A novel approach to the synthesis of substituted 5-amino-4-cyanochromeno[4,3,2-de][1,6]naphthyridine-1-carboxylates from a wide range of substituted 2-hydroxybenzaldehydes with alkyl 3-oxo-3-substituted propanoates and malononitrile was investigated via propionic acid-promoted cascade Knoevenagel condensation/Michael addition/intramolecularly nucleophilic addition accompanied by oxidative aromatization. This procedure provided a highly efficient and facile route to functionalized chromenonaphthyridines from readily available substrates under mild reaction conditions.

中文翻译：

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通过伪四组分反应高效合成铬诺[4,3,2-de][1,6]萘啶衍生物

从广泛的取代 2-羟基苯甲醛与烷基 3-oxo-3合成取代的 5-amino-4-cyanochromeno[4,3,2- de ][1,6] naphthyridine -1-carboxylates 的新方法通过丙酸促进的级联 Knoevenagel 缩合/迈克尔加成/分子内亲核加成伴随氧化芳构化研究 - 取代的丙酸酯和丙二腈。该过程提供了一种高效且简便的途径，可在温和的反应条件下从容易获得的底物获得官能化的色壬萘。