Neuropyrones A–E, Five Undescribed Α-Pyrone Derivatives with Tyrosinase Inhibitory Activity from the Endophytic Fungus Neurospora Dictyophora WZ-497

Five undescribed alpha-pyrone derivatives, named neuropyrones A-E, were isolated from the endophytic fungus Neurospora dictyophora WZ-497 derived from the stems of Aster tataricus L. f. The structures of these alpha-pyrones with absolute configurations were determined by comprehensive spectroscopic analysis and computational calculations. All isolated compounds were tested for various bioactivities, including tyrosinase inhibitory ac-tivity. The results showed that neuropyrones A-C displayed potent inhibitory effects on tyrosinase with IC50 values of 0.38 +/- 0.07, 0.49 +/- 0.06, and 0.12 +/- 0.01 mM, respectively, which were comparable to that of the positive control, kojic acid (IC50 = 0.14 +/- 0.021 mM). A molecular docking study revealed the interaction be-tween 3 and the His263, His85, Val283, Asn260, Phe264, and Val248 residues of tyrosinase.