Novel syntheses of murrayaquinone A and furostifoline through 4-oxygenated carbazoles by allene-mediated electrocyclic reactions starting from 2-chloroindole-3-carbaldehyde

被引:54
作者
Hagiwara, H [1 ]
Choshi, T [1 ]
Nobuhiro, J [1 ]
Fujimoto, H [1 ]
Hibino, S [1 ]
机构
[1] Fukuyama Univ, Fac Pharm & Pharmaceut Sci, Grad Sch Pharm & Pharmaceut Sci, Fukuyama, Hiroshima 7290292, Japan
关键词
murrayaquinone A; carbazole-1,4-quinone; furostifoline; furo[3,2-alpha]carbazole; allene; electrocyclic reaction;
D O I
10.1248/cpb.49.881
中图分类号
R914 [药物化学];
学科分类号
100701 ;
摘要
The formal total synthesis of murrayaquinone A (1) and the total synthesis of furostifoline (5) were completed by the construction of 4-oxygenated 3-methylcarbazoles 7 based on a new type of electrocyclic reaction through 2-alkenyl-3-allenylindole intermediates 8 derived from the 2-alkenyl-3-propargylindoles 9, starting from 2-chloroindole-3-carbaldehyde (11). The N,O-bisbenzyloxymethyl group of 16c and 22 underwent a Birch reduction followed by treatment with Triton B to produce the known 4-hydroxy-3-methylcarbazole (7a) and 4-hydroxy-3-methylfuro[3,2-a]carbazole (7b) as precursors of murrayaquinone A (1) and furostifoline (5), respectively, The trifluoromethanesulfonyloxy-3-methylfuro[3,2-a]carbazole (24), prepared from 7b, was subjected to reductive cleavage to provide furostifoline (5).
引用
收藏
页码:881 / 886
页数:6
相关论文
共 32 条
[31]  
WU TS, 1983, HETEROCYCLES, V20, P1267
[32]  
YOGO M, 1991, CHEM PHARM BULL, V39, P328