New Isochromane Derivatives from the Mangrove Fungus Aspergillus ustus 094102

Four new isochromane derivatives (1–4) along with the known peniciphenol (5) and ( R)-2-(hydroxymethyl)-3-(2-hydroxypropyl)phenol (6) were isolated from the EtOAc extract of the fermentation broth of the mangrove fungus, Aspergillus ustus 094102. The structures of the new compounds including the absolute configuration were elucidated on the basis of spectroscopic analysis, CD and ECD calculation. Compounds 1 and 2 exhibited α-glucosidase inhibition and anti-oxidation against DPPH radical with IC 50 values of 1.4 mM and 25.7 μM, respectively.