Eumitrin L: a new xanthone dimer from the lichen Usnea baileyi

We are happy to announce that Dr. Hoang Le Thuy Thuy Trang and colleagues recently published their work entitled “Eumitrin L: a new xanthone dimer from the lichen Usnea baileyi”  in the Journal of Natural Medicines (Springer)

Abstract:

Eumitrin L, a new dimeric xanthone, was isolated from the crude acetone extract of the lichen U. baileyi, together with 13 known compounds, including one dimeric xanthone, five depsidones, two depsides, one dibenzofuran and four monophenolics. Spectroscopic analyses (1D, 2D NMR), compared to related references, were employed for structural elucidation, while DP4 probability and ECD spectrum helped identify the absolute configuration of Eumitrin L. Bioactivity evaluation of the isolated compounds revealed several active tyrosinase inhibitors and significant antioxidants. Among them, protocetraric acid (IC50 37.86 μM) and usnic acid (IC50 15.92 μM) were found to be the most active components. Molecular docking simulation on these two compounds further confirmed their notable activities, based on effective H-bond formation and excellent binding energy with the tyrosinase protein (2Y9X) and DPPH proteins (2CDU and 3RP8), respectively