Dimeric sesquiterpenoid-4H-chromone derivatives from agarwood of Aquilaria crassna and their cytotoxicity

Abstract Six previously undescribed uncommon ester-bonded dimeric compounds (aquilacrassnins A–F) containing a sesquiterpenoid and a 5,6,7,8-tetrahydroxy-2-(2-phenylethyl)-5,6,7,8-tetrahydro -4 H -chromone units were isolated from the EtOAc extract of agarwood originating from Aquilaria crassna . Their structures were elucidated by spectroscopic (NMR, UV, IR, MS, and ECD) methods. All the compounds were tested for AChE inhibitory activity and cytotoxicity against K562, BEL-7402, SGC-7901, Hela, and A549 tumor cell lines. The results showed that aquilacrassnin A, B, and E exhibited weak cytotoxicity against the five tested cell lines, whereas all the compounds were inactive against AChE.