Sesquiterpenoids from Pilea aquarum subsp. brevicornuta

Four new sesquiterpenoids named pileaterpenes A-D (1-4), together with three known sesquiterpenoids (5-7), were isolated from Pilea aquarum subsp. brevicornuta. The chemical structures of the new compounds were tentatively established by extensive spectroscopic methods and quantum chemical calculations. The absolute configurations of 1-3 were further determined by X-ray crystal diffraction, the modified Mosher's method or ECD calculation method. All isolates but 7 were evaluated their activities against interleukin-8 (IL-8) production in HT-29 cells induced by IL-1 beta. (C) 2020 Elsevier Ltd. All rights reserved.