In this study, we reported the synthesis and biological characterization of a novel series of furan-carboxamide derivatives that were potent inhibitors of the influenza A H5N1 virus. The systematic structure–activity relationship (SAR) studies demonstrated that the 2,5-dimethyl-substituted heterocyclic moiety (furan or thiophene) had significant influence on the anti-influenza activity. In particular, 2,5-dimethyl-N-(2-((4-nitrobenzyl)thio)ethyl)-furan-3-carboxamide 1a showed the best activity against the H5N1 virus with an EC₅₀ value of 1.25 μM. For the first time, the simple scaffold furan-carboxamide derivatives were identified as novel inhibitors of lethal H5N1 influenza A virus.

中文翻译：

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呋喃甲酰胺衍生物可作为致命的H5N1甲型流感病毒的新型抑制剂†

在这项研究中，我们报道了一系列新型的呋喃甲酰胺衍生物的合成和生物学特性，这些衍生物是甲型H5N1流感病毒的有效抑制剂。系统的结构-活性关系（SAR）研究表明，2,5-二甲基取代的杂环部分（呋喃或噻吩）对抗流感活性具有重要影响。特别地，2，5-二甲基-N-（2-（（（4-硝基苄基）硫代）乙基）-呋喃-3-羧酰胺1a显示出对H5N1病毒的最佳活性，其EC ₅₀值为1.25μM。首次将简单的支架呋喃-羧酰胺衍生物鉴定为致命的H5N1甲型流感病毒的新型抑制剂。