Characterization of thymol derivatives from Eupatorium fortunei Turcz. aerial parts

From the aerial parts of Eupatorium fortunei, four thymol derivatives (1-4) were isolated and structurally elucidated by NMR and mass spectroscopic methods. Of which, a new dimeric thymol derivative (1) was characterized and its absolute configuration was established by electronic circular dichroism quantum method. In addition, the 1D and 2D NMR as well as HR-ESI mass spectral data of 2 were provided for the first time. Compounds 2-4 were evaluated for their inhibitory activity against α-glucosidase and acetylcholinesterase enzymes. All tested compounds showed weak inhibition at the concentration range of 1–256 μg/mL in both enzymatic assays.