Abstract An efficient method for the synthesis of potentially biologically [2H]-pyrido [1,2-b]1,2,4-triazines derivatives is described via reaction of 1,6-diamino-2-oxo-4-phenyl-1,2-dihydropyridine-3,5-dicarbonitrile derivatives with oxalyl chloride in DMF in the presence of pyridine as a base. The intramolecular hydrogen bonding (IMHB) interactions have been investigated at M06-2X/6-311++G(d,p) level of theory. The eight compounds (5a-h) characterized by geometries and energies. The Natural bond orbital (NBO) and quantum theory of atoms in molecules (QTAIM) were performed to explore the nature of the hydrogen-bonding interactions in these compounds. The IMHB formed between the C O and N H groups. The theoretical calculations showed that the IMHB strength increases in the presence of electron-donor substituents. An opposite behavior was observed for electron-acceptor substituents.

中文翻译：

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吡啶三嗪-核合成和理论研究：2,3,6-trioxo-8-aryl-1,3,4,6-四氢-]2H[pyrido]1,2-b] [1,2,4[triazin] -7,9-二羰基衍生物

摘要描述了一种通过 1,6-diamino-2-oxo-4-phenyl-1 的反应合成潜在生物 [2H]-pyrido [1,2-b]1,2,4-triazines 衍生物的有效方法。 ,2-二氢吡啶-3,5-二甲腈衍生物与草酰氯在 DMF 中在吡啶作为碱的存在下。已在 M06-2X/6-311++G(d,p) 理论水平研究了分子内氢键 (IMHB) 相互作用。八种化合物 (5a-h) 以几何形状和能量为特征。进行了自然键轨道 (NBO) 和分子中原子的量子理论 (QTAIM) 以探索这些化合物中氢键相互作用的性质。IMHB 在 CO 和 NH 基团之间形成。理论计算表明，在给电子取代基的存在下，IMHB 强度增加。