申请人:NADDAKA Vladimir
公开号:US20090221811A1
公开(公告)日:2009-09-03
The present invention provides processes for preparing intermediates useful in the preparation of gemcitabine and other nucleosides, and processes for preparing gemcitabine therewith. Exemplary intermediates include mixtures of D-erythro and D-threo isomers of 3-(hydroxy)-2,2-difluoro-3-(2,2-dimethyldioxolan-4-yl)-propionic acid salts. Also provided is a process for selectively isolating the D-erythro and D-threo isomers of D-erythro and D-threo isomers of 3-(hydroxy)-2,2-difluoro-3-(2,2-dimethyldioxolan-4-yl)-propionic acid salts, and processes for using such isomers in the preparation of nucleoside analogs such as, e.g., gemcitabine, intermediates thereof, and analogs thereof.
本发明提供了用于制备gemcitabine和其他核苷的中间体的制备过程,以及用该中间体制备gemcitabine的过程。示例中间体包括3-(羟基)-2,2-二氟-3-(2,2-二甲基二氧兰-4-基)-丙酸盐的D-erythro和D-threo异构体混合物。还提供了一种选择性分离D-erythro和D-threo异构体的D-erythro和D-threo异构体的3-(羟基)-2,2-二氟-3-(2,2-二甲基二氧兰-4-基)-丙酸盐的过程,并提供了使用这些异构体制备核苷类似物(例如gemcitabine,其中间体和类似物)的过程。