8-Hydroxyquinoline derivatives are known for their extensive applications in the field of analytical chemistry and separation techniques; their complexes with transition metals also exhibit antibacterial and antifungal activity. In the present study, we synthesized a new series of pyranoquinoline derivatives and evaluated their antibacterial activities. The structures of the synthesized compounds were characterized by Fourier transform infrared (FT-IR), hydrogen-1 nuclear magnetic resonance, carbon-13 nuclear magnetic resonance, and elemental analysis. All the prepared compounds were evaluated in vitro as antimicrobial agents against Gram-positive and Gram-negative bacterial strains (Escherichia coli (ATCC35218), Staphylococcus aureus (ATCC29213), Vibrio parahaemolyticus (ATCC17802), and Pseudomonas aeruginosa (ATCC27853)). The screening test was determined by using the standard protocol of disc diffusion method (DDM). We have synthesized new pyranic compounds bearing an 8-hydroxyquinoline moiety on their structure. The preliminary screening results showed that all the tested compounds have a remarkable inhibitory effect on the growth of the majority of the tested bacterial strains compared to the standard antibiotic (penicillin G), and the chlorinated compound (Q1) is more active against Gram-positive bacteria than Gram-negative bacteria such as the Staphylococcus aureus strain which is the most sensitive. Gram-positive bacteria are responsible for a wide range of infectious diseases, and rising resistance in this group is causing increasing concern. Thus, this study develops novel heterocyclic compound derivatives of 8-hydroxyquinoline that have demonstrated good antibacterial activity against Gram-positive bacteria.

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基于 8-羟基喹啉的新型吡喃衍生物的合成、表征和体外抗菌研究

8-羟基喹啉衍生物以其在分析化学和分离技术领域的广泛应用而闻名；它们与过渡金属的配合物也表现出抗菌和抗真菌活性。在本研究中，我们合成了一系列新的吡喃喹啉衍生物并评估了它们的抗菌活性。合成化合物的结构通过傅里叶变换红外(FT-IR)、氢一核磁共振、碳13核磁共振和元素分析表征。所有制备的化合物都在体外评估作为抗革兰氏阳性和革兰氏阴性细菌菌株（大肠杆菌（ATCC35218）、金黄色葡萄球菌（ATCC29213）、副溶血性弧菌（ATCC17802）和铜绿假单胞菌（ATCC27853））的抗菌剂。筛选试验通过使用圆盘扩散法(DDM)的标准方案确定。我们合成了在其结构上带有 8-羟基喹啉部分的新型吡喃化合物。初步筛选结果表明，与标准抗生素（青霉素G）相比，所有受试化合物对大多数受试菌株的生长都有显着的抑制作用，氯化化合物（Q1）对革兰氏阳性菌的活性更强细菌比革兰氏阴性菌如金黄色葡萄球菌菌株最敏感。革兰氏阳性菌是多种传染病的罪魁祸首，这一群体中不断上升的耐药性引起了越来越多的关注。因此，