S-(2-吡啶基-N-氧化物)-N-取代或-N,N′-双取代异硫脲氢溴酸盐的合成及抗菌活性

SYNTHESIS OF S-(-PYRIDYL -N-OXIDE)N-SUBSTITUTED OR -N,N'-DISUBSTITUTED ISOTHIOUREA HYDROBROMIDES ANDTHEIRANTIM ICKOBIALACTIVITY

摘要: 为寻找高效广谱的防霉抗菌剂,设计合成了19个S-(2-吡啶基-N-氧化物)-N,N'-单或双取代异硫脲氢溴酸盐(lb～1,lla～f,IIla～b),并与目前认为最好的防霉抗菌剂MI861(la)比较,探索构效关系。初步抗菌试验表明:上述化合物对常见的三种霉菌(黑曲霉,桔青霉,木霉),二种细菌(大肠杆菌,枯草杆菌)均有不同程度的抑制作用,其中IIla的抗菌效果超过MI861,其最低抑制浓度(MIC)在0.5～5ppm之间,Ic,If和Ik的抗菌效果与Ml861相当。

Abstract: To obtain more potent and wide-spectrum antimicrobial agent,twenty S-(2-pyridyl-N-oxide)-N一substituted or -N’-disubstituted isothiourea hydrobromides were synthesized, nineteen of which were new。The minimum inhibitory concentrations(MICs )of these compounds against Aspergillus niger,Penicillium citrinum, Trichoderma sp.,Escherichia coli and Bacillus subtilis eere tested with the method of liquid shake culture and the antimicrobial activities were observed.The best compound was found to beS-(2-pyridyl-N-oxide)-N,N’-1,3- ethylene isothiourea hydrobromide (IIIa),and its antimicrobial　activity(MIC0.5～5ppm)was shown to be superior to that of MI861(Ia,lead compound).The　antimicrobial activities of the nine target compounds were found to be superior to that of Ia against E.coli and B.subtilis.Further research showed that IIIa is a wide-spectrum anti-microbial agent.