从产于新疆阿勒泰地区的狭叶白鲜(Dictamnus angustifolius G.Don)的根皮中分得6种柠檬苦素类(limonoids)及其降解产物。其中5种经化学和光谱方法分别鉴定为梣皮酮(fraxinellone,Ⅰ),黄柏内酯(obacunone,Ⅱ),柠檬苦素(limonin,Ⅲ),柠檬苦素地噢酚(limouin diosphenol,Ⅳ)和白鲜二醇(dictamdiol,Ⅴ)。白鲜二醇为一种新的柠檬苦素类天然降解产物,用~1H-~4H COSY 谱等 NMR 方法推定其结构。 Six kinds of limonoids and their degradation products were obtained from the root bark of Dictamnus angustifolius G. Don produced in Altay, Xinjiang. Five of them were chemically and spectroscopically identified as froxinellone (I), obacunone (II), limonin (III), and limoin diosphenol (IV). White diol (dictamdiol, V). Baixin glycol is a new natural degradation product of limonoids, and its structure was estimated by NMR methods such as ~1H-~4H COSY spectrum.