Abstract:
The development of novel natural product-derived nano-pesticide systems with loading capacity and sustained releasing performance of bioactive compounds is considered an effective and promising plant protection strategy. In this work, 25 L-carvone-based thiazolinone-hydrazone compounds 4a~4y were synthesized by the multi-step modification of L-carvone and structurally confirmed. Compound 4h was found to show favorable and broad-spectrum antifungal activity through the in vitro antifungal activity evaluation of compounds 4a~4y against eight phytopathogenic fungi. Thus, it could serve as a leading compound for new antifungal agents in agriculture. Moreover, the L-carvone-based nanochitosan carrier 7 bearing the 1,3,4-thiadiazole-amide group was rationally designed for the loading and sustained releasing applications of compound 4h, synthesized, and characterized. It was proven that carrier 7 had good thermal stability below 200 °C, dispersed well in the aqueous phase to form numerous nanoparticles with a size of~20 nm, and exhibited an unconsolidated and multi-aperture micro-structure. Finally, L-carvone-based thiazolinone-hydrazone/nanochitosan complexes were fabricated and investigated for their sustained releasing behaviors. Among them, complex 7/4h-2 with a well-distributed, compact, and columnar micro-structure displayed the highest encapsulation efficiency and desirable sustained releasing property for compound 4h and thus showed great potential as an antifungal nano-pesticide for further studies.
摘要:
开发具有生物活性化合物的负载能力和持续释放性能的新型天然产物衍生的纳米农药系统被认为是一种有效且有前途的植物保护策略。在这项工作中,通过L-香芹酮的多步修饰合成了25个基于L-香芹酮的噻唑啉酮-腙化合物4a〜4y,并进行了结构证实。通过化合物4a~4y对8种植物病原真菌的体外抗真菌活性评价,发现化合物4h具有良好的广谱抗真菌活性。因此,它可以作为农业新型抗真菌药物的主要化合物。此外,合理设计了带有1,3,4-噻二唑-酰胺基团的基于L-香芹酮的纳米壳聚糖载体7,用于化合物4h的负载和缓释应用,合成,和特点。证明载体7在200°C以下具有良好的热稳定性,很好地分散在水相中,形成许多尺寸约为20nm的纳米颗粒,并表现出松散和多孔径的微观结构。最后,制备了基于L-香芹酮的噻唑啉酮-腙/纳米壳聚糖复合物,并研究了其缓释行为。其中,复杂的7/4h-2具有良好的分布,紧凑型,柱状微结构在化合物4h内表现出最高的包封效率和理想的缓释性能,因此显示出作为抗真菌纳米农药的巨大潜力。