Secondary metabolites from Antarctic marine-derived fungus <i>Penicillium crustosum</i> HDN153086

<p>A new polyene compound (<b>1</b>) and a new diketopiperazine (<b>2</b>), as well as three known compounds (<b>3</b>–<b>5</b>), were isolated from the Antarctic marine-derived fungus <i>Penicillium crustosum</i> HDN153086. The structures of <b>1</b>–<b>5</b> were deduced based on MS, NMR and TD-DFT calculations of specific ECD spectra. These compounds were evaluated for their cytotoxic activities against K562 cell line and only compound <b>2</b> exhibited cytotoxicity against K562 cell, with IC₅₀ value of 12.7 μM.