中文摘要：

目的研究夹竹桃科植物羊角棉Alstonia mairei枝叶中的非生物碱类化学成分。方法采用硅胶柱色谱、反相硅胶柱色谱和Sephadex LH-20凝胶柱色谱以及制备型高效液相色谱等方法进行分离,采用理化分析以及NMR谱和MS谱等谱学方法鉴定化合物的结构。结果从羊角棉枝叶90%乙醇提取物的石油醚萃取部位中分离得到了18个化合物,分别鉴定为羽扇豆醇（1）、30-醛基羽扇豆醇（2）、羽扇豆醇乙酸酯（3）、α-香树酯醇（4）、α-香树酯酮（5）、23-羟基熊果酸（6）、β-香树酯醇（7）、β-香树酯酮（8）、山楂酸（9）、木栓醇（10）、木栓酮（11）、杨芽黄素（12）、5,6-二羟基-7,4′-二甲氧基黄酮（13）、5,3′-二羟基-7,4′-二甲氧基黄酮（14）、7-羟基-5,3′,4′-三甲氧基黄酮（15）、5,7,3′,4′-四甲氧基黄酮（16）、5-羟基-6,7,8,4′-四甲氧基黄酮（17）和5-羟基-6,7,8,3′,4′-五甲氧基黄酮（18）。结论化合物1为首次从羊角棉中分离得到,其他化合物均为首次从鸡骨常山属植物中分离得到。

英文摘要：

Objective To study the non-alkaloid constituents from the stems and leaves of Alstonia mairei. Methods The chemical constituents were separated and purified by silica gel, ODS, Sephadex LH-20 gel column chromatographies, and preparative HPLC. Their structures were determined by physicochemical properties, spectral data, as well as comparisons with the data in literature. Results Eighteen compounds were isolated from the petroleum ether fraction of 90% ethanol extract from the stems and leaves of A. mairei, and identified as lupeol（1）, 30-oxo-lupeol（2）, lupenyl acetate（3）, α-amyrin（4）, α-amyrenone（5）, 23-hydroxyursolic acid（6）, β-amyrin（7）, β-amyrenone（8）, maslinic acid（9）, friedelinol（10）, friedelin（11）, tectochrysin（12）, 5,6-dihydroxy-7,4′-dimethoxyflavone（13）, 5,3′-dihydroxy-7,4′-dimethoxyflavone（14）, 7-hydroxy-7,5,3′,4′-trimethoxyflavone（15）, 5,7,3′,4′-tetramethoxyflavone（16）, 5-hydroxy-6,7,8,4-tetramethoxyflavone（17）, and 5-hydroxy-6,7,8,3′,4′-pentamethoxyflavone（18）. Conclusion All compounds are isolated from A. mairei for the first time. In addition to compound 1, the other compounds are isolated from the plants of Alstonia R. Br. for the first time.