The present work is aimed mainly to synthesize new fluorinated compounds and their biological significance against tested bacteria and fungus. Thus, the 4-amino-2-ethoxy-3,5,6-trifluoropyridine 4 was synthesized by the reaction of 4-amino 2,3,5,6-tetrafluoropyridine 1 with benzaldehyde 2 in EtOH to obtain the pure product as white crystals in 33% yield. The purity of this compound was estimated by TLC technique and microanalysis while its structure was supported by the usual spectroscopic methods such as UV, infrared, 1H. NMR, and gas chromatography coupled by a mass spectrometry (GC/MS). 4-amino 2,3,5,6-tetrafluoropyridine 1 coupled readily to benzaldehyde 2 when we have used THF as solvent resulting a new Schiff base (E)-N-benzylidene-2,3,5,6-tetrafluoropyridin-4-amine 3 in 48 % yield. Exploration of the anti-bacterial activity against both gram-positive and gram-negative bacteria showed that these compounds 3 and 4 compounds at a concentration of 250 µg/ml exhibited a slight activity towards Enterococcus feacium; Streptocoque B and Staphylococus aureus exhibited a mild/moderate activity for the case of Escherichia coli and Salmonella typhimurium when compared to Ampicillin. From the results obtained by the antifungal activity, it is found that this fluorinated Schiff base 3 and fluorinated ethoxypyridine 4 are more active against Candida albicans at a concentration of 250 µg/ml when compared to Nystatine.
本研究的主要目的是合成新的含
氟化合物及其对测试细菌和真菌的
生物学意义。因此,4-
氨基-2-乙氧基-3,5,6-三
氟吡啶 4 是由 4-
氨基 2,3,5,6-四
氟吡啶 1 与
苯甲醛 2 在 EtOH 中反应合成的,得到的纯品为白色晶体,产率为 33%。该化合物的纯度通过 TLC 技术和显微分析进行了估算,而其结构则通过紫外、红外、1H.NMR 和气相色谱-质谱联用仪 (GC/MS)。当我们使用
四氢呋喃作为溶剂时,4-
氨基 2,3,5,6-四
氟吡啶 1 很容易与
苯甲醛 2 发生偶联,从而产生了新的希夫碱 (E)-N-亚苄基-2,3,5,6-四
氟吡啶-4-胺 3,收率为 48%。对革兰氏阳性菌和革兰氏阴性菌的抗菌活性研究表明,与
氨苄西林相比,浓度为 250 µg/ml 的化合物 3 和化合物 4 对粪肠球菌、B 型链球菌和
金黄色葡萄球菌表现出轻微/中等的活性,而对大肠杆菌和伤寒沙门氏菌则表现出轻微/中等的活性。从抗真菌活性得出的结果发现,与 Nystatine 相比,当浓度为 250 µg/ml 时,
氟化席夫碱 3 和
氟化乙氧基
吡啶 4 对白色念珠菌的活性更高。