Two new polyacetylenes from the roots of Atractylodes macrocephala

Two new polyacetylenes, (5Z,12E)-14-hydroxytetradeca-5,12-dien-8,10-diyn-1-yl 3-methylbut-2-enoate (1) and 5S, 1'R-(6E,12E)-1-hydroxytetradeca-6,12-dien-8,10-diyn-5-yl 2-methylbutanoate (2), together with two known ones, (2E,8E)-12-β-methylbutyryltetradeca-2,8-diene-4,6-diyne-1,14-diol (3), and (E)-5-[5-(but-3-en-1-yn-1-yl)thiophen-2-yl]pent-2-en-4-yn-1-yl acetate (4) were isolated from the ethyl acetate extract of the roots of Atractylodes macrocephala by various chromatographic methods, such as normal phase silica gel column, MPLC, and semi-preparative HPLC. Their structures were identified by kinds of spectroscopic methods including 1D NMR, 2D NMR, IR, UV, HR-ESI-MS, and ECD. Compound 1 exhibited cytotoxic activities in HepG2 and Huh7 cells with IC₅₀ values of 20.50 ± 2.07 and 19.99 ± 1.35 μM, respectively.