去甲斑蝥素酰胺类衍生物的合成及杀虫活性

Synthesis and insecticidal activity of amides derivatives of norcantharidin

【目的】寻找新的具有高杀虫活性的斑蝥素类化合物,为新型高效、低毒、低残留农药的研发提供参考。【方法】以去甲斑蝥素为先导化合物,保留其六元环与氧桥部分,用脂肪胺或芳香胺通过酰化反应取代其结构中的酸酐部分,设计合成了20种去甲斑蝥素酰胺类衍生物,采用核磁共振、高分辨质谱及红外光谱等方法对其结构进行测定,并采用浸叶法初步测定了合成衍生物对小菜蛾3龄幼虫的杀虫活性。【结果】合成的20种化合物中,NC-1、NC-3、NC-4、NC-9、NC-10、NC-13、NC-16、NC-17、NC-18、NC-19、NC-20等11种化合物尚未见文献报道。在500mg/L质量浓度下,除NC-3、NC-11、NC-17未表现出杀虫活性外,其余17种化合物对小菜蛾均表现出一定的杀虫活性,其中化合物NC-8与NC-10的致死率达100%;进一步测定表明,在100mg/L质量浓度下,NC-8的致死率为34.59%,优于母体化合物去甲斑蝥素。【结论】当引入基团为脂肪族时,杀虫活性随着脂肪链的延长而减弱;当引入基团为芳香环时,苯环上不同取代位点引入电负性不同的取代基会对杀虫活性产生较大影响。

【Objective】 This study is trying to find new cantharidin-related compounds with highly insecticidal activity,in order to provide reference for developing the new pesticide which is highly active,less-toxic and less-persistent.【Method】 Twenty amides derivatives are synthesized with norcantharidin as the lead compound via the replacement of anhydride ring of norcantharidin with the fatty amine or aromatic amine by acylation reaction.The structures of all the newly synthesized compounds were confirmed by 1H NMR,HRMS and IR.The insecticidal activity of the 20 derivatives on the Plutella xylostella had been determined.【Result】 Among the twenty derivatives synthesized in this paper,the compounds NC-1,NC-3,NC-4,NC-9,NC-10,NC-13,NC-16,NC-17,NC-18,NC-19 and NC-20 are novel.All the compounds exhibit some insecticidal activity at concentration 500 mg/L except the NC-3,NC-11 and NC-17,among them,the morality ration of the NC-8 and NC-10 against P.xylostella are 100%.The further bioassay demonstrated the insecticidal activity of compound NC-8 with the morality ration 34.59% at concentration 100 mg/L,was higher than the corresponding parent compound norcantharidin.【Conclusion】 The insecticidal activity reduced with increasing of aliphatic substituent＇s steric hindrance and influenced by the substituents with different electronegativity on the benzene ring.