A Facile Synthesis of Aryl-Substituted Hydrazono-Pyrazolyl[1,2,4]triazolo[3,4-<i>b</i>][1,3,4][thiadiazol]-coumarin Derivatives
作者:Archi Sharma、Gudala Satish、Santhosh Penta
DOI:10.1002/jhet.2362
日期:2016.7
inimitable and therapeutic coumarin‐substituted fused[1,2,4]triazolo‐[3,4‐b][1,3,4]thiadizole derivatives were synthesized by the cyclocondensation reaction of 2‐oxo‐2H‐chromene‐3‐carboxylic acid (1) and 4‐amino‐5‐hydrazinyl‐4H‐[1,2,4]‐triazole‐3‐thiol (2) by using phosphorous oxychloride as a cyclizing agent. This cyclized intermediate 3‐(3‐hydrazino‐[1,2,4]triazolo[3,4‐b][1,3,4]thiadiazol‐6‐yl)‐chromen‐2‐one
通过2-氧代-2- H 2-色烯-3的环缩合反应合成了一些不可替代的治疗性香豆素取代的稠合[1,2,4]三唑-[3,4- b ] [1,3,4]噻二唑衍生物。羧酸(1)和4-氨基-5-肼基-4- H- [1,2,4]-三唑-3-硫醇(2),使用三氯氧磷作为环化剂。该环化的中间体3-(3-肼基-[1,2,4]三唑[3,4- b ] [1,3,4]噻二唑-6-基)-铬-2--1(3)之后缩合在NaOAc / MeOH中,在回流条件下,各种2-(2-芳基肼基)-3-氧代丁酸乙酯(4)提供相应的新系列芳基取代的肼基-吡唑基-[1,2,4]三唑并[3,4-b ] [1,3,4] [噻二唑]-香豆素衍生物(5),具有良好的收率。在元素分析,IR,1 H NMR和质谱研究的基础上,建立了新合成化合物的结构。