Eckol (1), a novel phlorotannin with a dibenzo-1, 4-dioxin skeleton, has been isolated from the brown alga Ecklonia kurome OKAMURA as a potent and specifif and specific anti-plasmin inhibitor. Its structure has been elucidated based on the spectral data, in particular, by means of negative nuclear Overhauser effect (NOE), and finally established as 1-(3, 5-dihydroxyphenoxy)-2, 4, 7, 9-tetrahydroxydibenzo-1, 4-dioxin by X-ray analysis. Some partially methoxylated derivatives of eckol wre prepared by methylation with diazomethane and also by selective demethylation of eckol permethylate (1b) to establish the structural requirements for inhibitory activities on α2-macroglobulin and α2-plasmin inhibitor, the main plasmin inhibitors in plasma.
Eckol (1)是从褐藻 Ecklonia kurome OK
AMURA 中分离出来的一种具有二苯并-1,4-二恶英骨架的新型绿
单宁,是一种强效、特异性和专一性的抗浆细胞蛋白
抑制剂。根据光谱数据,特别是通过负核奥弗豪泽尔效应(NOE)阐明了其结构,并通过 X 射线分析最终确定其为 1-(3,5-二羟基苯氧基)-2,4,7,9-四羟基二苯并-1,4-二恶英。通过与
重氮甲烷的甲基化反应以及
过甲酸埃克醇(1b)的选择性去甲基化反应,制备了一些埃克醇的部分甲氧基化衍
生物,以确定其对血浆中主要的血浆蛋白酶抑制剂--α2-巨球蛋白和α2-血浆蛋白酶抑制剂的抑制活性的结构要求。