“一锅法”制备乙酰灯盏乙素苷元

One-pot synthesis of acetyl scutellarein from scutellarin

目的探索制备乙酰灯盏乙素苷元的方法。方法以灯盏乙素为起始原料,与乙酸酐和吡啶共回流,经一步反应获得四乙酰灯盏乙素苷元和部分乙酰化产物6,7,4'-O-三乙酰基灯盏乙素苷元。结果与结论采用"一锅法"合成了乙酰灯盏乙素苷元,总收率在80%以上。乙酰灯盏乙素苷元和其乙酰化产物6,7,4'-O-三乙酰基灯盏乙素苷元均是灯盏乙素结构改造和修饰的重要中间体。与现有的两步合成法相比,本方法具有合成路线短、收率高、反应条件简单等特点,该法为同时获得2个重要中间体提供了有价值的参考。

Acetyl scutellarein was an important intermediate in the modification of scutellarin. Acetyl scutel- larein was prepared formerly by two steps,including hydrolysis and acetylation. The total yield was no more than 70% because of the instability of scutellarin under the condition of hydrolysis. Here a one-pot synthesis of acetyl scutellarein from scutellarin was reported. Scutellarin was refluxed with acetic anhydride and pyridine and then purified by silica gel column chromatography to yiled 5,6,7,4＇-O-tetraacetylscutellarein （3） and 6,7,4＇-O-triacetylscutellarein （4）. Both of the two products were important intermediates in the modification of scutellarin. Total yield of the two intermediates was more than 80%.