Abstract: Three diterpenoids, compound A (1), B(2) and C (3), have been isolated together with daucosterol (4) from the ethanol extract of Siegesbeckia glabrescens. Their chemical structures have been elucidated as ent-16β,17-dihydroxykauran-19-ocid (1), siegesbeckioside (2), darutoside (3),on the basis of chemical and spectral evidences. Compounds 1 and 2 are isolated for the first time from Siegesbeckia glebrescens.

Key words: Compositae

摘要： 从毛梗希莶（Siebesbeckia Mbrescens）的乙醇提取物中分到胡萝卜甙和3个二蕨类成分，根据光谱和化学证据，3个二萜的化学结构被分别确定为：对映-16p，17-二羟基贝壳杉烷-19-酸（l），腺梗希莶甙（2）和希莶甙（3）。对映二羟基-16β，17-贝壳杉烷-酸和腺梗希莶甙系首次从毛梗希莶中得到。

关键词: 菊科, 毛梗希莶, 对映-6β, 17-二羟基贝壳杉烷-19-酸（1), 腺梗希莶甙（2）, 希莶甙（3）