2-取代硫醚(砜)-5-(4-硝基或4-甲氧苯基)-1,3,4-噻二唑类化合物的合成及抑菌活性

Synthesis and Antifungal Activity of 2-Substituted Sulfinyl (Sulfonyl)-5-(4-nitro or 4-methoxyphenyl)-1,3,4-thiadiazole Derivatives

以4-硝基苯甲酸和4-甲氧基苯甲酸为起始原料,经酯化、酰肼化、成钾盐、闭环、硫醚化合成7个新化合物5.在乙醇中钼酸铵催化过氧化氢氧化合成了10个2-取代磺酰-5-(4-硝基或4-甲氧苯基)-1,3,4-噻二唑砜化合物6.所有化合物结构经过1HNMR,13CNMR,IR和元素分析确证.初步生物活性试验结果表明,在500μg·mL-1浓度下化合物5d对小麦赤霉病菌、辣椒枯萎菌、苹果腐烂菌的抑制率分别为99.0%,100.0%,100.0%;化合物6j在50μg·mL-1的浓度下对小麦赤霉病菌、辣椒枯萎菌、苹果腐烂菌的也有较好的抑制活性,其抑制率分别为47.7%,46.4%和50.6%.

Starting from p-nitrobenzoic acid and p-methoxybenzoic acid,seven new 2-sub-stitutedthio-5-（4-nitro or 4-methoxyphenyl）-1,3,4-thiadiazole compounds 5 were synthesized in five steps including esterification,hydrazidation,salt formation,cyclization and thioetherification. Treatment of 5 with H2O2 catalyzed by ammonium molybdate in ethanol afforded the ten 2-substituted sulfonyl-5-（4-nitro or 4-methoxyphenyl）-1,3,4-thiadiazole 6 with good yields. The structures of the new compounds synthesized were confirmed by 1H NMR,13C NMR,IR spectra and elemental analysis. The preliminary bioassay showed that compound 5d had good antifungal activity against Fusarium graminearum,Fusarium oxysporum and Cytospora mandshurica with the rate of 99.0%,100.0% and 100.0% at the concentration of 500 μg·mL-1,and compound 6j possessed high inhibitory effect with rate of 47.7%,46.4% and 50.6% at the concentration of 50 μg·mL-1.