【摘要】 <正> 夏天无[Corydalis decumbens（Thunb）Pers]为常用中草药之一,主要产地为我国的江西和安徽.药用部位为块根,性味苦良,民间用于治疗高血压偏瘫和风湿性关节炎等症.近年来,夏天无眼药水用于治疗青少年假性近视眼效果显著,引起了国内外学者的兴趣.从夏天无中已分得了新生物碱——夏天无碱乙素,新天然产物——白毛茛碱宁和脱氢白毛茛碱宁以及其它十多个已知成分.近又从中分得一新生物碱——夏天无碱丙素（1）. 1为棕色丛毛状结晶,高分辨质谱定分子式为C₁₉H₁₁NO₆（M⁺349.0548）.紫外吸收峰和papaverine相似,红外光谱示五元环内酯(1760cm^-1),次甲二氧基(940cm^-1).根据紫外更多还原

【Abstract】 A new phthalide isoquinoline alkaloid with an unusual ring B structure decumbenine-C, isolated from the roots of Corydalis decumhens （Thunb） Pers, a traditional Chinese medicinal herb is reported. Decumbenine-C, C₁₉H₁₁NO₆, m. p. 211—213℃, forms brown woolly crystal. Its structure was established by a combination of UV, IR and ¹H NMR spectral study and shown in the Chinese text. Every proton in decumbenine-C was assigned by a combination of the double irradiation and NOED spectral studies. Three mg of decumbenine-C was isolated from 150g of the crude alkaloid.更多还原