申请人:ZELIKOVITCH Lior
公开号:US20080262215A1
公开(公告)日:2008-10-23
Provided is a process for preparing gemcitabine or a salt thereof, which preferably includes selectively precipitating the β-anomer of a 3′,5′-di-O-protected-N
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-trimethylsilyl-2′-deoxy-2′,2′-difluorocytidine, removing the protecting groups to produce gemcitabine, and, optionally, converting the gemcitabine into a salt. Preferably, the 3′ and 5′ protecting groups are the same or different, and at least one of the 3′ and 5′ protecting groups is cinnamoyl, naphthoyl, naphthylmethylcarbonyl, 2-methylbenzylcarbonyl, 4-methylbenzylcarbonyl or 9-fluorenylmethyloxycarbonyl. Also provided are methods for enriching the β-anomer from an anomeric mixture of a 3′,5′-di-O-protected-N
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-trimethylsilyl-2′-deoxy-2′,2′-difluorocytidine, e.g., a N
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-trimethylsilyl-2′-deoxy-2′,2′-difluoro-cytidine-3′,5′-diester, e.g., 3′,5′-dicinnamoyl-N
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-trimethylsilyl-2′-deoxy-2′,2′-difluorocytidine, using a slurrying process, and methods for converting the β-anomer-enriched product into gemcitabine or a salt thereof.
提供了一种制备吉西他滨或其盐的过程,其优选包括选择性沉淀3′,5′-二保护-N4-三甲基硅基-2′-脱氧-2′,2′-二氟胞苷的β-异构体,去除保护基以产生吉西他滨,并可将吉西他滨转化为盐。优选地,3′和5′保护基相同或不同,并且3′和5′保护基中至少有一个是肉桂酰基,萘酰基,萘基甲基羰基,2-甲基苄基羰基,4-甲基苄基羰基或9-芴基甲氧羰基。还提供了一种使用搅拌法从3′,5′-二保护-N4-三甲基硅基-2′-脱氧-2′,2′-二氟胞苷的异构体混合物,例如N4-三甲基硅基-2′-脱氧-2′,2′-二氟胞苷-3′,5′-二酯,例如3′,5′-二肉桂酰基-N4-三甲基硅基-2′-脱氧-2′,2′-二氟胞苷,使用混悬过程富集β-异构体的方法,以及将富集β-异构体的产物转化为吉西他滨或其盐的方法。