申请人:Storer Richard
公开号:US20050059632A1
公开(公告)日:2005-03-17
An improved process for the preparation of 2′-modified nucleosides and 2′-deoxy-nucleosides, 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.
提供了一种改进的2'-改性核苷和2'-脱氧核苷的制备工艺,例如,β-L-2'-脱氧胸苷(LdT)。特别是,改进的工艺针对的是2'-脱氧核苷的合成,该合成可能使用不同的起始材料,但都通过氯糖中间体或通过2,2'-脱水-1-呋喃糖核苷中间体进行。当使用2,2'-脱水-1-呋喃糖碱基中间体时,会采用还原剂(如Red-Al)和隔离剂(如15-冠-5醚),它们能引起分子内位移反应,并形成所需核苷产品的高收率。本发明的一种替代工艺使用2,2'-脱水-1-呋喃糖碱基中间体而不使用隔离剂,也能以高收率获得2'-脱氧核苷。根据本发明制成的化合物可以作为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。