In this research, synthesis, antimicrobial and antioxidant activities of a series of catecholthioethers having benzoxazole and tetrazole moieties are described. Antimicrobial activity was evaluated by minimum inhibitory concentration (MIC) assay. The synthesized compounds were tested in vitro against three Gram-positive bacteria including Staphylococcus aureus (clinical isolated), Staphylococcus aureus ATCC 25922, Enterococcus faecium (clinical isolated), and two Gram-negative bacteria including Klebsiella pneumoniae (clinical isolated) and Pseudomonas aeruginosa 27853 and the yeast Candida albicans in comparison with control drugs. Microbiological results indicated that the synthesized compounds possessed a broad spectrum of activity against the tested microorganisms at MIC values between 4—256 μg/ml. This shows compounds having tetrazole moiety were the most active against Gram-negative strains, whereas compounds having benzoxazole moiety were more active against Gram-positive ones. Also both of them showed significant antifungal activity against Candida albicans and had lower activity than the compared control drugs (Sulfamethoxazole and Fluconazole). The antioxidant activity was assessed using two methods, including, 1,1-biphenyl-2-picrylhydrazyl (DPPH) radical scavenging, and reducing power assays. Some of the catecholthioether derivatives showed antioxidant activity more than Trolox and butylated hydroxyanisole (BHA) as reference antioxidants.
在这项研究中,描述了一系列具有苯并
噁唑和
四唑基团的
儿茶酚硫醚的合成、抗微
生物和抗氧化活性。抗微
生物活性通过最低抑菌浓度(MIC)测定进行评估。合成的化合物在体外测试了三种革兰氏阳性细菌,包括
金黄色葡萄球菌(临床分离株)、
金黄色葡萄球菌A
TCC 25922、肠球菌(临床分离株),以及两种革兰氏阴性细菌,包括肺炎克雷伯菌(临床分离株)和
铜绿假单胞菌27853,以及酵母菌白色念珠菌,并与对照药物进行比较。微
生物学结果表明,合成的化合物在4—256 μg/ml的MIC值范围内对测试微
生物具有广谱活性。这表明具有
四唑基团的化合物对革兰氏阴性菌株的活性最强,而具有苯并
噁唑基团的化合物对革兰氏阳性菌株的活性更强。此外,两者对白色念珠菌也表现出显著的抗真菌活性,但活性低于比较的对照药物(
磺胺甲
噁唑和
氟康唑)。抗氧化活性通过两种方法评估,包括1,1
-二苯基-2-
吡啶肼(
DPPH)自由基清除和还原力测定。一些
儿茶酚硫醚衍
生物的抗氧化活性超过了作为参考
抗氧化剂的特罗克斯和丁基羟基
苯甲醚(
BHA)。