Abstract

Herein, new four-component domino reactions are described and utilized to synthesize spiro[indoline-3,4’-pyrazolo[3,4-b]pyridine derivatives via one-pot reaction. Different hydrazine derivatives such as hydrazine hydrate, methyl hydrazine, and phenylhydrazine were allowed to react with active methylene precursors (CH₂CN) as malononitrile, ethyl cyanoacetate, isatin, and 1,3-dicarbonyl compounds in the presence of (+)-camphor-10-sulfonic acid (CSA) as the acid catalyst under microwave condition using water as the solvent. Two and three fused heterocyclic rings were obtained in a single synthetic operation with a facile work-up and less waste generation due to the absence of extraction and purification steps. Structural features of the obtained compounds were confirmed by utilizing elemental analyses, mass spectrometry, ¹H-NMR, and ¹³C-NMR microanalyses. Insecticidal assessments for some of the synthesized pyrazole derivatives against the cotton leafworm Spodoptera littoralis were conducted. In addition, fungicidal activities against Rhizoctonia solani and Fusarium solani soil-borne fungi were also performed. The tested compounds showed poor insecticidal activity compared with the standard insecticide chlorpyrifos ethyl. Meanwhile, they showed remarkable fungicidal activity against tested pathogens. Analysis of the fungicidal study indicated that R. solani fungus was found to be more sensitive to the tested compounds than F. solani fungus. Some pyrazole derivatives particularly possessed close or even higher fungicidal activities than the standard fungicide Pencycuron (Monceren 25%WP). The density functional theory was then applied to explore the structural and electronic characteristics of these materials.

摘要

本文描述了新的四组分多米诺骨牌反应，并利用一锅法合成螺[indoline-3,4'-吡唑并[3,4-b]吡啶衍生物。允许不同的肼衍生物，如水合肼、甲基肼和苯肼与活性亚甲基前体（CH ₂CN) 作为丙二腈、氰基乙酸乙酯、靛红和 1,3-二羰基化合物，在 (+)-樟脑-10-磺酸 (CSA) 作为酸催化剂的情况下，在微波条件下使用水作为溶剂。由于没有提取和纯化步骤，在一次合成操作中获得了两个和三个稠合杂环，具有简单的后处理和更少的废物产生。利用元素分析、质谱、¹ H-NMR 和¹³ C-NMR 微量分析证实了所得化合物的结构特征。对一些合成的吡唑衍生物对棉叶虫Spodoptera littoralis进行了杀虫评估。此外，对立枯丝核菌的杀菌活性和Fusarium solani土传真菌也进行了研究。与标准杀虫剂毒死蜱相比，测试的化合物显示出较差的杀虫活性。同时，它们对测试的病原体表现出显着的杀菌活性。对杀菌研究的分析表明，R. solani真菌被发现对测试化合物比F. solani真菌更敏感。一些吡唑衍生物特别具有比标准杀真菌剂 Pencycuron (Monceren 25%WP) 更接近甚至更高的杀真菌活性。然后应用密度泛函理论来探索这些材料的结构和电子特性。