3-取代-6-吡唑基-1,2,4-三唑并[3,4-b]-1,3,4-噻二唑类衍生物的合成及生物活性

将5-取代吡唑-3-甲酸乙酯1位甲基化，经水解反应得到3种中间体1-甲基-5-取代1H-吡唑-3-甲酸（2a~2c）；以不同取代的羧酸为原料经一系列反应合成6种中间体3-取代4-氨基-5-巯基-1,2,4-均三唑（3a~3f）；将中间体（2a~2c）和（3a~3f）在三氯氧磷条件下反应，合成出18种1,2,4-三唑并3,4-b]-1,3,4-噻二唑类化合物(4a~4r)，均未见文献报道。 通过IR、1H NMR、13C NMR和元素分析表征了化合物结构。 初步的生物活性测试结果显示,所合成的化合物均表现出不同程度的生长素活性和抑菌活性。 并选取抑菌活性较好的两个化合物进行抗菌药物最低抑菌浓度(MIC)的测定。

Synthesis and Biological Activities of 3-Substituted-6-pyrazole-1,2,4-triazolo[3,4-b]-1,3,4-thiadiazoles

The three kinds of 1-methyl-5-substituted-pyrazole-3-carboxylic acid(2a~2c) were obtained by 5-substituted-1H-pyrazole-3-ethyl formate based on methylation and hydrolysis of the ester. Then the six kinds of 3-substituted-4-amino-5-mercapto-1,2,4-triazale(3a~3f) were obtained using the substituted carboxylic acid by a series of reaction; Finally, eighteen novel 1,2,4-triazolo3,4-b]-1,3,4-thiadiazoles compounds(4a~4r) were synthesized by phosphorus chloride treatment of compounds(2a~2c, 3a~3f). The structures of all new compounds were characterized by IR, 1H NMR, 13C NMR and elemental analyses. The preliminary test shows that all the compounds(4a~4r) display auxin activity and fungicidal activity to some extent. Among these compounds, minimum inhibitory concentrations(MIC) were measured for the superior two by antimicrobial.