The present invention relates to a compound according to Formula (la) or (lb) wherein R1; R3; Y and X are defined herein, and their use in methods of nucleic acid synthesis. Disclosed herein is a method of reducing the deamination of the guanine base during oligonucleotide synthesis. The method is particularly applicable when nitrite is used to remove an aminooxy terminating moiety from the sugar hydroxyl.
吡咯并[2,3- d ]嘧啶的液-液相和固-液相转移糖基化:与2'-deoxy-7-carbaguanosine相关的2-deoxy-β-D-rifurfuranosides的立体定向合成
摘要:
2-氨基-4-甲氧基-7 H-吡咯并[2,3- d ]嘧啶(3b)与2-脱氧-3,5-二-O-(对甲苯甲酰基)-的相转移糖基化的产率α- d -赤-pentofuranosyl酰氯(4)液体-液体的条件下是有限的(50%NaOH水溶液,CH 2氯2,卜4 NHSO 4)由于碱-不稳定的保护基团在halogenose的脱保护(4) 。更具亲脂性的2-氨基-4-烷氧基吡咯并[2,3- d ]嘧啶的应用,例如化合物(3d)或(3e)在某种程度上减少了副反应。为了克服这些困难,已经开发了使用非质子传递溶剂,固体KOH和穴状三[2-(2-甲氧基乙氧基)乙基]胺(TDA-1)的固液相转移糖基化技术。新的糖基化方法以立体定向的方式高产地导致了2-amino-4-alkoxy-(7a–c)或2-amino-4-chloro-7 H -pyrrolo [2,3 - d ] pyrimidine2-deoxy-β-