Method for preparing a 3-deoxy-5-hydroxyanthocyanidin salt having a 4' and/or 7 OH substituent from a corresponding acylated flavanone, by (1) reducing the acylated flavanone in a solvent medium by reaction with an alkali borohydride to form a corresponding flavan not having an OH substituent at the 4 position, and (2) oxidizing the flavan or an acylated or hydrolyzed derivative of the flavan in an organic solvent medium by reaction with a halogenated benzoquinone in the presence of a strong acid and water. Suitable acylated flavanones include acetylated natural flavanones, especially acetylated naringenin and hesperetin.
从相应的酰化类
黄酮酮制备具有4'和/或7个OH取代基的3-去氧-5-羟基花色苷盐的方法,包括(1)通过与碱性
硼氢化物反应在溶剂介质中还原酰化类
黄酮酮以形成相应的类
黄酮,该类
黄酮在4位没有OH取代基,以及(2)在有机溶剂介质中通过与卤代苯醌在强酸和
水的存在下反应氧化类
黄酮或类
黄酮的酰化或
水解衍
生物。适当的酰化类
黄酮包括乙酰化的天然类
黄酮,特别是乙酰化的
柚皮素和
橙皮素。