Efficient, One-Pot Synthesis of Triazolothiadiazinyl-pyrazolone and Pyrazolyl-triazolothiadiazine Derivatives via Multicomponent Reaction

A one-pot, multicomponent reaction of 3-(2-bromo acetyl)coumarins, 4-amino-5-hydrazino-4H-[1,2,4]triazole-3-thiol, and different derivatives of ethyl 2-(2-(aryl)hydrazono)-3-oxobutanoates provide an efficient and direct method for the synthesis of 4-(arylydrazono)-3-methyl-1-(6-(coumarin-3-yl)-7H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-3-yl)-1H-pyrazol-5(4H)-ones (4a–h). A similar methodology was also developed for the synthesis of pyrazolyl-triazolothiadiazines (9a–f) using acetyl acetone, 4-amino-5-hydrazino-4H-[1,2,4]triazole-3-thiol, and different derivatives of phenacylbromide. The resulting products were characterized by analytical and spectral data.

以3-(2-溴乙酰基)香豆素、4-氨基-5-肼基-4H-[1,2,4]三唑-3-硫醇及2-(2-(芳基)腙基)-3-氧代丁酸乙酯的不同衍生物为原料，通过一锅法多组分反应，可高效直接合成4-(芳基腙基)-3-甲基-1-(6-(香豆素-3-基)-7H-[1,2,4]三唑并[3,4-b][1,3,4]噻二嗪-3-基)-1H-吡唑-5(4H)-酮（4a–h）。采用乙酰丙酮、4-氨基-5-肼基-4H-[1,2,4]三唑-3-硫醇与不同取代的α-溴代苯乙酮衍生物为原料，亦可建立类似的合成策略，制备得到吡唑基三唑并噻二嗪类化合物（9a–f）。所得产物均通过分析测试与光谱数据完成结构表征。