| 摘要 |
<p>The invention relates to methods for producing gemcitabine derivatives of the general formula 6, or gemcitabine hydrochloride 7 (2'-desoxy-2',2'-difluorocytidine hydrochloride), to the silylated cytosine analogs 4c and 4d as intermediate products, and to the use thereof for reactions with 3,5-protected sugars of the general formula 5 into the corresponding protected 2'-desoxycytidines. The subsequent saponification of the protected cytidines removes not only the 3',5'-O-benzoate protecting groups, but also the N4-amidyl group, or the N4-guanidyl group, thereby obtaining the desired free cytidines 6. The subsequent treatment of gemcitabine derivatives of the general formula 6 with acids results in 2'-desoxy-2',2'-difluorocytidine hydrochloride (gemcitabine hydrochloride) 7.</p> |
