2′,4′,5,7-Tetrahydroxyisoflavone was partially benzoylated with benzoyl chloride to give 7-benzoyloxy-2′, 4′,5-trihydroxyisoflavone. The condensation of the 7-(benzoyloxy)isoflavone with 2-methyl-3-buten-2-ol, followed by the hydrolysis of the resultant 3′-(3-methyl-2-butenyl)isoflavone gave licoisoflavone A. Its 5′-(3-methyl-2-butenyl) isomer was also synthesized from 5-benzoyloxy-2′,4′,7-trihydroxyisoflavone in a similar manner.
用
苯甲酰氯对 2′,4′,5,7-四羟基异
黄酮进行部分苯甲酰化,得到 7-苯甲酰氧基-2′,4′,5-三羟基异
黄酮。将 7-(苯甲酰氧基)异
黄酮与
2-甲基-3-丁烯-2-醇缩合,然后
水解生成 3′-(3-甲基-
2-丁烯基)异
黄酮,就得到了地衣异
黄酮 A。它的 5′-(3-甲基-
2-丁烯基)异构体也是用类似的方法从 5-苯甲酰氧基-2′,4′,7-三羟基异
黄酮合成的。