Isocoumarins and benzofurans from the mangrove endophytic fungus Talaromyces amestolkiae possess α-glucosidase inhibitory and antibacterial activities. Issue 31 (10th March 2016) - Chen, Senhua
Abstract : Six new isocoumarins, compounds1–4 and14–15, two new benzofurans, 16–17, along with nine known isocoumarin analogues, 5–13 were obtained from the mangrove endophytic fungus Talaromyces amestolkiae YX1. Abstract : Six new isocoumarins, compounds1–4 and14–15, two new benzofurans, 16–17, along with nine known isocoumarin analogues, 5–13 were obtained from the mangrove endophytic fungus Talaromyces amestolkiae YX1. Their structures were elucidated by analysis of spectroscopic data. The absolute configuration of compounds4, 14 and15 were determined by the modified Mosher's method and comparison of their CD spectra with dihydroisocoumarins described in the literature. The structure of compound5 was further confirmed by a single-crystal X-ray diffraction experiment using Cu Kα radiation. Compounds2, 6, 8, and10 showed α-glucosidase inhibitory activity with IC50 values of 89.4, 17.2, 36.4, and 38.1 μM, respectively. In the antibiotic assay, compounds16 and17 exhibited antibacterial activities with MIC values between 25–50 μg mL −1 against the Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, and Bacillus subtilis .