de Rooij J F, Wille-Hazeleger G, Burgers P M, van Boom J H
Nucleic Acids Res. 1979;6(6):2237-59. doi: 10.1093/nar/6.6.2237.
Two examples of neighbouring group participation during the removal of protecting groups from phosphotriesters of partially or fully protected intermediates of nucleic acids are presented. The first example shows that ammonolysis of aryl groups from phosphotriesters of partially protected - 5'- hydroxy free - nucleic acids (e.g., 4b approximately to; Ar=2C1C 6H4) gives rise to the formation of unnatural nucleic acids (e.g., 7 approximately to and 8 approximately to). The second one illustrates that fluoride ion promoted hydrolysis of 2,2,2-trichloroethyl groups from phosphotriesters of fully protected nucleic acids (e.g., 18a approximately to), having t-butyldimethylsilyl groups at the 2'-positions, leads to the formation of a considerable amount of side-products (e.g., 20 approximately to and 21 approximately to).
本文给出了两个关于从核酸部分或完全保护中间体的磷酸三酯上去除保护基团过程中邻基参与的例子。第一个例子表明,从部分保护的 - 5'-羟基游离 - 核酸的磷酸三酯(例如,4b 约至;Ar = 2C1C 6H4)上氨解芳基会导致形成非天然核酸(例如,7 约至和 8 约至)。第二个例子说明,在2'-位带有叔丁基二甲基甲硅烷基的完全保护核酸的磷酸三酯(例如,18a 约至)上,氟离子促进的2,2,2 - 三氯乙基基团的水解会导致形成大量副产物(例如,20 约至和 21 约至)。