Cyclization reactions of 1-[3′-hydroxy-2′-(hydroxymethyl)prop-1′-enyl]pyrimidine nucleobases: intramolecular Michael additions to the C(5)C(6) bonds and intramolecular dehydrations
作者:Otto Dahl、Jacob Jensen、Michael Åxman Petersen、Ulla Henriksen
DOI:10.1039/b500777a
日期:——
nucleoside analogues 1a-f to undergo intramolecular cyclization reactions was investigated. All compounds, when treated with NaOD, were in equilibrium with the bicyclic compounds 2a-f, arising from Michael addition of a hydroxy group to the C(5)=C(6) bonds. Derivatives of 2,4-pyrimidinediones (1a,b) had the highest tendency to undergo intramolecular Michael addition when treated with triethylamine, whereas
研究了一系列无环核苷类似物1a-f进行分子内环化反应的趋势。当用NaOD处理时,所有化合物均与双环化合物2a-f处于平衡状态,这是由于在C(5)= C(6)键上加成了羟基而形成的。当用三乙胺处理时,2,4-嘧啶二酮(1a,b)的衍生物具有最高的分子内迈克尔加成趋势,而用酸对4-氨基-2-吡啶酮(1c-f)的环化进行得最好。的环外双键对于环化的发生至关重要。常用的N-保护基如苯甲酰基和二丁基氨基亚甲基可增强环化作用。在酸性无水条件下1b和1e环化为2,4'-无水化合物1b和1e。