7-methylenedioxy-isoquinoline (21) gave 10-methoxy-2,3-methylenedioxy-13aα-berbine-9,13β-diol (33) and the isomeric 11,13β-diol (34). 9-O-Methylation of the diol (33) gave (±)-ophiocarpine (3). A general synthesis of 13-hydroxy-berbines from 1,2,3,4-tetrahydro-α-hydroxybenzylisoquinolines by Mannich reaction and phenolic cyclisation is described.
(1 R *)-1-[((α,R *)-α,3-二羟基-4-甲氧基苄基] -1,2,3,4-四氢-6,7-亚甲基二氧基-
异喹啉的
酚类环化反应(21)得到10-甲氧基-2,3-亚甲二氧基-13aα-小b碱-9,13β
-二醇(33)和异构体11,13β
-二醇(34)。二醇(33)的9- O-甲基化得到(±)-
邻苯二酚(3)。描述了由1,2,3,4-四氢-α-羟基苄基
异喹啉通过曼尼希反应和
酚环合反应合成13-羟基-小bin碱的一般方法。