Stereocontrolled Synthesis of Triazacyclopenta[<i>cd</i>]pentalenes by Intramolecular 1,3-Dipolar Cycloaddition Reactions of Azomethine Imines
作者:Guillaume Bélanger、Fang-Tsao Hong、Larry E. Overman、Bruce N. Rogers、John E. Tellew、William C. Trenkle
DOI:10.1021/jo026282y
日期:2002.11.1
The construction of triazacyclopenta[cd]pentalene diesters 6 by the reaction of dihydropyrrole alpha-ketoesters 3 with acylated hydrazines was evaluated further as a potential central strategic step in the total syntheses of complex guanidine alkaloids such as palau'amine and styloguanidine. Successful cyclocondensations were realized with acid-stable 2,2,2-trichloroethyl carbazate and thiosemicarbazide
通过二氢吡咯α-酮酸酯3与酰化肼的反应构建三氮杂环戊[cd]戊二酯6,作为复杂胍生物碱如帕劳胺和苯乙烯基胍的总合成中的潜在中心战略步骤,进一步进行了评估。用酸稳定的2,2,2-三氯乙基氨基甲酸酯和硫代氨基脲进行成功的环缩合,而不是氨基甲酸叔丁酯。吡咯烷氮上的取代基可以是烷氧基羰基,磺酰基或N-烷基-2-酰基吡咯基。在α-酮酸酯侧链的C 1处的甲硅烷氧基取代也是可容忍的。