Three new bis-condensed Schiff bases (1-3), one imidazo-pyridine (4) and twelve Schiff base metal complexes derived from 2,3-diaminopyridine (DAPY) have been synthesised. The mixed Schiff bases DAPY-ValH}SalH} (1) and DAPY-ValH}(DhbH2} (2) were obtained by equimolar reaction of the mono-condensed Schiff base of DAPY and o-vanillin (ValH), DAPY-ValH}with salicylaldehyde (SalH) and 2,3-dihydroxybenzaldehyde (DhbH2), respectively. 1:2 Molar condensation of DAPY with DhbH2 yielded the Schiff base (3), whereas reaction of the same reagents in a 1:0.8 mol ratio gave the imidazo-pyridine, 2-(2,3-dihydroxyphenyl)-1H-imidazo-( 4,5-b)pyridine (4). The Schiff bases and Schiff base metal complexes (1600 μg cm-3) were screened in vitro against three bacteria (Staphylococcus aureus, Bacillus subtilis and Escherichia coli) using the diffusion method. Some of them were found to be more active than the control cetyl trimethyl ammonium bromide.
我们合成了三个新的双缩合希夫碱(1-3)、一个
咪唑吡啶(4)和十二个源自 2,3-二
氨基吡啶(DAPY)的希夫碱
金属配合物。混合席夫碱 DAPY-ValH}SalH} (1) 和 DAPY-ValH}(DhbH2} (2) 分别是通过 DAPY 和
邻香兰素(ValH)的单缩合席夫碱、DAPY-ValH}与
水杨醛(SalH)和
2,3-二羟基苯甲醛(DhbH2)的等摩尔反应得到的。DAPY 与 DhbH2 以 1:2 摩尔比缩合生成希夫碱 (3),而相同试剂以 1:0.8 摩尔比反应生成
咪唑吡啶,即 2-(2,3-二羟基苯基)-
1H-咪唑并( 4,5-b)
吡啶 (4)。利用扩散法对希夫碱和希夫碱
金属配合物(1600 μg cm-3)对三种细菌(
金黄色葡萄球菌、枯草杆菌和大肠杆菌)进行了体外筛选。结果发现,其中一些比对照组
十六烷基三甲基溴化铵更有效。