Synthesis of 3-Substituted Bicyclic Imidazo[1,2-<i>d</i>][1,2,4]thiadiazoles and Tricyclic Benzo[4,5]imidazo[1,2-<i>d</i>][1,2,4]thiadiazoles
作者:Regis Leung-Toung、Tim F. Tam、Yanqing Zhao、Craig D. Simpson、Wanren Li、Denis Desilets、Khashayar Karimian
DOI:10.1021/jo0507486
日期:2005.8.1
cyanide) under mild conditions is described. For example, the tricyclic 3-bromo [1,2,4]THD derivative (7a) underwent SNAr substitution with a variety of nucleophiles, which included amines, malonate esters and alcohols. Likewise, the bicyclic 3-p-tosyl [1,2,4]THD (10b) was employed as a template in reaction with diamines, and the resulting substituted diamines (e.g., 12a or 12e) were further selectively
通过前体[1,2,4] thiadiazol-3-(2 H)one衍生物的交换反应(可能为有用的稠合环[1,2,4]噻二唑支架(例如7a和10b)的通用合成路线)(例如,6和9)与适当取代的腈类(例如溴化氰或p温和的条件下对甲苯磺酰氰化物)进行说明。例如,所述三环3-溴- [1,2,4] THD衍生物(图7a)行小号Ñ氩置换与各种亲核试剂,其中包括胺,丙二酸酯和醇。同样,双环3-对甲苯磺酰基[1,2,4] THD(10b)用作与二胺反应的模板,并且将所得的取代的二胺(例如12a或12e)以线性方式进一步选择性地在N1和/或N2位置衍生化。如方案6所示,获得了3-甲基双环[1,2,4] THD(21)的X射线晶体结构,并确认了通过保护-烷基化-脱保护方案在N1位选择性甲基化。或者,由10b反应短暂聚合N1官能化衍生物还开发了具有适当取代的仲胺的共聚物。因此,有利地利用这些合成策略来获得各种多样化衍生的3-取代的稠环[1