Chromone Derivatives with α-Glucosidase Inhibitory Activity from the Marine Fungus Penicillium thomii Maire

The fungal strain YPGA3 was isolated from the sediments of the Yap Trench and identified asPenicillium thomii. Eight new chromone derivatives, named penithochromones M−T (1–8), along with two known analogues,9and10,were isolated from the strain. The structures were established by detailed analyses of the spectroscopic data. The absolute configuration of the only chiral center in compound1was tentatively determined by comparing the experimental and the calculated specific rotations. Compounds7and8represent the first examples of chromone derivatives featuring a 5,7-dioxygenated chromone moiety with a 9-carbon side chain. Bioassay study revealed that compounds6–10exhibited remarkable inhibition against α-glucosidase with IC50values ranging from 268 to 1017 μM, which are more active than the positive control acarbose (1.3 mmol).Keywords:chromone derivatives;structural elucidation;inhibitions on α-glucosidase