<i>N</i>-Oxides of Adenosine-Type Nucleosides Undergo Pyrimidine Ring Opening and Closure To Give 5-Amino-4-(1,2,4-oxadiazol-3-yl)imidazole Derivatives
作者:Ireneusz Nowak、John F. Cannon、Morris J. Robins
DOI:10.1021/ol061715v
日期:2006.9.1
Treatment of acylated adenosine N-oxides with carboxylic anhydrides and thiophenol resulted in pyrimidine ring opening followed by exocyclic ring closure. Ammonolysis gave 5-amino-4-(5-substituted-1,2,4-oxadiazol-3-yl)-1-(beta-d-ribofuranosyl)imidazole derivatives, whereas iodine in methanol selectively unmasked the 5-amino group. Related flexible nucleoside analogues can be prepared from adenine-type
用羧酸酐和苯硫酚处理酰化的腺苷N-氧化物导致嘧啶开环,然后闭环。氨解产生5-氨基-4-(5-取代的1,2,4-恶二唑-3-基)-1-(β-d-呋喃呋喃糖基)咪唑衍生物,而甲醇中的碘选择性地掩盖了5-氨基。相关的柔性核苷类似物可以从腺嘌呤型前体制备。