描述了在碱性水介质中通过简单有效的环缩合反应,由亚芳基巴比妥酸和各种氨衍生物如盐酸苯肼,盐酸羟胺和氨基胍盐酸盐合成含氮杂环的方法。这种改进的绿色合成方法提供了一种方便的直接方法,该方法使用水作为绿色溶剂,并使用碳酸钾(K 2 CO 3)作为绿色碱,以优异的产率合成吡唑并嘧啶,异恶唑并嘧啶和嘧啶并嘧啶。
Abstractmagnified imageThe present investigation provides a simple and convenient route for the synthesis of substituted 5‐deaza‐10‐oxaflavins owing to their importance as probable redox coenzymes. The reaction of α,β‐unsaturated derivatives of barbituric acid and dimedone with catechol or 1,4‐hydroquinones was catalyzed using laccase in aqueous medium. Quinones, generated in situ by the oxidation of the corresponding catechol or 1,4‐hydroquinones, underwent a domino reaction with chalcones to produce 5‐deaza‐10‐oxaflavins and tetrahydroxanthen‐1‐ones.