Abstract:
Carbamate is a key structural motif in the development of fungicidal compounds, which is still promising and robust in the discovery of green pesticides. Herein, we report the synthesis and evaluation of the fungicidal activity of 35 carbamate derivatives, among which 19 compounds were synthesized in our previous report. These derivatives were synthesized from aromatic amides in a single step, which was a green oxidation process for Hofmann rearrangement using oxone, KCl and NaOH. Their chemical structures were characterized by 1H NMR, 13C NMR and high-resolution mass spectrometry. Their antifungal activity was tested against seven plant fungal pathogens. Many of the compounds exhibited good antifungal activity in vitro (inhibitory rate > 60% at 50 μg/mL). Compound 1ag exhibited excellent broad-spectrum antifungal activities with inhibition rates close to or higher than 70% at 50 μg/mL. Notably, compound 1af demonstrated the most potent inhibition against F. graminearum, with an EC50 value of 12.50 μg/mL, while compound 1z was the most promising candidate fungicide against F. oxysporum (EC50 = 16.65 μg/mL). The structure-activity relationships are also discussed in this paper. These results suggest that the N-aryl carbamate derivatives secured by our green protocol warrant further investigation as potential lead compounds for novel antifungal agents.
摘要:
氨基甲酸酯是杀真菌化合物开发中的关键结构基序,在发现绿色农药方面仍然很有希望和强大。在这里,我们报道了35种氨基甲酸酯衍生物的合成和杀菌活性的评价,其中19个化合物是在我们之前的报告中合成的。这些衍生物由芳族酰胺在一个单一的步骤中合成,这是使用oxone进行霍夫曼重排的绿色氧化过程,KCl和NaOH。其化学结构经1HNMR表征,13CNMR和高分辨率质谱。测试了它们对7种植物真菌病原体的抗真菌活性。许多化合物在体外表现出良好的抗真菌活性(在50μg/mL时的抑制率>60%)。化合物1ag表现出优异的广谱抗真菌活性,在50μg/mL时的抑制率接近或高于70%。值得注意的是,化合物1af对F.graminearum表现出最有效的抑制作用,EC50值为12.50μg/mL,而化合物1z是最有希望的抗尖孢酵母的候选杀真菌剂(EC50=16.65μg/mL)。本文还讨论了结构-活动关系。这些结果表明,通过我们的绿色方案获得的N-芳基氨基甲酸酯衍生物值得进一步研究,作为新型抗真菌剂的潜在先导化合物。