A Remarkable Two-Step Synthesis of Diverse 1,4-Benzodiazepine-2,5-diones Using the Ugi Four-Component Condensation
作者:Thomas A. Keating、Robert W. Armstrong
DOI:10.1021/jo961517p
日期:1996.1.1
A two-step, general synthesis of 1,4-benzodiazepine-2,5-diones (BZDs) is presented. This synthesis employs an Ugi four-component condensation using a convertible isocyanide (1-isocyanocyclohexene), followed by an acid-activated cyclization reaction. This synthesis represents a dramatically improved route to BZDs over those currently in the literature. In addition, since amino acids are not used as
提出了两步的1,4-苯并二氮杂-2,5-二酮(BZDs)的一般合成。该合成采用可转化的异氰化物(1-异氰基环己烯)进行的Ugi四组分缩合,然后进行酸活化的环化反应。与目前文献中的那些相比,这种合成代表了向BZDs显着改善的途径。另外,由于不使用氨基酸作为输入,因此分子多样性的潜力远大于现有合成方法。还发现在室温下,在C-3和N-4位置被亚甲基取代的BZD在NMR光谱中显示构象异构现象。可变温度NMR实验支持这一观察结果,并得出有趣的结论,即在某些示例中,BZD核心结构可能不像以前想象的那样刚性。