against human tumor cells. Auranomides B was the most potent among them with an IC₅₀ value of 0.097 μmol/mL against HEPG2 cells.

Keywords

• marine-derived fungus
• &lt;em&gt;Penicillium aurantiogriseum&lt;/em&gt;
• quinazolin-4-one
• antitumor