Lactonic Constituents of Angelica glauca

Abstract The structure of a second new dimeric lactone, angelicolide ( 4 ), isolated from the roots of Angelica glauca Edgew., has been assigned by spectroscopy and X‐ray analysis. Angelicolide has been found to be a symmetric dimer of the butylidenephthalide 1 ( E ‐ligustilide).