中文摘要：

大萼香茶菜Rabdosia macrocalyx（Dunn）Hara系唇形科Labiatae香茶菜属Rabdosia植物，主要分布于安徽、江苏、浙江、江西、福建、湖南、广东、广西和台湾等省，民间用于治疗肿瘤等疾病．从该植物及其变种中分离得到的二萜类化合物具有抗菌消炎及抗肿瘤等多种生理活性。

英文摘要：

On the basis of the investigation on natural product antitumor agents, a new diterpenoid named macrocalyxin J was isolated from the leaves of Rabdosia macrocalyx（Dunn） Hara by silica gel column chromatography. Based on IR, MS, 1H NMR, 13C NMR and 2D NMR spectroscopies, the structure of macrocalyxin J was determined as （ 1 α, 6β, 11β, 14α ） -1,7： 6,20-diepoxy-6,11 -dihydroxy-6,7-seco-ent-kaur-16-ene-7,15 - dione-14-acetate. The antitumor activity of the compound was assayed by MTT method. Macrocalyxin J was shown to have a potency in vitro against the cultures of Hela cells.