C-4 or C-12 ethyl substituted 1,5-methanoazocino[4,3-b]indoles, which constitute the tetracyclic framework of uleine alkaloids as well as the ABDE substructure of the Strychnos alkaloid family, have been synthesized by novel 6-exo and 6-endo cyclizations of selenoester-derived 2-indolylacyl radicals upon 5-ethyl-1,2,3,6- and 3-ethyl-1,2,5,6-tetrahydropyridines, respectively.
由C-6或C-12乙基取代的1,5-甲亚
氨基偶氮并[4,3-b]
吲哚构成了油菜碱
生物碱的四环骨架以及Strychnos
生物碱家族的ABDE亚结构,已通过新型6-
硒酸酯衍生的2-
吲哚基甲酰基在5-乙基-1,2,3,6-和3-乙基-1,2,5,6-四氢
吡啶上分别进行exo和6-endo环化反应。