Alkaloids from endophytic fungus <i>Aspergillus fumigatus</i> HQD24 isolated from the Chinese mangrove plant <i>Rhizophora mucronata</i>

Abstract

Chemical investigation of endophytic fungus <i>Aspergillus fumigatus</i> HQD24, isolated from the flower of <i>Rhizophora mucronata</i> led to the isolation of eight alkaloids, including pyripyropene A (<b>1</b>), 1,11-dideacetyl-pyripyropene A (<b>2</b>), pyripyropene E (<b>3</b>), chaetominine (<b>4</b>), tryptoquivaline J (<b>5</b>), fumitremorgin C (<b>6</b>), 1-acetyl-β-carboline (<b>7</b>), and nicotinic acid (<b>8</b>). Their structures were unambiguously elucidated on the basis of extensive spectroscopic data and comparison with the data of literature. Compound <b>2</b> was known as a synthetic product and isolated as a natural product for the first time. The immunosuppressive and cytotoxic activities of all isolated compounds were evaluated.