Stereochemistry of internucleotide bond formation by the H-phosphonate method. 7. Stereoselective formation of ribonucleoside (RP)- and (SP)-3′-H-phosphonothioate monoesters
作者:Michal Sobkowski、Jacek Stawinski、Adam Kraszewski
DOI:10.1016/j.tetasy.2010.01.022
日期:2010.3
Ribonucleoside 3′-H-phosphonothioate monoesters exist in the form of (RP)- and (SP)-diastereomers. In order to obtain them in good yields and in high stereochemical purity, stereoselective strategies for their preparation were investigated. For the synthesis of the (RP)-isomer, a stereoselective sulfhydrolysis of an activated nucleoside H-phosphonate was developed, while the monoesters with an (SP)-configuration
核糖核苷3'- H-硫代磷酸单酯以(R P)-和(S P)-非对映异构体形式存在。为了以高收率和高立体化学纯度获得它们,研究了其制备的立体选择策略。为了合成(R P)-异构体,开发了活化核苷H-膦酸酯的立体选择性硫水解,同时通过不对称转化核苷3'- H的非对映异构体混合物制备了具有(S P)-构型的单酯。-硫代磷酸酯,可使用与9-芴甲醇的缩合反应,然后进行β-消除,或通过Pivaloylation-hydrolysis反应顺序进行。通过立体化学相关分析,初步确定了所获得的3'- H-硫代磷酸膦酸酯的非对映异构体的绝对构型。