This review discusses the synthetic pathways of an important class of quinolines known as pyrimido[4,5-b]quinoline. Due to their profound range as biologically active compounds, they attracted the attention of medical/organic researchers. The construction of pyrimido[4,5-b]quinolines involved the intermolecular cyclization of diamino chloropyrimidine carbaldehyde and intramolecular cyclization of 2-amino-3-cyanotetra/hexahydroquinoline, 2-aminoquinoline-3-carbonitriles, ester or amide. That class of organic compounds was constructed from the reaction between 2-chloro-3-formylquinoline with amidine, urea, and thiourea. Also, barbituric acid and uracil and their analogous play an important role in synthesizing pyrimidoquinolines via multicomponent reaction strategies (MCR).

中文翻译：

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嘧啶并[4,5-b]喹啉衍生物的合成方法


本综述讨论了一类重要的喹啉类化合物——嘧啶并[4,5-b]喹啉的合成途径。由于其作为生物活性化合物的广泛范围，它们引起了医学/有机研究人员的注意。嘧啶并[4,5-b]喹啉的构建涉及二氨基氯嘧啶甲醛的分子间环化和2-氨基-3-氰基四/六氢喹啉、2-氨基喹啉-3-甲腈、酯或酰胺的分子内环化。这类有机化合物是通过 2-氯-3-甲酰基喹啉与脒、脲和硫脲之间的反应构建的。此外，巴比妥酸和尿嘧啶及其类似物在通过多组分反应策略（MCR）合成嘧啶喹啉中发挥着重要作用。