自苦木科植物苦木的木质部分离得到四个生物碱,经UV,IR,NMR和MS分析和物理化学常数测定,确定其中两个为新的β-咔巴啉生物碱,分别命名为苦木碱辛和苦木碱壬.苦木碱辛的结构为1-甲酰基-4-甲氧基-β-咔巴啉(1),苦木碱壬的结构为1-甲氧丙酰基-β-咔巴啉(2).另外两个为已知生物碱1-乙烯基-4-甲氧基-β-咔巴啉(3)和3-甲基铁屎米-2,6-二酮(4) Four plant alkaloids were isolated from the xylem of bitter wood of bitter woody plant. Two of them were determined as new β-carboline alkaloids by UV, IR, NMR and MS analysis and physicochemical constants, respectively named as bitter Aconitine and misoprostone.The structure of aconitine is 1-formyl-4-methoxy-β-carboline (1), and the structure of acomyl is 1-methoxypropionyl- β-carbazole (2). The other two are known alkaloids 1-vinyl-4-methoxy-β-carboline (3) and 3- Ketone (4)