ABSTRACT A series of new bioactive cinnoline/ Isoxazole hybrid heterocyclics (7a-p) have been designed and synthesized from cinnoline by applying the regioselective nitrile oxide[1,3]-dipolar cycloadditions. All the synthesised compoundswere screened for their in vitro antibacterial activity. The results of screening revealed that compounds 7f, 7g, 7k, 7l, and 7o are potent antibacterial agents against the Gram- positive bacterial species Bacillus subtilis and Staphylococcus aureus as well as Gram- negative bacterial species Pseudomonas aeruginosa and Escherichia coli. When compared with the standard drug norfloxacin, compound 7k showed more potent antibacterial activity against the all Gram-positive and Gram-negative strains of bacteria. To understand the binding interactions of the most derivatives 7f, 7g, 7k, 7l and 7k molecular docking studies were performed with elastase of Pseudomonas aeruginosa (PDB: 1U4G ). These docking results revealed that this class of compounds have potential antibacterial activity.

中文翻译：

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新型肉桂-异恶唑衍生物的合成及抗菌活性

摘要 通过应用区域选择性氧化腈[1,3]-偶极环加成反应，从肉啉中设计并合成了一系列新的生物活性肉桂/异恶唑杂环化合物（7a-p）。筛选所有合成化合物的体外抗菌活性。筛选结果表明，化合物 7f、7g、7k、7l 和 7o 是针对革兰氏阳性菌枯草芽孢杆菌和金黄色葡萄球菌以及革兰氏阴性菌铜绿假单胞菌和大肠杆菌的强效抗菌剂。与标准药物诺氟沙星相比，化合物 7k 对所有革兰氏阳性和革兰氏阴性细菌菌株显示出更有效的抗菌活性。要了解大多数衍生物 7f、7g、7k 的结合相互作用，使用铜绿假单胞菌的弹性蛋白酶 (PDB: 1U4G) 进行了 7l 和 7k 分子对接研究。这些对接结果表明该类化合物具有潜在的抗菌活性。