Two phthalides from Ligusticum chuangxiong

Two novel phthalides, (E)-senkyunolide E and senkyunolide N, along with the 18 phthalides including senkyunolide H and senkyunolide J, were isolated from the rhizomes of Ligusticum chuangxiong. On the basis of spectral analyses and chemical methods the structures of (E)-senkyunolide E and senkyunolide N were proved to be (E)-(9RS)-3-butylidene-9-hydroxyphthalide and (3S,6S,7S)-3-butyl-4,5-dihydro-6,7-dihydroxyphthalide, respectively. The absolute configuration of senkyunolide J was also established by spectral analyses and chemical methods; theconformational structure of senkyunolide H was studied by X-ray diffraction analysis.