Ravikumar Vasulinga T, Kumar R Krishna, Capaldi Daniel C, Cole Douglas L
Isis Pharmaceuticals, Carlsbad, California 92009, USA.
Nucleosides Nucleotides Nucleic Acids. 2003 May-Aug;22(5-8):1421-5. doi: 10.1081/NCN-120023000.
Detritylation of a 5'-O-DMT-2'-deoxyadenosine moiety attached to solid support under acidic condition leads to depurination during oligonucleotide synthesis. Deprotection followed by reversed phase HPLC purification leads to desired oligonucleotide contaminated with significant levels of 3'-terminal phosphorothiaote (3'-TPT) monoester (n-1)-mer. However, it is demonstrated that attachment of dA nucleoside through its exocyclic amino group to solid support leads to substantial reduction of 3'-TPT formation thereby improving the quality of oligonucleotide synthesized.
在酸性条件下，连接在固相载体上的5'-O-DMT-2'-脱氧腺苷部分的去三苯甲基化反应会导致在寡核苷酸合成过程中发生脱嘌呤现象。脱保护后通过反相高效液相色谱法纯化，得到的目标寡核苷酸会被大量的3'-末端硫代磷酸酯（3'-TPT）单酯（n-1）-聚体污染。然而，已证明通过其环外氨基将dA核苷连接到固相载体上会导致3'-TPT形成量大幅减少，从而提高合成寡核苷酸的质量。
