Drimane Sesquiterpenoids from the Mangrove-Derived Fungus Aspergillus ustus

Five new drimane sesquiterpenes (1-5) together with 14 known analogues (6-19) were isolated from laboratory cultures of a mangrove-derived fungus Aspergillus ustus. Their structures were established by spectroscopic methods and antitumor activities were evaluated by sulforhodamine B (SRB) and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) methods.