Twenty-one novel luotonin derivatives were synthesized from 2-aminobenzamide in excellent yields. The prepared compounds, when tested against 8 strains of bacteria and many plant pathogen fungi showed diverse and promising antimicrobial activities. Notably, compounds a5, a9, b4, and b5 demonstrated good activities and might be potential lead compounds for further development as antifungal agents. The relationship between structure and biological activity is also discussed.

中文翻译：

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褪黑素衍生物的合成及抗菌性能

由2-氨基苯甲酰胺以优异的产率合成了二十一种新型的褪黑素衍生物。当针对8个细菌菌株和许多植物病原真菌进行测试时，所制备的化合物显示出多种多样且有希望的抗菌活性。值得注意的是，化合物a5，a9，b4和b5表现出良好的活性，可能作为抗真菌剂进一步发展的潜在先导化合物。还讨论了结构与生物活性之间的关系。