Stereoselectivity in the Synthesis of 3′-Deoxy-3′-C-(hydroxymethyl)uridines by Hydroboration and Conversion into a Building Block for Various 3′-Deoxy-3′-C-(methylene)uridine Analogues
作者:Anna Winqvist、Roger Strömberg
DOI:10.1002/1099-0690(200111)2001:22<4305::aid-ejoc4305>3.0.co;2-9
日期:2001.11
The stereoselectivity in hydroboration of 3′-deoxy-3′-C-(methylene)uridine derivatives has been studied. Hydroboration of 3′-deoxy-3′-C-(methylene)uridine derivatives gave two 3′-deoxy-3′-C-hydroxymethyl stereoisomers (with ribo or xylo configuration). The influence of reagent (BH3·Me2S, or 9-borabicyclo[3.3.1]nonane (9-BBN-H)) and solvent (THF, toluene, or hexane) was investigated. Use of BH3·Me2S
研究了3'-脱氧-3'- C-(亚甲基)尿苷衍生物在硼氢化反应中的立体选择性。3′-脱氧-3′- C-(亚甲基)尿苷衍生物的氢硼化得到两个3′-脱氧-3′- C-羟甲基立体异构体(具有核糖或木糖构型)。研究了试剂(BH 3 ·Me 2 S或9-硼环[3.3.1]壬烷(9-BBN-H))和溶剂(THF,甲苯或己烷)的影响。使用BH 3 ·Me 2 S得到木酮异构体作为主要产物。核糖的最高偏爱通过在己烷中使用9-BBN-H获得异构体。此外,当使用9-BBN-H作为试剂时,在5'-位置的羟基官能团的4-甲氧基三苯甲基保护导致比通过叔丁基二甲基甲硅烷基保护获得的更好的立体选择性。充其量,1- [2- O-(叔丁基二甲基甲硅烷基)-3-脱氧-3- C-亚甲基-5- O-(4-甲氧基三苯甲基)-β-D-赤型-戊呋喃糖基]尿嘧啶的硼氢化(3b)在己烷中使用9-BBN-H得到的核糖与木糖的异构体比率(4b