6,7-二乙酰氧基黄芩素的一步合成、选择性水解及甲醚化

One-step Synthesis,Selective Hydrolysis and Methoxylation of 6,7-Diacetoxylbaicalein

以黄芩中的主要活性成分黄芩苷为原料,在醋酸钾、吡啶催化回流条件下,用醋酐为乙酰化试剂,以67.6%的收率实现了6,7-二乙酰氧基黄芩素一步合成,该化合物经K2CO3/丙酮-水条件下的水解反应或Me2SO4/K2CO3/丙酮中的甲醚化反应以良好收率及高选择性分别得到6-乙酰氧基黄芩素或7-甲氧基-6-乙酰氧基黄芩素。

6,7-Diacetoxylbaicalein was synthesized in a yield of 67. 6% by direct acetylation of baicalin, the main active component of a traditional Chinese herb Scutellaria baicalensis Georgi, with acetic anhydride catalyzd using CH3 COOK/Py under reflux. The monoacetylated derivative 6-acetoxyl baicalein or mono-O- methylated derivative 6-acetoxy-7-methoxylbaiealein was prepared in an excellent yield from 6,7-diacetoxylba- icalein via a high selective hydrolysis reaction in the presence of K2 CO3/acetone-H2 0 or a methoxylation reaction at the C-7 position with Me2SO4, respectively.