In this letter, we reported synthesis of 2,4-Diacetylphloroglucinol (DAPG) derivatives as a new class of anti fungal agents. A series of DAPG ester analogues with diverse length of acyl substitution on aromatic hydroxyls were synthesized and characterized by H, C NMR and ESI-MS. Their antifungal activities were evaluated against six important plant fungal pathogens using mycelial growth inhibitory rate assay. A clear structure-activity relationship (SAR) study of the diacylphloroglucinols was investigated. Compounds , -, , and exhibited broad-spectrum anti fungal activity, in addition, the anti fungal activity was correlated with the lipid-water partition coefficient of the compounds (log ), these active analogues have log between − 0.53 and 0.19. Particularly compound (log 0.19) was found active to with IC value of 1.26 g/mL; compound (log − 0.51) was identified the most active one against (IC 1.52 g/mL). The results suggest that compound and might be promising candidates in the development of new pesticides.

中文翻译：

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2,4-二乙酰间苯三酚类似物的合成及其抗真菌活性

在这封信中，我们报道了 2,4-二乙酰基间苯三酚 (DAPG) 衍生物作为一类新型抗真菌剂的合成。合成了一系列芳香羟基上具有不同长度酰基取代的 DAPG 酯类似物，并通过 1H、13C NMR 和 ESI-MS 进行了表征。使用菌丝生长抑制率测定评估了它们对六种重要植物真菌病原体的抗真菌活性。对二酰基间苯三酚进行了清晰的构效关系 (SAR) 研究。化合物 、 - 、 和 表现出广谱抗真菌活性，此外，抗真菌活性与化合物的脂水分配系数（log ）相关，这些活性类似物的 log 在 - 0.53 至 0.19 之间。特别是化合物 (log 0.19) 具有活性，IC 值为 1.26 g/mL；化合物 (log − 0.51) 被确定为最具活性的化合物 (IC 1.52 g/mL)。结果表明，该化合物可能是开发新农药的有希望的候选者。