The elaboration of a 6,6-spiroacetal scaffold to incorporate a triazole unit as a peptide bond surrogate at the anomeric position is described. The novel spiroacetal-triazole hybrid structures were generated viacycloaddition of a spiroacetal azide to a series of alkynes. The spiroacetal framework was constructed viaBarbier reaction of bromide 10 with Weinreb amide 11, followed by acid-catalysed deprotection and cyclisation to afford the 6,6-spiroacetal ring system. The resultant ethoxy-spiroacetal 8 was converted to spiroacetal azide 5, which was then elaborated into a series of spiroacetal-triazole derivatives 7.
本文介绍了如何精心制作 6,6-螺
缩醛支架,以便在同分异构体位置加入三唑单元作为肽键替代物。新型螺
缩醛-三唑杂化结构是通过将螺
缩醛叠氮化物与一系列
炔烃进行紫外加载生成的。螺
缩醛框架是通过
溴化物 10 与 Weinreb 酰胺 11 的巴比尔反应构建的,然后在酸催化下进行脱保护和环化反应,得到 6,6 螺
缩醛环系统。由此得到的乙氧基螺
缩醛 8 被转化为螺
缩醛叠氮化物 5,然后又被制成一系列螺
缩醛三唑衍
生物 7。