51820-70-3Relevant articles and documents
Stereoselective N-glycosylation with N4-acyl cytosines and efficient synthesis of gemcitabine
Liu, Tongchao,Tang, Jiadeng,Liang, Jianpeng,Chen, Yabin,Wang, Xiaowen,Shen, Jingkang,Zhao, Dongmei,Xiong, Bing,Cen, Jun-Da,Chen, Yue-Lei
, p. 1203 - 1213 (2019)
Through systematical comparison of various N4-protected cytosine derivatives in the glycosylation step of gemcitabine synthesis, highly beta-stereoselective and high yielding TBAI catalyzed N-glycosylation was achieved with N4-Bz cytosine and anomeric mixture of 2,2‘-difluororibose mesylate donor. The subsequent global deprotection gave gemcitabine efficiently. Meanwhile, the anomeric chloride intermediate and fluoride-displaced side products of this N-glycosylation were identified, too. This new glycosylation method reveals the importance of N4-protection in the stereoselective preparation of pyrimidine nucleoside, also provides a potential alternative to current industrial process to gemcitabine.
A direct synthesis of nucleoside analogs homologated at the 3′- and 5′-positions
Schmidt, Juergen,Eschgfaeller, Bernd,Benner, Steven A.
, p. 2937 - 2958 (2007/10/03)
A new route is presented to prepare analogs of nucleosides homologated at the 3′- and 5′-positions. This route, applicable to both the D- and L-enantiomeric forms, is suitable for the preparation of monomeric bis-homonucleosides needed for the synthesis o
