Three new sesquiterpenoids from agarwood of Aquilaria crassna.

Three new sesquiterpenoids (1-3), together with two known ones were isolated from the EtOAc extract of agarwood originating from Aquilaria crassna. The new compounds were elucidated on the basis of spectroscopic techniques (UV, IR, MS, 1D and 2D NMR). Compounds 1-5 were isolated from agarwood of A. crassna for the first time. In the acetylcholinesterase inhibition experiment of 2-5, compound 3 showed acetylcholinesterase inhibition activity (IR 42.9±0.6%). Compound 5 expressed antibacterial activities against Staphylococcus aureus and Ralstonia solanacearum with diameter of the inhibition zones of 12.35±0.11mm and 16.90±0.09mm, respectively.