Abstract: Z-Ligustilide (1) and sedenenolide (2)are important naturally 3-alkylphthalide analogues occurring in many plants belonging to the Umbelliferae.They have antispasmodic antiasthmatic and smooth muscle relaxing activities.Herein the synthesis of(±)-sedenenolide (2) is described,starting from phthlic anhydride as starting material,The key step in the synthesis is the Birch reduction of 3Z-butylidenephthalide, 3-methyloxy-3-butylphthalide (4)and methyl o-valerybenzoate(3).The yield in this step is 44%-60%. The synthesis of ligustilide (1) was studied.

Key words: Ligustilide, Sedenenolide, 3Z-Butylidenephthalide