苯并咪唑类化合物的合成及辐射增敏作用

为了寻找低毒和有效的辐射增敏剂,合成了苯并咪唑类化合物2-硝基苯并咪唑-1-甲酸乙酯,2-羟基苯并咪唑-1-甲酸乙酯及1-取代2-(3’-吡啶基)-5(6)-硝基苯并咪唑类化合物,并对小鼠Ehrlich腹水癌细胞进行了辐射增敏实验,初步结果证明所试化合物有不同程度的辐射增敏效果。

SYNTHESIS AND RADIOSENSITIZING ACTIVITY OF BENZIMIDAZOLES

In search for effective radiosensitizer with low neurotoxicity, benzimidazole compounds were synthesized. Reaction of 2-nitrobenzimidazole with ethyl chloroformate yielded ethyl alpha-(2-nitrobenzimidazolyl-1)-formate(1) or ethyl alpha-(2-hydroxybenzimidazolyl-1)-formate(2), depending upon the solvents used. Reaction of 2-nitrobenzimidazole with 1,2-epoxy-3-chloropropane gave a cyclized compound which was confirmed to be benzimidazo(1,2b)-5'-chloromethyl-oxazolidine(3). In attempt to increase hydrophilicity, 1-substituted 2(3'-pyridyl)-5-nitrobenzimidazoles were prepared by reaction of 2-(3'-pyridyl)-5(6)-nitrobenzimidazole(4) with alkyl epoxides or ethyl chloroacetate. Some of the compounds synthesized were tested for radiosensitizing activity in Ehrlich ascites carcinoma-bearing mice. Preliminary results showed that some compounds have radiosensitizing activity. The radiosensitizing enhancement ratio (SER) of compounds 3, 5 and 6 were found to be 1.50, 1.52 and 1.65 respectively.