Alkyl esters and alkyl amides of 1,4-dihydro-1,2,4,5-tetrazine-3,6-dicarboxylic acid were synthesised and characterised by IR, 1H NMR, EI-MS and elemental analysis. The structure of 1,4-dihydro-1,2,4,5-tetrazine-3,6-dicarboxylic was confirmed by X-ray diffraction analysis. Some selected compounds were evaluated against P-388 and A-549 cancer cell lines, but showed poor inhibitory activities.

中文翻译：

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1,4-二氢-1,2,4,5-四嗪-3,6-二羧酸酯和酰胺的合成

合成了1,4-二氢-1,2,4,5-四嗪-3,6-二羧酸的烷基酯和烷基酰胺，并通过IR、1H NMR、EI-MS和元素分析对其进行了表征。1,4-二氢-1,2,4,5-四嗪-3,6-二羧酸的结构由X射线衍射分析证实。一些选定的化合物针对 P-388 和 A-549 癌细胞系进行了评估，但显示出较差的抑制活性。