1219934-68-5Relevant academic research and scientific papers
Glycosylation Enabled by Successive Rhodium(II) and Br?nsted Acid Catalysis
Meng, Lingkui,Wu, Peng,Fang, Jing,Xiao, Ying,Xiao, Xiong,Tu, Guangsheng,Ma, Xiang,Teng, Shuang,Zeng, Jing,Wan, Qian
, p. 11775 - 11780 (2019)
Herein, we reported on a highly efficient glycosylation reaction comprising two chronological meticulously designed catalytic cycles: (1) rhodium-catalyzed formation of sulfonium ylide and (2) Br?nsted acid-catalyzed formation of sulfonium ion. This protocol highlighted an effective and robust tactic to prepare a glycosyl sulfonium ion from a glycosyl sulfonium ylide precursor amenable for glycosylation.
Gold(I)-Catalyzed glycosylation with glycosyl ortho-alkynylbenzoates as donors: General scope and application in the synthesis of a cyclic triterpene saponin
Li, Yao,Yang, Xiaoyu,Liu, Yunpeng,Zhu, Cunsheng,Yang, You,Yu, Biao
scheme or table, p. 1871 - 1882 (2010/06/20)
Glycosyl ortho-alkynylbenzoates have emerged as a new generation of donors for glycosidation under the catalysis of gold(I) complexes such as Ph 3PAuOTf and Ph3PAuNTf2 (Tf= trifluoromethanesulfonate). A wide variety of these donors, including 2-deoxy sugar and sialyl donors, are easily prepared and shelf stable. The glycosidic coupling yields with alcohols are gener-ally excellent; even direct coupling with the poorly nucleophilic amides gives satisfactory yields. Moreover, excellent α-selective glycosylation with a 2-deoxy sugar donor and β-selective sialylation have been realized. Application of the present glycosylation protocol in the efficient synthesis of a cyclic triterpene tetrasaccharide have further demonstrated the versatility and efficacy of this new method, in that a novel chemoselective glycosylation of the carboxylic acid and a new one-pot sequential glycosylation sequence have been implemented.
