New α-glucosidase inhibitors from a marine sponge-derived fungus, Aspergillus sp. OUCMDZ-1583

18 new compounds named aspergones A–Q and 6-O-demethylmonocerin, along with five known analogues, were isolated from the fermentation broth of Aspergillus sp. OUCMDZ-1583 associated with an unidentified marine sponge from the Xisha Islands of China.