Two new 2-(2-phenethyl)chromone derivatives from agarwood of Aquilaria walla and their cytotoxicity

Two new 2-(2-phenethyl)chromone derivatives were isolated from agarwood of Aquilaria walla, including a dimeric 2-(2-phenethyl)chromone (1) and a flavonoid-2-(2-phenethyl)chromone (2). Their structures were established based on spectroscopic methods including HRESIMS, 1D, and 2D NMR. Compounds 1 and 2 showed cytotoxic activity against five human cancer cell lines with IC50 values ranging from 4.96?44.34 ?M.