New guaiane and acorane sesquiterpenes in high quality agarwood 'Qi-Nan' from Aquilaria sinensis

摘要

Two new guaiane sesquiterpenes (1-2), one new acorane sesquiterpene (3), along with two known sesquiterpenes (4-5) were isolated from high quality agarwood 'Qi-Nan' originating from Aquilaria sinensis. Their structures were established based on spectroscopic methods including IR, HRESIMS, 1D, and 2D NMR. Compound 1 was a guaiane sesquiterpene lactone, and compound 2 was a guaiane sesquiterpene with a 5/6/7 ring carbon skeleton. Compounds 3 and 4 were acorane-type sesquiterpenes. The two acorane sesquiterpenes (3-4) possess lasting fragrant smell at room temperature. These isolated guaiane and acorane sesquiterpenes showed acetylcholinesterase inhibitory activities in different degrees ranged from 19% to 44% at the concentration of 50 mg/mL. (C) 2016 Phytochemical Society of Europe. Published by Elsevier Ltd. All rights reserved.