LC-MS guided identification of dimeric 2-(2-phenylethyl)chromones and sesquiterpene-2-(2-phenylethyl)chromone conjugates from agarwood of Aquilaria crassna and their cytotoxicity.

Four previously unreported dimeric 2-(2-phenylethyl)chromones (1 – 4a) and three unprecedented sesquiterpene-2-(2-phenylethyl)chromone conjugates (5 – 7), comprising a sesquiterpenoid and a 5,6,7,8-tetrahydroxy-2-(2-phenylethyl)-5,6,7,8 -tetrahydro-4 H -chromone moiety, as well as three known dimeric 2-(2-phenylethyl)chromones (4b , 8a , 8b) were identified from agarwood originating from Aquilaria crassna in Cambodia by LC-MS guided separation. Their structures were elucidated by extensive NMR techniques, HRESIMS and CD. All compounds were evaluated for their cytotoxicity against four human cancer cell lines. Compounds 6 , 7 , 8a , 8b displayed a range of cytotoxic activities with IC 50 values in the rang 10.93–49.0 μM Unlabelled Image [ABSTRACT FROM AUTHOR]