Lignans and polyacetylenes from Bupleurum acutifolium

Two new lignans (R,Z)-3-(3,4-dimethoxybenzyl)-2-(3,4-dimethoxybenzylidene)-gamma-butrolactone (1) and (2R,3S)-2-acetoxy-2,3-bis(3,4-dimethoxybenzyl)-gamma-butyrolactone (2), and four new polyacetylenes, (2Z,8E, 10E)-heptadeca-2,8, 10-triene-4,6-diyn-1-ol (3), (2E,9Z)-octadeca-2,9-diene-4,6-diyne-1,18-diol (4), (2E,9Z)-18-hydroxy-octadeca-2,9-diene-4,6-diyn-1-yl acetate (5), and (2E,9Z)-1-hydroxy-octadeca-2,9-diene-4,6-diyn-18-yl acetate (6), were isolated and identified from the hexane extract of aerial parts of Bupleurum acutifolium Boiss. Their structures were elucidated by NMR and MS analyses.