3-Hydroxy-2-oxindole motif constitutes a core structure in numerous natural products and imparts notable biological activities. Here, we describe the design and synthesis of four series of novel 3-substituted-3-hydroxy-2-oxindole derivatives containing sulfonamide moiety along with their antiviral activities against potato virus Y (PVY). Compound 10b displayed optimal antiviral activity and superior anti-PVY activity compared with the lead compound and commercial Ningnanmycin in terms of curative and protective effects. Additionally, 10b considerably inhibited PVY systemic infection in Nicotiana benthamiana. Physiological and biochemical analyses revealed that the activities of the four crucial defense-related enzymes increased in the tobacco plant following treatment with 10b. RNA-sequencing analysis revealed that 10b substantially induced the upregulation of 38 differentially expressed genes, which were enriched in the photosynthesis pathway. These findings suggest that 10b is a promising antiviral agrochemical that can effectively control PVY infection and trigger plant host immunity to develop virus resistance. This study provides novel molecular entities and ideas for developing new pesticides.

中文翻译：

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含有磺酰胺基序的 3-羟基-2-羟吲哚衍生物：合成、抗病毒活性和作用方式


3-羟基-2-羟吲哚基序构成了许多天然产物的核心结构，并赋予显着的生物活性。在这里，我们描述了四个系列的新型含磺酰胺部分的3-取代-3-羟基-2-羟吲哚衍生物的设计和合成及其对马铃薯Y病毒（PVY）的抗病毒活性。与先导化合物和市售宁南霉素相比，化合物10b在治疗和保护作用方面表现出最佳的抗病毒活性和优异的抗PVY活性。此外， 10b显着抑制本塞姆氏烟草中的 PVY 全身感染。生理和生化分析表明，经过10b处理后，烟草植物中四种重要的防御相关酶的活性有所增加。 RNA测序分析显示， 10b显着诱导了38个差异表达基因的上调，这些基因在光合作用途径中富集。这些发现表明10b是一种很有前途的抗病毒农用化学品，可以有效控制PVY感染并触发植物宿主免疫以产生病毒抗性。这项研究为开发新农药提供了新的分子实体和思路。