Chemical analysis of the crude extract of bacterial strain Bacillus amyloliquefaciens ELI149, which had been previously isolated from soil, resulted in the isolation and characterization of two known macrolactin derivatives, macrolactin A (1) and 7-O-succinyl macrolactin A (2). The structures of two compounds were assigned by 1D/2D NMR techniques. The two compounds were demonstrated antifungal activity against some important phytopathogens. However, the presence of the succinyl moiety at C-7 gives to the molecule more activity being the second compound more active than the first, showing for the first time, a structure/activity relationship. The cellular damage was also studied in two important phytopathogen fungi.

中文翻译：

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来自解淀粉芽孢杆菌 ELI149 的 7-O-琥珀酰大环内酯 A 与大环内酯 A 的强抗真菌活性

对先前从土壤中分离的解淀粉芽孢杆菌 ELI149 的粗提取物进行化学分析，可以分离和表征两种已知的大环内酯衍生物，大环内酯 A (1) 和 7-O-琥珀酰大环内酯 A (2)。两种化合物的结构通过 1D/2D NMR 技术确定。这两种化合物被证明对一些重要的植物病原体具有抗真菌活性。然而，C-7 处琥珀酰基部分的存在使分子具有更高的活性，因为第二种化合物比第一种化合物活性更高，首次显示出结构/活性关系。还在两种重要的植物病原体真菌中研究了细胞损伤。