Erythrina and Related Alkaloids. Part XXXIX. Synthesis of Highly Dehydrogenated Oxoerythrinan Alkaloids, Erytharbine and Crystamidine.
作者:Yoshisuke TSUDA、Shinzo HOSOI、Fumiyuki KIUCHI、Jun TODA、Ryuzo YAMAMOTO、Takehiro SANO
DOI:10.1248/cpb.41.965
日期:——
2, 3-Dichloro-5, 6-dicyano-1, 4-benzoquinone (DDQ) oxidation of 3, 8-dioxyoerythrinan-1(6)-enes in dioxane gave the ring B dehydrogenated products, the 1, 6-dienones, while oxidation in benzene gave the fully dehydrogenated products, the 1, 6, 10-trienones. The same trienones were obtained by DDQ oxidation of the 1, 6-dienones in bezene. On the contrary, oxidation of the isomeric enone, 3, 8-dioxoerythrinan-1-ene, in either dioxane or benzene gave the ring C dehydrogenated product, the 1, 10-dienone. The 1, 6, 10-trienones were transformed to the highly dehydrogenated 8-oxoerythrinan alkaloids, erytharbine and crystamidine, in racemic forms.
2,3-二氯-5,6-二氰基-1,4-苯醌(DDQ)在二噁烷中氧化 3,8-二氧代赤式-1(6)-烯,得到环 B 脱氢产物 1,6-二烯酮,而在苯中氧化则得到完全脱氢产物 1,6,10-三烯酮。1,6-二烯酮在苯中进行 DDQ 氧化也得到了同样的三烯酮。相反,在二噁烷或苯中氧化异构烯酮 3,8-二氧代赤藓南-1-烯,得到的是环 C 脱氢产物 1,10-二烯酮。1,6,10-三烯酮以外消旋形式转化为高度脱氢的 8-氧代赤藓南生物碱、赤藓灵和隐斯塔脒。