A simple and useful protocol leading to different 4H-pyrido[1, 2-a] pyrimidin-4-ones have been established by cyclization of various 2-amino pyridines with β-oxo ester or alkynoate. The use of ethylene glycol was demonstrated to facilitate this condensation. This reaction proceeds by nontoxic, cheap, environment friendliness and biodegradable solvent at the normal green atmospheric condition in the absence of catalyst.

中文翻译：

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以乙二醇为促进剂的4 H-吡啶并[1，2- a ]嘧啶-4-酮的实用合成

通过将各种2-氨基吡啶与β-氧代酸酯或炔酸酯环合，已经建立了一种简单而有用的方案，可产生不同的4 H-吡啶并[1，2-a]嘧啶-4-酮。已证明使用乙二醇有助于这种缩合。该反应在无催化剂的情况下，在正常的绿色大气条件下，通过无毒，廉价，环境友好和可生物降解的溶剂进行。