Synthesis, Characterization, Antibacterial and Free Radical Scavenging Activities of Some New 1,2,4-triazole Schiff Bases and Mannich Bases
作者:Kooi-Mow Sim、Siew-Theng Loo、Kah-Cheng Teo
DOI:10.2174/157017861108140613160411
日期:2014.6
The synthesis of a series of 1,2,4-triazole Schiff bases and Mannich bases incorporating an indole moiety is
described. The triazole Schiff bases were synthesized from 4-amino-3-mercapto-5-[(1H-indol-3-yl)methyl]-1,2,4-triazole
on treatment with a series of arylaldehyde in presence of (+)-tartaric acid as an acidic catalyst. The triazole Schiff bases
are further condensed with piperidine and formaldehyde to yield the corresponding series of Mannich bases. The structures
of Schiff bases and Mannich bases were established by IR, NMR and mass spectral data. All the synthesized compounds
were screened for their antibacterial and free radical scavenging activities. Schiff base 2d comprising of dichloro
substitution exhibited promising antibacterial activity against Bacillus subtilis spizizenni, Bacillus cereus and Staphylococcus
aureus at MIC 7.81 μg/ml. Mannich bases demonstrated weak free radical scavenging activity when compared to
their Schiff base counterparts.
本文描述了一系列含有吲哚结构的1,2,4-噻唑施夫碱和曼尼赫碱的合成。噻唑施夫碱是通过将4-氨基-3-巯基-5-[(1H-吲哚-3-基)甲基]-1,2,4-噻唑与一系列芳醛在(+)-酒石酸作为酸性催化剂的作用下合成的。噻唑施夫碱进一步与哌啶和甲醛缩合,得到相应的曼尼赫碱。通过红外光谱、核磁共振及质谱数据确定了施夫碱和曼尼赫碱的结构。所有合成的化合物均经过抗菌和清除自由基活性的筛选。含有二氯取代基的施夫碱2d对枯草芽孢杆菌(Bacillus subtilis spizizenni)、蜡样芽孢杆菌(Bacillus cereus)和金黄色葡萄球菌(Staphylococcus aureus)在最低抑菌浓度为7.81 μg/ml时表现出良好的抗菌活性。与其施夫碱对应物相比,曼尼赫碱显示出较弱的清除自由基活性。