申请人:Novartis AG
公开号:EP2157095A2
公开(公告)日:2010-02-24
An improved process for the preparation of 2'-modified nucleosides and 2'-deoxynucleosides, such as, β-L-2'-deoxy-thymidine (LdT), is provided. In particular, the improved process is directed to the synthesis of a 2'-deoxynucleoside that may utilize different starting materials but that proceeds via a chloro-sugar intermediate or via a 2,2' anhydro-1-furanosyl-nucleobase intermediate. Where an 2,2'-anhydro-1-furanosyl base intermediate is utilized, a reducing agent, such as Red-Al, and a sequestering agent, such as 15-crown-5 ether, that cause an intramolecular displacement reaction and formation of the desired nucleoside product in good yields are employed. An alternative process of the present invention utilizes a 2,2'-anhydro-1-furanosyl base intermediate without a sequestering agent to afford 2'-deoxynucleosides in good yields. The compounds made according to the present invention may be used as intermediates in the preparation of other nucleoside analogues, or may be used directly as antiviral and/or antineoplastic agents.
本发明提供了一种改进的方法,用于制备2'-修饰核苷和2'-去氧核苷,例如β-L-2'-去氧胸腺嘧啶(LdT)。特别是,改进的方法针对合成一种2'-去氧核苷,该方法可以利用不同的起始材料,但是通过氯代糖中间体或2,2'无水-1-呋喃基-核碱中间体进行。当使用2,2'-无水-1-呋喃基碱中间体时,采用还原剂(如Red-Al)和隔离剂(如15-冠-5醚),引起分子内位移反应并形成所需的核苷产物,产率良好。本发明的另一种替代方法利用无隔离剂的2,2'-无水-1-呋喃基碱中间体,以获得良好的2'-去氧核苷收率。根据本发明制备的化合物可以用作制备其他核苷类似物的中间体,或者可以直接用作抗病毒和/或抗肿瘤剂。