A Simplified and Efficient Route to 2‘-<i>O</i>, 4‘-<i>C</i>-Methylene-Linked Bicyclic Ribonucleosides (Locked Nucleic Acid)
作者:Alexei A. Koshkin、Jef Fensholdt、Henrik M. Pfundheller、Christian Lomholt
DOI:10.1021/jo010732p
日期:2001.12.1
can be prepared from D-glucose in multigram scale. Four different nucleobases were stereoselectively coupled to 8 using a modified Vorbrüggen procedure to give the corresponding 4'-C-branched nucleoside derivatives. Subsequent ring closing furnished the protected LNA nucleosides. The 5'-O-mesyl groups were efficiently displaced by nucleophilic substitution using sodium benzoate. Saponification of the
描述了一种合成锁核酸(LNA)单体的新型有效方法。通过聚合合成制备了含有胸腺嘧啶,4-N-乙酰基和4-N-苯甲酰基胞嘧啶,6-N-苯甲酰腺嘌呤和2-N-异丁酰鸟嘌呤作为核碱基的LNA 5',3'-二醇。该方法基于使用常见的糖中间体1,2-二-O-乙酰基-3-O-苄基-4-C-甲磺酰氧基甲基-5-O-甲磺酰-D-赤型戊呋喃糖(8)可以从D-葡萄糖以克数制得。使用改良的Vorbrüggen程序将四个不同的核碱基立体选择性地偶联到8个核碱基上,得到相应的4'-C-支链核苷衍生物。随后的闭环提供了受保护的LNA核苷。使用苯甲酸钠通过亲核取代有效地置换了5'-O-甲磺酰基。将5'-苯甲酸酯皂化,然后催化除去3'-O-苄基,得到游离的LNA二醇。腺苷和胞苷的环外氨基被选择性地酰化,得到4-N-乙酰基或4-N-苯甲酰基-LNA-C和6-N-苯甲酰基-LNA-A。在制备2-N-异丁酰基-LNA-G期间,鸟