申请人:Naddaka Vladimir
公开号:US20070191598A1
公开(公告)日:2007-08-16
The present invention provides processes for preparing novel chemical substances that are useful as intermediates in the preparation of gemcitabine and processes for preparing gemcitabine therewith. Exemplary intermediates include mixtures of D-erythro and D-threo (3R- and 3S-) isomers of 3-(hydroxy)-2,2-difluoro-3-(2,2-dimethyldioxolan-4-yl)propionic acid salts. Also provided is a novel process for selectively isolating the D-erythro and D-threo isomers of the said salts in purities of at least about 95%, and processes of using them for preparing nucleoside analogs such as, e.g., gemcitabine and intermediates and analogs thereof.
本发明提供了用于制备新型化学物质的方法,这些化学物质可作为吉西他滨制备过程中的中间体,并提供了与之一起制备吉西他滨的方法。示例中间体包括3-(羟基)-2,2-二氟-3-(2,2-二甲基二氧杂环戊酮-4-基)丙酸盐的D-erythro和D-threo(3R-和3S-)异构体的混合物。还提供了一种新型方法,用于选择性地分离所述盐的D-erythro和D-threo异构体,其纯度至少约为95%,以及使用它们制备类似核苷类似物(例如吉西他滨及其中间体和类似物)的方法。