Four new guaiane sesquiterpenoids from agarwood of Aquilaria filaria

Abstract Six 8,12-epoxyguaiane sesquiterpenes ( 1 – 6 ), together with two known 2-(2-phenylethyl)chromone derivatives ( 7 – 8 ) were isolated from agarwood originating from Aquilaria filaria . Their structures were established by spectroscopic methods including IR, HRESIMS, 1D, and 2D NMR, and comparison with the published data. The absolute configuration of compound 1 was unambiguously determined by quantum chemical calculation of the electronic circular dichroism (ECD) spectrum. All compounds were tested for their α -glucosidase inhibitory activity and cytotoxicity. Compound 5 showed significant α -glucosidase inhibitory activity with IC 50 value of 253.2 ± 9.7 μM (Acarbose, 743. 4 ± 3.3 μM). Compounds 2 – 4 displayed weak cytotoxicity against K562 tumor cell lines.