Bisbenzimidazole Derivatives as Potential Antimicrobial Agents: Design, Synthesis, Biological Evaluation and Pharmacophore Analysis
作者:Ronak Haj Ersan、Kayhan Bolelli、Serpil Gonca、Aylin Dogen、Serdar Burmaoglu、Oztekin Algul
DOI:10.1007/s11094-021-02389-x
日期:2021.5
In an attempt to design and synthesize a potent class of antimicrobials, 1,2-phenylenediamine derivatives were reacted with various aliphatic and heteroaliphatic dicarboxylic acids to generate a small library of 26 head-to-head bisbenzimidazole compounds (16 – 42) using the polyphosphoric acid method. These compounds were screened for their antibacterial activity and their antifungal activity. Compound 25 showed maximum potency against both Gram-positive and Gram-negative bacterial strains with minimum inhibitory concentration (MIC) values in the range of 7.81 – 31.25 μg/mL. In particular, it showed the maximum MIC values of 7.81 μg/mL against Gram-negative bacteria, which was four-fold more active than the standard drug ampicillin (MIC = 32.25 μg/mL). Compound 19 was found to be the most active against S. aureus with a MIC value of < 3.90 μg/mL, whereas the remaining compounds showed only low-to-moderate activity. Furthermore, all compounds exhibited low activity against all fungal strains in comparison to the standard drug fluconazole. I addition, pharmacophore hypotheses were generated to analyze structure–activity relationships between the molecular structures and antimicrobial activities on E. coli. This pharmacophore model can be useful in order to design new antimicrobial drugs. It can be suggested that the substitution of a phenyl ring at the 5/6 and 5′/6′ positions in symmetric bisbenzimidazole derivatives produces compounds with promising antimicrobial activity.
为了设计并合成一类高效的抗菌药物,我们通过多磷酸法,将1,2-苯二胺衍生物与各种脂肪族和杂脂肪族二羧酸反应,生成了一个包含26个头对头双苯并咪唑化合物(16 – 42)的小型库。这些化合物经过筛选,评估了它们的抗菌活性和抗真菌活性。化合物25对革兰氏阳性和革兰氏阴性细菌株显示出最高的活性,其最低抑制浓度(MIC)值在7.81至31.25 μg/mL范围内。特别是,它对革兰氏阴性细菌显示出最高的MIC值7.81 μg/mL,比标准药物氨苄西林(MIC = 32.25 μg/mL)高出四倍。化合物19对金黄色葡萄球菌显示出最高的活性,其MIC值小于3.90 μg/mL,而其他化合物仅显示出低至中等的活性。此外,与标准药物氟康唑相比,所有化合物对所有真菌株均显示出低活性。此外,生成了药效团假设,以分析大肠杆菌上的分子结构与抗菌活性之间的结构-活性关系。这个药效团模型对于设计新的抗菌药物可能非常有用。可以建议,在对称双苯并咪唑衍生物的5/6和5′/6′位置上取代苯环会产生具有有前景的抗菌活性的化合物。