Three-Component Biginelli Cyclocondensation Reaction Using <i>C</i>-Glycosylated Substrates. Preparation of a Collection of Dihydropyrimidinone Glycoconjugates and the Synthesis of <i>C</i>-Glycosylated Monastrol Analogues
作者:Alessandro Dondoni、Alessandro Massi、Simona Sabbatini、Valerio Bertolasi
DOI:10.1021/jo0202076
日期:2002.10.1
aldehyde-ketoester-urea cyclocondensation reaction has been revisited using C-glycosylated reagents with the aim of exploring a potential entry to a library of dihydropyrimidinone glycoconjugates. A collection of 13 mono- and bis-C-glycosylated dihydropyrimidinones has been prepared by a parallel synthesis approach using the three-component promoter CuCl/AcOH/BF(3) x Et(2)O. The sugar residues have been
为了探索潜在进入二氢嘧啶酮糖缀合物文库的可能性,已经使用C-糖基化试剂重新研究了醛-酮酯-脲的环缩合反应。通过使用三组分促进剂CuCl / AcOH / BF(3)x Et(2)O的平行合成方法,已制备了13个单-和双-C-糖基化的二氢嘧啶酮的集合。糖残基已安装在单糖基化衍生物中的N1,C4或C6处,以及双糖基化产物中的C4和C6处。由于在二氢嘧啶酮环的C4立体中心的形成中糖残基的不对称诱导,因此获得了C4和C6处的单糖基和双糖基化产物,为非对映异构体的混合物,具有很好的选择性。单独的立体异构体被分离为纯净的化合物,其结构借助X射线晶体学和手性鉴定。作为Biginelli反应中这一新概念的证明,已经描述了在C6带有核糖呋喃糖基部分的两个C4差向异构体monastrol类似物的合成。