新型2-甲基-3-呋喃甲酰胺类化合物的设计、合成及抑菌活性研究

为寻找高活性抑菌化合物,20种以杀菌剂甲呋酰胺为结构基础的新型2-甲基-3-呋喃甲酰胺类化合物经过设计并合成,它们的结构已通过氢核磁确定.接着,选取5种常见且具有代表性的植物病原真菌(水稻纹枯病菌、油菜菌核病菌、马铃薯晚疫病菌、番茄绵腐病菌、苹果轮纹病菌)作为供试菌种,采用生长速率法对所合成的目标化合物进行了抑菌活性初步筛选.结果表明:在浓度为20mg/L时,化合物1e,1f,2a,2b和2f对水稻纹枯病菌的校正抑菌率分别为88.6%、74.5%、78.5%、78.7%和73.1%,优于阳性对照甲呋酰胺(70.5%).进一步对5种化合物抑制水稻纹枯病菌有效中浓度(EC_(50))的测定,发现化合物1e的EC_(50)值为2.824mg/L,优于阳性对照杀菌剂甲呋酰胺(EC_(50)=7.691mg/L).表明化合物1e对水稻纹枯病菌抑菌活性最强,可作为先导化合物进一步结构优化.

Design, synthesis and antifungal activity of novel 2-methyl-3-furancarboxamide derivatives

Abstract: Based on the structure of the fungicide fenfuram, twenty novel 2-methyl-3-furancarboxamide derivatives were designed, synthesized characterized by 1H NMR. Their in vitro antifungal activities were evaluated against five normal phytopathogenic fungi Rhizoctonia solani, Sclerotinia sclerotiorum, Phytophthora infestans, Pythium aphanidermatum, Physalospora piricola by mycelial growth inhibition method. Compounds 1e, 1f, 2a, 2b and 2f exhibited stronger antifungal effect on R. solani with inhibition of 88.6 %, 74.5 %, 78.5 %, 78.7 % and 73.1 %, respectively, superior to commercial fungicides fenfuram (70.5 %). The EC50 values of the five tested compounds against R. solani showed that compound 1e exhibited the most potent inhibition with an EC50 value of 2.824 mg/L which lower than fenfuram (EC50 = 7.691 mg/L). As a result, compound 1e could be the lead compound for the following research.